CN204424903U - A kind of Coal Mining Power Distribution System dynamic analog circuit - Google Patents

Abstract

The utility model discloses a kind of Coal Mining Power Distribution System dynamic analog circuit, comprise high-voltage power supply circuit and low voltage feeder circuit, and for the magnetic powder brake of fictitious load and the fault simulation circuit that is connected with high-voltage power supply circuit or low voltage feeder circuit; High-voltage power supply circuit is connected with 380V civil power transmission line, the low voltage feeder branch road that low voltage feeder circuit comprises reduction voltage circuit and is connected with reduction voltage circuit, and the harmonic source to be all connected with reduction voltage circuit and low voltage feeder branch road, magnetic powder brake is connected with low voltage feeder branch road; High-voltage power supply circuit comprises step-up transformer T1, high voltage supply circuit and zero-sequence reactor ARC, and reduction voltage circuit is made up of step-down transformer T2, and fault simulation circuit comprises gradually changeable leakage analog circuit and short circuit analog circuit.The utility model has flexibly, dynamic modeling ability, the authenticity of dynamic analog result and practical, and result of use is good.

Description

A dynamic analog circuit for coal mine power supply and distribution system

technical field

The utility model belongs to the technical field of power supply and distribution safety in coal mines, in particular to a dynamic analog circuit for power supply and distribution systems in coal mines.

Background technique

Underground coal mine is a typical explosive environment, and its power supply system generally adopts the operation mode of non-effective neutral point grounding. Due to the harsh electricity environment of the mine, the power supply lines and equipment of the working face are prone to leakage, grounding, short-circuit and other faults. The high temperature and electric sparks caused by the faults are the main fire sources leading to explosion accidents. Once an explosion occurs, it will directly threaten the entire The life safety of underground workers, and cause bad social impact and major economic losses, so coal mine production has high requirements for the safety and reliability of power supply. Various protection systems used in the mine often refuse to operate and malfunction. It is imminent to develop new principles and new technologies for mine relay protection. The research and development of new principles and new technologies must rely on a powerful test platform. A new mine power supply equipment must also be tested before being put into use.

Due to the large difference in operating characteristics between the mine power supply system and the ground power supply system, there is currently no dynamic simulation system that can effectively address the uniqueness of mine power supply. There are mainly two methods for the existing simulation system. One is to use various commercial simulation software to build a numerical model of the mine power supply system on the computer, and to complete the simulation and experiment by solving differential equations. This simulation environment is completely ideal. It is simple to build under the ground, but it is very different from the actual operating conditions of the underground power supply system. Many faults with gradual changes and the dynamic physical characteristics of the equipment cannot be simulated. The simulation results can only be used as a preliminary understanding of the mine power supply system. refer to. The second simulation system uses 380V as the experimental voltage. The experimental system does not include transformers, transformers, loads and other actual equipment. Although the simulation results are better than computer simulations, they are still far from the actual situation. Mine mainly adopts 10kV and 3300V power supply voltages, and the length of insulation life is mainly related to the voltage level. The difference in voltage level has a great influence on the insulation performance of equipment, especially cables, which directly leads to the research on the occurrence and evolution of leakage faults. big error. For the inspection and testing of relay protection devices, it is necessary to comprehensively consider the dynamic operating conditions of the system, the saturation characteristics of transformers and transformers, and the comprehensive impact of load changes on electrical equipment, which cannot be realized in the 380V experimental system.

Due to the lack of a real mine dynamic simulation system, the inspection of the performance of mine equipment ultimately depends on the actual application in the mine, and the research and understanding of the operation law of the mine power supply system and the mechanism of various failures can only be done through simulation software or on the ground. The low-voltage experimental system is simulated, so mine power supply equipment failures occur frequently, the reliability of the protection system is not high, and it is inevitable that the safety of coal mine power supply cannot be effectively guaranteed. The basic theoretical research on power supply safety in explosive environments is always in a relatively weak state.

Utility model content

The technical problem to be solved by the utility model is to provide a dynamic analog circuit for the coal mine power supply and distribution system in view of the deficiencies in the above-mentioned prior art. The modeling ability, the authenticity and practicability of the dynamic simulation results are strong, the use effect is good, and it is easy to promote and use.

In order to solve the above technical problems, the technical solution adopted by the utility model is: a dynamic analog circuit for power supply and distribution system in coal mine, which is characterized in that it includes a high-voltage power supply circuit for converting 380V voltage into 10kV voltage and outputting power supply and for Convert the 10kV voltage output by the high-voltage power supply circuit into 3300V voltage and output the low-voltage feeder circuit for power supply, as well as the magnetic powder brake used to simulate the load and the fault simulation circuit connected to the high-voltage power supply circuit or the low-voltage feeder circuit; the high-voltage power supply circuit Connected with the 380V mains transmission line, the low-voltage feeder circuit includes a step-down circuit for converting 10kV voltage to 3300V voltage and a low-voltage feeder branch connected to the step-down circuit, as well as a link with the step-down circuit and low-voltage feeder A harmonic source connected to both branches, and the magnetic powder brake is connected to a low-voltage feeder branch;

The high-voltage power supply circuit includes a step-up transformer T1 for converting 380V voltage to 10kV voltage, a high-voltage power supply line and a zero-sequence reactor ARC. The step-up transformer T1 is a three-phase double-winding transformer, and the step-up transformer T1 The primary side winding of the step-up transformer T1 is a delta connection, the secondary side winding of the step-up transformer T1 is a star connection, and the primary side winding of the step-up transformer T1 is connected to the 380V mains transmission line through a three-phase switch K1, so One end of the zero-sequence reactor ARC is connected to the neutral point of the secondary side winding of the step-up transformer T1 through a single-phase switch K2. The first end of the A-phase high-voltage power supply line is terminal a and is connected to the first terminal of the secondary side winding of the step-up transformer T1, and the first end of the B-phase high-voltage power supply line is terminal b And connected to the second terminal of the secondary side winding of the step-up transformer T1, the first end of the C-phase high-voltage power supply line is terminal c and connected to the third terminal of the secondary side winding of the step-up transformer T1;

The step-down circuit is composed of a step-down transformer T2, the step-down transformer T2 is a three-phase double-winding transformer, the primary side winding of the step-down transformer T2 is a delta connection, and the secondary side of the step-down transformer T2 The winding is star-connected, and the number of the low-voltage feeding branches is three, which are respectively the first low-voltage feeding branch, the second low-voltage feeding branch and the third low-voltage feeding branch, and the step-down transformer The three terminals of the primary side winding of T2 are respectively connected to the end of the A-phase high-voltage power supply line, the end of the B-phase high-voltage power supply line and the end of the C-phase high-voltage power supply line, and the A-phase high-voltage power supply line The end of the terminal, the end of the B-phase high-voltage power supply line and the end of the C-phase high-voltage power supply line are terminal d, terminal e and terminal f respectively, and the harmonic source passes through three-phase switches K7 and The three-phase switch K3 is connected to the three terminals of the secondary side winding of the step-down transformer T2, and the first low-voltage feeding branch is connected to the three-phase switch K7 and the three-phase switch K3 through the three-phase switch K4 The second low-voltage feeder branch is connected to the connection line connecting the three-phase switch K7 and the three-phase switch K3 through the three-phase switch K5, and the third low-voltage feeder branch is connected to the three-phase switch K6 through the three-phase switch K6. The phase switch K7 is connected to the connection line of the three-phase switch K3, the three-phase input ends of the first low-voltage feeder branch are respectively connection terminal g, connection terminal h and connection terminal i, and the second low-voltage feeder branch The three-phase input ends of the three-phase input terminal are respectively connection terminal j, connection terminal k and connection terminal l, the three-phase input ends of the third low-voltage feeder branch are respectively connection terminal m, connection terminal n and connection terminal o, and the first The three-phase output ends of a low-voltage feeder branch are respectively connection terminal p, connection terminal q and connection terminal r, and the three-phase output ends of the second low-voltage feeder branch are respectively connection terminal s, connection terminal t and connection terminal Terminal u, the three-phase output terminals of the third low-voltage feeder branch are terminal v, terminal w and terminal x respectively;

The fault simulation circuit includes a gradual leakage simulation circuit and a short circuit simulation circuit, the gradual leakage simulation circuit is composed of a single-phase switch K9 and a sliding rheostat R16, the sliding end of the sliding rheostat R16 is grounded, and the sliding rheostat R16 One fixed end is connected with one end of the single-phase switch K9, and the other end of the single-phase switch K9 is the output terminal OUT1 of the gradual leakage analog circuit; the short-circuit analog circuit is composed of a sliding rheostat R17, a single-phase switch K10, a single-phase switch K11, single-phase switch K12, single-phase switch K13 and single-phase switch K14, one fixed end of the sliding rheostat R17 passes through single-phase switch K14 and one end of single-phase switch K10, one end of single-phase switch K11, single-phase switch One end of K12 is connected to one end of the single-phase switch K13, the sliding end of the sliding rheostat R17 and the other end of the single-phase switch K13 are both grounded, and the other end of the single-phase switch K10 is the first output terminal OUT2 of the short-circuit analog circuit , the other end of the single-phase switch K11 is the second output end OUT3 of the short-circuit analog circuit, and the other end of the single-phase switch K12 is the third output end OUT4 of the short-circuit analog circuit; the output of the gradual leakage analog circuit Terminal OUT1 is connected with terminals a~c or any one of them, any two terminals, or with terminals d~f or any one of them, any two terminals, or with terminals g~i or any one of them, any Two connection terminals, or connection terminals j~l or any one of them, any two connection terminals, or connection terminals m~o or any one of them, any two connection terminals, or connection terminals p~r or any of them Any one, any two terminals, or connected with terminals s~u, or any one, any two terminals, or connected with terminals v~x, or any one, any two terminals; the short circuit simulation Any one of the first output terminal OUT2 of the circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit is connected to any one of the connection terminals a~x, or the Any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit and any two connection terminals of the connection terminals a~c, Or with any two of terminals d~f, or with any two of terminals g~i, or with any two of terminals j~l, or with terminal m Any two terminals in ~o, or any two terminals in p~r, or any two terminals in s~u, or any two terminals in v~x The two connection terminals are connected, or the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit and the third output terminal OUT4 of the short-circuit analog circuit are respectively connected to the connection terminals a～c, or connected to the connection terminals a~c respectively. Terminal d～f, Or with terminals g~i, or with terminals j~l, or with terminals m~o, or with terminals p~r, or with terminals s~u, or with terminals v~x connection.

The dynamic analog circuit of the above-mentioned coal mine power supply and distribution system is characterized in that: a single-phase current transformer CT1 is connected to the connection line between the single-phase switch K2 and the secondary side winding of the step-up transformer T1, and the high-voltage power supply A voltage transformer PT1 is connected to the connection line between the line and the secondary side winding of the step-up transformer T1; a voltage transformer PT1 is connected to the connection line between the three-phase switch K3 and the three terminals of the secondary side winding of the step-down transformer T2. The voltage transformer PT2, the connection line connected between the three-phase switch K4 and the connection line connecting the three-phase switch K7 and the three-phase switch K3 is connected with a zero-sequence current transformer CT2, a single-phase current transformer CT5, a single-phase current transformer CT6 and single-phase current transformer CT7, the connecting line connected between the three-phase switch K5 and the connection line connecting three-phase switch K7 and three-phase switch K3 is connected with zero-sequence current transformer CT3, single-phase current transformer CT8 , single-phase current transformer CT9 and single-phase current transformer CT10, the connecting line that described three-phase switch K6 is connected with the connection line that connects three-phase switch K7 and three-phase switch K3 is connected with zero-sequence current transformer CT4, single-phase current transformer Phase current transformer CT11, single-phase current transformer CT12 and single-phase current transformer CT13.

The dynamic analog circuit of the above-mentioned coal mine power supply and distribution system is characterized in that: the A-phase high-voltage power supply line is composed of a resistor R1, a capacitor C1 and an inductor L1, and one end of the inductor L1 is connected to one end of the capacitor C1 and is A The first end of the phase high-voltage power supply line, one end of the resistor R1 is connected to one end of the inductor L1 and is the end of the A-phase high-voltage power supply line, the other end of the capacitor C1 and the other end of the resistor R1 are both grounded; the B-phase The high-voltage power supply line is composed of a resistor R2, a capacitor C2, and an inductor L2. One end of the inductor L2 is connected to one end of the capacitor C2 and is the first end of the B-phase high-voltage power supply line. One end of the resistor R2 is connected to one end of the inductor L2. It is the end of the B-phase high-voltage power supply line, and the other end of the capacitor C2 and the other end of the resistor R2 are both grounded; the C-phase high-voltage power supply line is composed of a resistor R3, a capacitor C3 and an inductor L3, and one end of the inductor L3 is connected to the One end of the capacitor C3 is connected to the first end of the C-phase high-voltage power supply line, one end of the resistor R3 is connected to one end of the inductor L3 and is the end of the C-phase high-voltage power supply line, and the other end of the capacitor C3 is connected to the other end of the resistor R3. Both ends are grounded.

The above-mentioned dynamic analog circuit of a coal mine power supply and distribution system is characterized in that: the first low-voltage feeder branch is composed of the first U-phase low-voltage feeder branch, the first V-phase low-voltage feeder branch and the first W-phase The first U-phase low-voltage feed branch is composed of a resistor R4, a capacitor C4, and an inductor L4. One end of the inductor L4 is connected to one end of the capacitor C4 and is the first U-phase low-voltage feed branch. The first end of the circuit, one end of the resistor R4 is connected to one end of the inductor L4 and is the end of the first U-phase low-voltage feeder branch, the other end of the capacitor C4 and the other end of the resistor R4 are both grounded, and the first A V-phase low-voltage feed branch is composed of a resistor R5, a capacitor C5, and an inductor L5. One end of the inductor L5 is connected to one end of the capacitor C5 and is the first end of the first V-phase low-voltage feed branch. The resistor R5 One end is connected to one end of the inductor L5 and is the end of the first V-phase low-voltage feeding branch, the other end of the capacitor C5 and the other end of the resistor R5 are both grounded, and the first W-phase low-voltage feeding branch is connected by a resistor R6 , a capacitor C6 and an inductor L6, one end of the inductor L6 is connected to one end of the capacitor C6 and is the first end of the first W-phase low-voltage feed branch, and one end of the resistor R6 is connected to one end of the inductor L6 and is the first end of the first W-phase low-voltage feed branch. The end of a W-phase low-voltage feed branch, the other end of the capacitor C6 and the other end of the resistor R6 are grounded; the second low-voltage feed branch is composed of the second U-phase low-voltage feed branch, the second V-phase The low-voltage feeding branch is composed of a second W-phase low-voltage feeding branch, the second U-phase low-voltage feeding branch is composed of a resistor R7, a capacitor C7 and an inductor L7, and one end of the inductor L7 is connected to one end of the capacitor C7 And it is the first end of the second U-phase low-voltage feeding branch, one end of the resistor R7 is connected to one end of the inductor L7 and is the end of the second U-phase low-voltage feeding branch, the other end of the capacitor C7 and the resistor The other ends of R7 are both grounded, and the second V-phase low-voltage feed branch is composed of a resistor R8, a capacitor C8 and an inductor L8, and one end of the inductor L8 is connected to one end of the capacitor C8 and is the second V-phase low-voltage feed branch The first end of the circuit, one end of the resistor R8 is connected to one end of the inductor L8 and is the end of the second V-phase low-voltage feed branch, the other end of the capacitor C8 and the other end of the resistor R8 are grounded, and the first The two W-phase low-voltage feeder branches are composed of a resistor R9, a capacitor C9 and an inductor L9, one end of the inductor L9 is connected to one end of the capacitor C9 and is the first end of the second W-phase low-voltage feeder branch, and the resistor R9 One end is connected to one end of the inductor L9 and is the end of the second W-phase low-voltage feed branch, the other end of the capacitor C9 and the other end of the resistor R9 are both grounded; the third low-voltage feed branch is connected by the third U-phase A low-voltage feed branch, a third V-phase low-voltage feed branch and a third W-phase low-voltage feed branch, the third U-phase low-voltage feed branch is composed of a resistor R10, a capacitor C10 and an inductor L10, the One end of the inductor L10 is connected to one end of the capacitor C10 and is the first end of the third U-phase low-voltage feeding branch, and one end of the resistor R10 is connected to one end of the inductor L10 and is the third U-phase low-voltage feeding branch. At the end of the feeding branch, the other end of the capacitor C10 and the other end of the resistor R10 are both grounded, and the third V-phase low-voltage feeding branch is composed of a resistor R11, a capacitor C11 and an inductor L11, and one end of the inductor L11 It is connected to one end of the capacitor C11 and is the first end of the third V-phase low-voltage feed branch, and one end of the resistor R11 is connected to one end of the inductor L11 and is the end of the third V-phase low-voltage feed branch. The other end of C11 and the other end of resistor R11 are both grounded, and the third W-phase low-voltage feed branch is composed of resistor R12, capacitor C12 and inductor L12, one end of the inductor L12 is connected to one end of capacitor C12 and is the third The first end of the W-phase low-voltage feed branch, one end of the resistor R12 is connected to one end of the inductor L12 and is the end of the third W-phase low-voltage feed branch, the other end of the capacitor C12 and the other end of the resistor R12 Both are grounded.

The above-mentioned dynamic analog circuit for a coal mine power supply and distribution system is characterized in that: the maximum resistance of the sliding rheostat R16 is 5000Ω, and the maximum resistance of the sliding rheostat R17 is 500Ω.

Compared with the prior art, the utility model has the following advantages:

1. The utility model adopts the same power supply voltage level and main wiring as the coal mine power supply and distribution system, and considers the dynamic influence of actual transformers, line parameters, transformers, and load changes on the system, and can truly reproduce the actual coal mine to the greatest extent. The power supply and distribution system can provide a wealth of data reflecting the operating characteristics of the system and the nature of faults, and the authenticity and practicability of the dynamic simulation results are strong.

2. The utility model is flexible in construction and novel in design. According to different requirements of research and testing, different operation modes of coal mine power supply and distribution systems can be simulated through flexible changes of switch states, and gradual changes can be dynamically simulated through continuous changes in the resistance of sliding rheostats. The occurrence process of permanent leakage faults; through multiple switch combinations and state changes, various single faults and combined faults of the coal mine power supply and distribution system can be dynamically simulated.

3. The utility model is equipped with a main transmission line and a multi-branch low-voltage feeder line, and is equipped with a power supply main switch and a branch switch. The parameters of different branch low-voltage feeder lines are set to different values, which can dynamically simulate feeder lines of different lengths, and can The vertical selection performance, horizontal selection performance and sensitivity performance of the leakage protection of mine comprehensive protector, the vertical selection performance, horizontal selection performance, sensitivity performance and reliability performance of mine comprehensive protector short circuit protection, and the mine comprehensive protector The longitudinal selection performance and lateral selection performance of single-phase grounding protection are dynamically simulated and tested under various conditions.

4. The utility model can simulate the power quality pollution of the power supply system caused by electric locomotives, frequency conversion speed control equipment, and traction equipment in the coal mine power supply and distribution system, and is used for dynamic analysis of the coal mine power supply and distribution system under severe power supply quality pollution conditions. Simulation can be used to study the harmonic control technology of mines.

5. The utility model system is flexible in construction, can be used for comprehensive detection of mine electrical equipment performance, can provide abundant fault data, is a good test platform for researching power supply safety, and is the basis for developing new technologies for mine relay protection and basis.

In summary, the operating voltage of the utility model is completely consistent with the actual situation of the coal mine power supply and distribution system. It has flexible and dynamic modeling capabilities, the authenticity and practicability of the dynamic simulation results are strong, the use effect is good, and it is easy to popularize and use. .

The technical solutions of the present utility model will be further described in detail through the drawings and embodiments below.

Description of drawings

Fig. 1 is the block diagram of circuit principle of the utility model.

Fig. 2 is the circuit schematic diagram of the gradient leakage analog circuit of the utility model.

Fig. 3 is the circuit schematic diagram of the short-circuit analog circuit of the utility model.

Fig. 4 is a schematic diagram of the circuit connection of the 380V mains power transmission line, the high-voltage power supply circuit and the low-voltage feed circuit of the utility model.

Explanation of reference signs:

1—High voltage power supply circuit; 2—Low voltage feed circuit; 2-1—Decompression circuit;

2-2—Low-voltage feeder branch; 2-3—Harmonic source; 3—Magnetic powder brake;

4—fault simulation circuit; 5—380V mains transmission line.

Detailed ways

As shown in Figure 1, a dynamic analog circuit of a coal mine power supply and distribution system of the present utility model includes a high-voltage power supply circuit 1 for outputting power after converting 380V voltage into 10kV voltage and a 10kV power supply circuit for outputting high-voltage power supply circuit 1 After the voltage is converted to 3300V, the low-voltage feeder circuit 2 for power supply is output, and the magnetic powder brake 3 for simulating the load and the fault simulation circuit 4 connected with the high-voltage power supply circuit 1 or the low-voltage feeder circuit 2; the high-voltage power supply circuit 1 and 380V mains power transmission line 5 is connected, and the low-voltage feeder circuit 2 includes a step-down circuit 2-1 for converting 10kV voltage to 3300V voltage and a low-voltage feeder branch 2-2 connected with the step-down circuit 2-1 , and a harmonic source 2-3 connected to both the step-down circuit 2-1 and the low-voltage feed branch 2-2, and the magnetic powder brake 3 is connected to the low-voltage feed branch 2-2;

As shown in Figure 4, the high-voltage power supply circuit 1 includes a step-up transformer T1 for converting 380V voltage to 10kV voltage, a high-voltage power supply line and a zero-sequence reactor ARC, and the step-up transformer T1 is a three-phase double-winding transformer , the primary side winding of the step-up transformer T1 is a delta connection, the secondary side winding of the step-up transformer T1 is a star connection, and the primary side winding of the step-up transformer T1 is connected to 380V through a three-phase switch K1 Mains power transmission line 5 is connected, one end of the zero-sequence reactor ARC is connected to the neutral point of the secondary side winding of the step-up transformer T1 through a single-phase switch K2, and the high-voltage power supply line is composed of A-phase high-voltage power supply line, B-phase phase high-voltage power supply line and C-phase high-voltage power supply line. The first end of the line is the terminal b and is connected to the second terminal of the secondary side winding of the step-up transformer T1, and the first end of the C-phase high-voltage power supply line is the terminal c and is connected to the secondary side The third terminal of the winding is connected; the secondary side winding of the step-up transformer T1 adopts a star connection method, and there is no need to add a grounding transformer like the real coal mine power supply and distribution system, so that the secondary side winding of the step-up transformer T1 can The neutral point of the winding is connected to the zero-sequence reactor ARC to simulate the neutral point compensation grounding operation mode and the neutral point insulation operation mode; and the primary side winding of the step-up transformer T1 adopts a delta connection method, which interrupts the third harmonic current loop , avoiding the impact of the third harmonic current on the 380V mains transmission line 5 on the entire coal mine power supply and distribution system;

As shown in Figure 4, the step-down circuit 2-1 is composed of a step-down transformer T2, the step-down transformer T2 is a three-phase double-winding transformer, and the primary side winding of the step-down transformer T2 is a delta connection, so The secondary side winding of the step-down transformer T2 is star-connected, and the number of the low-voltage feeding branches 2-2 is three, which are respectively the first low-voltage feeding branch, the second low-voltage feeding branch and the second low-voltage feeding branch. Three low-voltage feeding branches, the three terminals of the primary side winding of the step-down transformer T2 are respectively connected to the end of the A-phase high-voltage power supply line, the end of the B-phase high-voltage power supply line and the C-phase high-voltage power supply The ends of the lines are connected, the ends of the A-phase high-voltage power supply line, the B-phase high-voltage power supply line and the C-phase high-voltage power supply line are terminal d, terminal e and terminal f respectively. The harmonic source 2-3 is connected to the three terminals of the secondary side winding of the step-down transformer T2 through the three-phase switch K7 and the three-phase switch K3 connected in series in sequence, and the first low-voltage feeding branch is connected through the three-phase The switch K4 is connected to the connection line connecting the three-phase switch K7 and the three-phase switch K3, and the second low-voltage feeder branch is connected to the connection line connecting the three-phase switch K7 and the three-phase switch K3 through the three-phase switch K5, and the The third low-voltage feeder branch is connected to the connection line connecting the three-phase switch K7 and the three-phase switch K3 through the three-phase switch K6, and the three-phase input ends of the first low-voltage feeder branch are respectively terminal g, terminal h and connection terminal i, the three-phase input terminals of the second low-voltage feed branch are connection terminal j, connection terminal k and connection terminal l respectively, and the three-phase input terminals of the third low-voltage feed branch are respectively Connecting terminal m, connecting terminal n and connecting terminal o, the three-phase output ends of the first low-voltage feeder branch are respectively connecting terminal p, connecting terminal q and connecting terminal r, the second low-voltage feeding branch The three-phase output terminals are terminal s, terminal t and terminal u respectively, and the three-phase output terminals of the third low-voltage feeder branch are terminal v, terminal w and terminal x respectively; step-down transformer T2 The secondary side winding of the secondary winding adopts a delta connection method, which interrupts the third harmonic current loop and avoids the influence of the third harmonic current on the low-voltage feeder branch 2-2 on the high-voltage power supply line;

The fault simulation circuit 4 includes a gradual leakage simulation circuit and a short circuit simulation circuit, as shown in Figure 2, the gradual leakage simulation circuit is composed of a single-phase switch K9 and a sliding rheostat R16, the sliding end of the sliding rheostat R16 is grounded , a fixed end of the sliding rheostat R16 is connected to one end of the single-phase switch K9, and the other end of the single-phase switch K9 is the output terminal OUT1 of the gradual leakage analog circuit; as shown in Figure 3, the short-circuit analog circuit It is composed of sliding rheostat R17, single-phase switch K10, single-phase switch K11, single-phase switch K12, single-phase switch K13 and single-phase switch K14. One fixed end of the sliding rheostat R17 connects with single-phase switch K10 through single-phase switch K14 One end of the single-phase switch K11, one end of the single-phase switch K12 and one end of the single-phase switch K13 are connected, the sliding end of the sliding rheostat R17 and the other end of the single-phase switch K13 are grounded, and the single-phase switch K10 The other end of the single-phase switch K11 is the first output end OUT2 of the short-circuit analog circuit, the other end of the single-phase switch K11 is the second output end OUT3 of the short-circuit analog circuit, and the other end of the single-phase switch K12 is the third output end of the short-circuit analog circuit. Output terminal OUT4; the output terminal OUT1 of the gradual leakage analog circuit is connected with terminals a~c or any one of them, any two terminals, or with terminals d~f or any one of them, any two terminals, Or with terminals g~i or any one of them, any two terminals, or with terminals j~l or any one of them, any two terminals, or with terminals m~o or any one of them, any two terminals a terminal, or with terminals p~r or any one of them, any two terminals, or with terminals s~u or any one of them, any two terminals, or with terminals v~x or any of them One, any two terminals are connected; any one of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit and the third output terminal OUT4 of the short-circuit analog circuit is connected to the terminal a Any one of the connection terminals in ~x is connected, or any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit are connected to Any two of the terminals a to c, or any two of the terminals d to f, or any two of the terminals g to i, or any two of the terminals j to l Any two terminals in, or with any two terminals in terminals m~o, or with any two terminals in terminals p~r, or with any two terminals in s~u Connecting terminals, or connecting any two connecting terminals in the connecting terminals v～x, or the first output end OUT2 of the short-circuit analog circuit, the second output end OUT3 of the short-circuit analog circuit and the third output end of the short-circuit analog circuit OUT4 is respectively connected to terminals a~c , respectively with terminals d~f, or with terminals g~i, or with terminals j~l, or with terminals m~o, or with terminals p~r, or with terminals Terminals s~u, or connected to terminals v~x respectively. During specific implementation, the other fixed end of the sliding rheostat R16 and the other fixed end of the sliding rheostat R17 are suspended.

As shown in Figure 4, in this embodiment, a single-phase current transformer CT1 is connected to the connection line between the single-phase switch K2 and the secondary side winding of the step-up transformer T1, and the high-voltage power supply line and the step-up transformer T1 A voltage transformer PT1 is connected to the connection line of the secondary side winding of the step-down transformer T2; a voltage transformer PT2 is connected to the connection line of the three-phase switch K3 and the three terminals of the secondary side winding of the step-down transformer T2, so The connecting line connecting the three-phase switch K4 and the connecting line connecting the three-phase switch K7 and the three-phase switch K3 is connected with a zero-sequence current transformer CT2, a single-phase current transformer CT5, a single-phase current transformer CT6 and a single-phase current transformer. Transformer CT7, the connecting line connecting the three-phase switch K5 and the connecting line connecting the three-phase switch K7 and the three-phase switch K3 is connected with a zero-sequence current transformer CT3, a single-phase current transformer CT8, a single-phase current transformer CT9 and single-phase current transformer CT10, the connection line that described three-phase switch K6 is connected with the connection line that connects three-phase switch K7 and three-phase switch K3 is connected with zero-sequence current transformer CT4, single-phase current transformer CT11, Single-phase current transformer CT12 and single-phase current transformer CT13. Among them, the single-phase current transformer CT1 is used to detect the magnitude of the zero-sequence current compensated after the zero-sequence reactor ARC is connected to the dynamic simulation system, and the zero-sequence current transformer CT2 is used to detect the zero-sequence current of the low-voltage first low-voltage feeder branch Size, zero-sequence current transformer CT3 is used to detect the zero-sequence current of the low-voltage second low-voltage feeder branch, and zero-sequence current transformer CT4 is used to detect the zero-sequence current of the low-voltage third low-voltage feeder branch, single-phase The current transformer CT5 is used to detect the current magnitude of the U-phase of the low-voltage first low-voltage feeder branch, the single-phase current transformer CT6 is used to detect the current magnitude of the V-phase of the low-voltage first low-voltage feeder branch, and the single-phase current transformer CT7 It is used to detect the current of the W-phase of the low-voltage second low-voltage feeder branch, the single-phase current transformer CT8 is used to detect the current of the U-phase of the second low-voltage feeder branch of the low-voltage, and the single-phase current transformer CT9 is used to detect the low-voltage The current magnitude of the V-phase of the second low-voltage feeder branch, the single-phase current transformer CT10 is used to detect the current magnitude of the W-phase of the low-voltage second low-voltage feeder branch, and the single-phase current transformer CT11 is used to detect the low-voltage third low-voltage feeder The current magnitude of the U-phase of the electric branch circuit, the single-phase current transformer CT12 is used to detect the current magnitude of the V-phase of the low-voltage third low-voltage feeder branch, and the single-phase current transformer CT13 is used to detect the low-voltage third low-voltage feeder branch W Phase current; voltage transformer PT1 is used to provide a high-voltage 10kV voltage signal for a dynamic analog circuit of a coal mine power supply and distribution system, and voltage transformer PT2 is used to provide a low-voltage 3300V voltage signal for a dynamic analog circuit of a coal mine power supply and distribution system ;

As shown in Figure 4, in this embodiment, the phase A high-voltage power supply line is composed of a resistor R1, a capacitor C1 and an inductor L1, one end of the inductor L1 is connected to one end of the capacitor C1 and is the first phase of the A-phase high-voltage power supply line One end of the resistor R1 is connected to one end of the inductor L1 and is the end of the A-phase high-voltage power supply line, the other end of the capacitor C1 and the other end of the resistor R1 are grounded; the B-phase high-voltage power supply line is connected by the resistor R2 , capacitor C2 and inductor L2, one end of the inductor L2 is connected to one end of the capacitor C2 and is the first end of the B-phase high-voltage power supply line, and one end of the resistor R2 is connected to one end of the inductor L2 and is the B-phase high-voltage power supply line The other end of the capacitor C2 and the other end of the resistor R2 are both grounded; the C-phase high-voltage power supply line is composed of a resistor R3, a capacitor C3 and an inductor L3, and one end of the inductor L3 is connected to one end of the capacitor C3 and It is the first end of the C-phase high-voltage power supply line. One end of the resistor R3 is connected to one end of the inductor L3 and is the end of the C-phase high-voltage power supply line. The other end of the capacitor C3 and the other end of the resistor R3 are both grounded.

As shown in Figure 4, in this embodiment, the first low-voltage feed branch is composed of the first U-phase low-voltage feed branch 2-2, the first V-phase low-voltage feed branch 2-2 and the first W-phase The first U-phase low-voltage feed branch 2-2 is composed of a resistor R4, a capacitor C4 and an inductor L4, one end of the inductor L4 is connected to one end of the capacitor C4 and is the first The first end of a U-phase low-voltage feed branch 2-2, one end of the resistor R4 is connected to one end of the inductor L4 and is the end of the first U-phase low-voltage feed branch 2-2, and the other end of the capacitor C4 One end and the other end of the resistor R4 are both grounded, and the first V-phase low-voltage feed branch 2-2 is composed of a resistor R5, a capacitor C5 and an inductor L5, one end of the inductor L5 is connected to one end of the capacitor C5 and is the first The first end of a V-phase low-voltage feed branch 2-2, one end of the resistor R5 is connected to one end of the inductor L5 and is the end of the first V-phase low-voltage feed branch 2-2, the other end of the capacitor C5 One end and the other end of the resistor R5 are both grounded, and the first W-phase low-voltage feed branch circuit 2-2 is composed of a resistor R6, a capacitor C6 and an inductor L6, and one end of the inductor L6 is connected to one end of the capacitor C6 and is the first The first end of a W-phase low-voltage feed branch 2-2, one end of the resistor R6 is connected to one end of the inductor L6 and is the end of the first W-phase low-voltage feed branch 2-2, and the other end of the capacitor C6 One end and the other end of the resistor R6 are both grounded; the second low-voltage feed branch is composed of the second U-phase low-voltage feed branch 2-2, the second V-phase low-voltage feed branch 2-2 and the second W-phase low-voltage feed branch Feed branch 2-2, the second U-phase low-voltage feed branch 2-2 is composed of resistor R7, capacitor C7 and inductor L7, one end of the inductor L7 is connected to one end of the capacitor C7 and is the second The first end of the U-phase low-voltage feeding branch 2-2, one end of the resistor R7 is connected to one end of the inductor L7 and is the end of the second U-phase low-voltage feeding branch 2-2, and the other end of the capacitor C7 and the other end of the resistor R7 are both grounded, and the second V-phase low-voltage feed branch circuit 2-2 is composed of a resistor R8, a capacitor C8 and an inductor L8, and one end of the inductor L8 is connected to one end of the capacitor C8 and is the second The first end of the V-phase low-voltage feed branch 2-2, one end of the resistor R8 is connected to one end of the inductor L8 and is the end of the second V-phase low-voltage feed branch 2-2, and the other end of the capacitor C8 and the other end of the resistor R8 are both grounded, and the second W-phase low-voltage feed branch circuit 2-2 is composed of a resistor R9, a capacitor C9 and an inductor L9, one end of the inductor L9 is connected to one end of the capacitor C9 and is the second The first end of the W-phase low-voltage feed branch 2-2, one end of the resistor R9 is connected to one end of the inductor L9 and is the end of the second W-phase low-voltage feed branch 2-2, and the other end of the capacitor C9 and the other end of the resistor R9 are both grounded; the third low-voltage feed branch is composed of the third U-phase low-voltage feed branch 2-2, the third V-phase low-voltage feed branch 2-2 and the third W-phase low-voltage feed branch The electric branch circuit 2-2 is composed of, and the third U-phase low-voltage feed branch circuit 2-2 is composed of a resistor R10, a capacitor C10 and an inductor L 10, one end of the inductor L10 is connected to one end of the capacitor C10 and is the first end of the third U-phase low-voltage feed branch 2-2, and one end of the resistor R10 is connected to one end of the inductor L10 and is the third U The end of the phase low-voltage feeding branch 2-2, the other end of the capacitor C10 and the other end of the resistor R10 are both grounded, and the third V-phase low-voltage feeding branch 2-2 is composed of a resistor R11, a capacitor C11 and an inductor Composed of L11, one end of the inductor L11 is connected to one end of the capacitor C11 and is the first end of the third V-phase low-voltage feed branch 2-2, one end of the resistor R11 is connected to one end of the inductor L11 and is the third V The end of the phase low-voltage feeding branch 2-2, the other end of the capacitor C11 and the other end of the resistor R11 are both grounded, and the third W-phase low-voltage feeding branch 2-2 is composed of a resistor R12, a capacitor C12 and an inductor Composed of L12, one end of the inductor L12 is connected to one end of the capacitor C12 and is the first end of the third W-phase low-voltage feed branch 2-2, one end of the resistor R12 is connected to one end of the inductor L12 and is the third W The other end of the capacitor C12 and the other end of the resistor R12 are grounded.

In this embodiment, the maximum resistance of the sliding rheostat R16 is 5000Ω, and the maximum resistance of the sliding rheostat R17 is 500Ω.

When the utility model is used for dynamic simulation of coal mine power supply and distribution system, the simulation of the following eight situations can be realized:

Situation 1: Load dynamic simulation of coal mine power supply and distribution system, the specific process is as follows:

Step 101, close three-phase switch K1, three-phase switch K3 and three-phase switch K7, open three-phase switch K4, three-phase switch K5 and three-phase switch K6, and dynamically simulate the coal mine power supply and distribution system in a hot standby state;

Step 102, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7, and dynamically simulating that the coal mine power supply and distribution system is in the no-load operation state;

Step 103, adjust the output torque of the magnetic powder brake 3 from small to large, and dynamically simulate the start-up process of the mining equipment;

Step 104, adjusting the output torque of the magnetic powder brake 3 to the rated torque, dynamically simulating that the power supply and distribution system of the coal mine is in a full-load operation state, and dynamically simulating that the power supply and distribution system of the coal mine is in a normal operation state;

Situation 2: Dynamic simulation of the operation mode of the coal mine power supply and distribution system. The specific process is as follows:

Step 201, closing three-phase switch K1, three-phase switch K3, three-phase switch K4, three-phase switch K5, three-phase switch K6 and three-phase switch K7;

Step 202, close the single-phase switch K2, connect the zero-sequence reactor ARC to the dynamic simulation system, and dynamically simulate the operation mode in which the zero-sequence reactor is installed near the transformer in the coal mine power supply and distribution system, that is, the neutral point compensation grounding operation mode;

Step 203, turn on the single-phase switch K2, the zero-sequence reactor ARC exits the dynamic simulation system, and dynamically simulates the operation mode of the coal mine power supply and distribution system without a zero-sequence reactor near the transformer, that is, the neutral point insulation operation mode;

Whether the coal mine power supply and distribution system is connected with a zero-sequence reactor directly affects the normal operation characteristics and fault characteristics of the system. The corresponding operation mode should be selected according to the different power supply systems of the coal mine. Therefore, it is important to carry out dynamic simulation of the operation mode of the coal mine power supply and distribution system. significance.

Situation 3: Dynamic simulation of leakage faults in coal mine power supply and distribution system, the specific process is as follows:

Step 301, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 302, connect the output terminal OUT1 of the gradual leakage simulation circuit to any one of the terminals a~c, slowly adjust the sliding rheostat R16, and dynamically simulate a gradual single-phase leakage fault at the head end of the high-voltage power supply line; The output terminal OUT1 of the gradual leakage simulation circuit is connected to any two terminals of terminals a~c at the same time, and the sliding rheostat R16 is slowly adjusted to dynamically simulate a gradual asymmetric leakage fault at the head end of the high-voltage power supply line; The output terminal OUT1 of the leakage simulation circuit is connected to the terminals a~c at the same time, and the sliding rheostat R16 is slowly adjusted to dynamically simulate a gradual symmetrical leakage fault at the head end of the high-voltage power supply line;

Step 303. Connect the output terminal OUT1 of the gradual leakage simulation circuit to any one of the terminals d to f, slowly adjust the sliding rheostat R16, and dynamically simulate a gradual single-phase leakage fault at the end of the high-voltage power supply line; The output terminal OUT1 of the leakage simulation circuit is connected to any two terminals d~f at the same time, and the sliding rheostat R16 is slowly adjusted to dynamically simulate a gradual asymmetric leakage fault at the end of the high-voltage power supply line; the gradual leakage simulation The output terminal OUT1 of the circuit is connected to the terminals d~f at the same time, and the sliding rheostat R16 is slowly adjusted to dynamically simulate a gradual symmetrical leakage fault at the end of the high-voltage power supply line;

Step 304. Connect the output terminal OUT1 of the gradual leakage simulation circuit to any one of the terminals g~o, slowly adjust the sliding rheostat R16, and dynamically simulate the gradual change at the head end of different low-voltage feeder circuits 2-2 Single-phase leakage fault; connect the output terminal OUT1 of the gradual leakage analog circuit with any two terminals of terminals g~i, or with any two terminals of terminals j~l, or with terminals m~ Any two terminals in o are connected at the same time, slowly adjust the sliding rheostat R16, and dynamically simulate the gradual asymmetric leakage fault of the same line at the head end of different low-voltage feeder branches 2-2; the output terminal of the gradual leakage simulation circuit OUT1 is connected to any one of the terminals g~i and any one of the terminals j~l at the same time, or the output terminal OUT1 of the gradual leakage analog circuit is connected to any one of the terminals g~i The terminal is connected to any one of the terminals m~o at the same time, or the output terminal OUT1 of the gradual leakage simulation circuit is connected to any one of the terminals j~l and any one of the terminals m~o The terminals are connected at the same time, slowly adjust the sliding rheostat R16, and dynamically simulate the asymmetrical leakage faults of different line gradients at the head end of different low-voltage feeder branches 2-2; Simultaneous connection, or simultaneous connection with terminals j~l, or simultaneous connection with terminals m~o, dynamically simulate the gradual symmetrical leakage fault at the head end of different low-voltage feeder circuits 2-2;

Step 305. Connect the output terminal OUT1 of the gradual leakage simulation circuit to any one of the terminals p~x, slowly adjust the sliding rheostat R16, and dynamically simulate the gradual change at the end of different low-voltage feeder branches 2-2. Phase leakage fault; connect the output terminal OUT1 of the gradual leakage analog circuit to any two of the terminals p~r, any two of the terminals s~u or any two of the terminals v~x at the same time, Slowly adjust the sliding rheostat R16 to dynamically simulate the gradual asymmetric leakage fault of the same line at the end of different low-voltage feeder circuits 2-2; connect the output terminal OUT1 of the gradual leakage simulation circuit to any one of the terminals p~r and Connect any one of the terminals s~u at the same time, or connect the output terminal OUT1 of the gradual leakage analog circuit to any one of the terminals p~r and any one of the terminals v~x at the same time, or connect the gradient The output terminal OUT1 of the leakage simulation circuit is connected to any one of the terminals s~u and any one of the terminals v~x at the same time, slowly adjusting the sliding rheostat R16, and dynamically simulating the difference at the end of different low-voltage feeder circuits 2-2 The gradual asymmetric leakage fault of the line; connect the output terminal OUT1 of the gradual leakage simulation circuit to the terminals p~r at the same time, or to the terminals s~u, or to the terminals v~x at the same time, and dynamically simulate different low voltages A gradual symmetrical leakage fault occurs at the end of feeder branch 2-2;

Leakage is a kind of failure with the highest probability of occurrence in the coal mine power supply and distribution system. It is easy to cause personal electric shock and unprepared explosion of the electric detonator. It is highly random and is one of the main failures that affect the safe operation of the system. Therefore, the leakage fault of the coal mine power supply and distribution system Dynamic simulation has important practical significance.

Situation 4: Dynamic simulation of single-phase ground fault in coal mine power supply and distribution system. The specific process is as follows:

Step 401, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 402, connect the first output terminal OUT2 of the short-circuit simulation circuit to any one of the terminals a to c, close the single-phase switch K10 and single-phase switch K13, open the single-phase switch K14, and dynamically simulate high-voltage power supply A single-phase direct ground fault occurs at the head end of the line; close the single-phase switch K10 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the single-phase failure of the first end of the high-voltage power supply line through different resistance transition resistances. ground fault; or connect the second output terminal OUT3 of the short-circuit simulation circuit to any one of the terminals a to c, close the single-phase switch K11 and single-phase switch K13, open the single-phase switch K14, and dynamically simulate high voltage A single-phase direct ground fault occurs at the head end of the power supply line; close the single-phase switch K11 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the single-phase transition resistance with different resistance values at the head end of the high-voltage power supply line or connect the third output terminal OUT4 of the short-circuit simulation circuit to any one of the terminals a to c, close the single-phase switch K12 and single-phase switch K13, open the single-phase switch K14, and dynamically simulate A single-phase direct ground fault occurs at the head end of the high-voltage power supply line; close the single-phase switch K12 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the transition of the single-phase through different resistance values at the head end of the high-voltage power supply line ground fault of the resistor;

Step 403: Connect the first output terminal OUT2 of the short-circuit simulation circuit to any one of the terminals d to f, close the single-phase switch K10 and the single-phase switch K13, open the single-phase switch K14, and dynamically simulate the high-voltage power supply A single-phase direct ground fault occurs at the end of the line; close the single-phase switch K10 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate a single-phase ground fault at the end of the high-voltage power supply line through transition resistances of different resistances ; or connect the second output terminal OUT3 of the short-circuit simulation circuit to any one of the terminals d～f, close the single-phase switch K11 and the single-phase switch K13, open the single-phase switch K14, and dynamically simulate the high-voltage power supply line A single-phase direct grounding fault occurs at the end; close the single-phase switch K11 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate a single-phase grounding fault at the end of the high-voltage power supply line through transition resistances of different resistances; Or connect the third output terminal OUT4 of the short-circuit simulation circuit to any one of the terminals d to f, close the single-phase switch K12 and the single-phase switch K13, and dynamically simulate a single-phase direct grounding fault at the end of the high-voltage power supply line ; Close the single-phase switch K12 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the grounding fault of the single-phase through the transition resistance of different resistance values at the end of the high-voltage power supply line;

Step 404, connect the first output terminal OUT2 of the short circuit simulation circuit to any one of the terminals g~o, close the single-phase switch K10 and single-phase switch K13, open the single-phase switch K14, and dynamically simulate the low-voltage feeder A single-phase direct ground fault occurs at the head end of branch circuit 2-2; close the single-phase switch K10 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the head end of low-voltage feed branch circuit 2-2 When a single-phase ground fault occurs through transition resistors with different resistance values; or connect the second output terminal OUT3 of the short-circuit analog circuit to any one of the terminals g to o, and close the single-phase switch K11 and the single-phase switch K13 , open the single-phase switch K14, and dynamically simulate a single-phase direct ground fault at the head end of the low-voltage feeder branch 2-2; close the single-phase switch K11 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically Simulate a single-phase grounding fault through transition resistors of different resistances at the head end of the low-voltage feeder branch 2-2; or connect the third output terminal OUT4 of the short-circuit simulation circuit to any one of the terminals g to o , close single-phase switch K12 and single-phase switch K13, open single-phase switch K14, and dynamically simulate a single-phase direct ground fault at the head end of low-voltage feeder branch 2-2; close single-phase switch K12 and single-phase switch K14, open single-phase The phase switch K13 slowly adjusts the sliding rheostat R17 to dynamically simulate a single-phase grounding fault at the head end of the low-voltage feeder branch 2-2 through transition resistors with different resistance values;

Step 405, connect the first output terminal OUT2 of the short-circuit simulation circuit to any one of the terminals p~x, close the single-phase switch K10 and single-phase switch K13, open the single-phase switch K14, and dynamically simulate the low-voltage feeder A single-phase direct ground fault occurs at the end of branch circuit 2-2; close the single-phase switch K10 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the single-phase fault at the end of low-voltage feeder branch 2-2. A ground fault through a transition resistor with different resistance values; or connect the second output terminal OUT3 of the short-circuit analog circuit to any one of the terminals p~x, close the single-phase switch K11 and single-phase switch K13, and open The single-phase switch K14 dynamically simulates a single-phase direct ground fault at the end of the low-voltage feeder branch 2-2; closes the single-phase switch K11 and single-phase switch K14, opens the single-phase switch K13, and slowly adjusts the sliding rheostat R17 to dynamically simulate the low-voltage feeder A single-phase grounding fault occurs at the end of the electrical branch 2-2 via transition resistors of different resistances; or connect the third output terminal OUT4 of the short-circuit analog circuit to any one of the terminals p~x to close the single-phase Switch K12 and single-phase switch K13, open single-phase switch K14, dynamically simulate a single-phase direct ground fault at the end of low-voltage feeder branch 2-2; close single-phase switch K12 and single-phase switch K14, open single-phase switch K13, slowly Adjust the sliding rheostat R17 to dynamically simulate a single-phase grounding fault at the end of the low-voltage feeder branch 2-2 through transition resistances of different resistances;

Because the single-phase grounding point current is small and submerged in the large load current, single-phase grounding is the most difficult to identify fault in the coal mine power supply and distribution system, so the dynamic simulation of single-phase ground fault in the coal mine power supply and distribution system is carried out has important practical significance.

Situation 5. Dynamic simulation of short-circuit faults in coal mine power supply and distribution systems. The specific process is as follows:

Step 501, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 502, connecting any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit with the terminals a~c Connect any two terminals separately, close the two corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminals, open the single-phase switch K13 and single-phase switch K14, and dynamically simulate high voltage An asymmetrical direct short-circuit fault occurs at the head end of the power supply line; close two of the corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close the single-phase switch K13 and open the single-phase switch K14 , to dynamically simulate an asymmetrical grounding short-circuit fault at the head end of the high-voltage power supply line; close two of the corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close the single-phase switch K14 and open The single-phase switch K13 slowly adjusts the sliding rheostat R17, and dynamically simulates the asymmetrical grounding short-circuit fault at the head end of the high-voltage power supply line through transition resistors with different resistance values;

Step 503, connecting any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit with the terminals d to f Connect any two terminals separately, close the two corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminals, open the single-phase switch K13 and single-phase switch K14, and dynamically simulate high voltage An asymmetric direct short-circuit fault occurs at the end of the power supply line; close two of the corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close the single-phase switch K13 and open the single-phase switch K14, Dynamically simulate an asymmetrical grounding short-circuit fault at the end of the high-voltage power supply line; close two of the corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close the single-phase switch K14 and open the single-phase The switch K13 slowly adjusts the sliding rheostat R17 to dynamically simulate the asymmetric grounding short-circuit fault at the end of the high-voltage power supply line through the transition resistance of different resistance values;

Step 504, connecting any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit with the terminals g~i Connect any two terminals, or any two terminals among terminals j~l, or any two terminals among terminals m~o, and close single-phase switch K10, single-phase switch K11 and single-phase switch K10. Two of the corresponding output ends of the phase switch K12 are connected to the terminals, open the single-phase switch K13 and single-phase switch K14, and dynamically simulate an asymmetric direct short-circuit fault at the head end of the low-voltage feeder branch 2-2; close the single-phase switch K10, single-phase switch K11 and single-phase switch K12 are two of the corresponding output terminals connected to the terminal, close the single-phase switch K13 and open the single-phase switch K14, and dynamically simulate the abnormal occurrence at the head end of the low-voltage feeder branch 2-2. Symmetrical ground short-circuit fault; close two of the corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close the single-phase switch K14 and open the single-phase switch K13, slowly adjust the sliding rheostat R17 , dynamically simulating the asymmetric grounding short-circuit fault at the head end of the low-voltage feeder branch 2-2 through transition resistors with different resistance values;

Step 505, connecting any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit with the terminals p-r Any two terminals, or any two terminals among terminals s~u, or any two terminals among terminals v~x are respectively connected, and single-phase switch K10, single-phase switch K11 and single-phase switch K10 are closed. Two of the corresponding output ends of the phase switch K12 are connected to the terminals, open the single-phase switch K13 and single-phase switch K14, and dynamically simulate an asymmetrical direct short-circuit fault at the end of the low-voltage feeder branch 2-2; close the single-phase switch K10 1. Two of the corresponding output ends of the single-phase switch K11 and the single-phase switch K12 are connected to the terminal, close the single-phase switch K13 and open the single-phase switch K14, and dynamically simulate the asymmetrical grounding at the end of the low-voltage feeder branch 2-2 Short-circuit fault; close two of the corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close the single-phase switch K14 and open the single-phase switch K13, slowly adjust the sliding rheostat R17, dynamically Simulate the asymmetrical grounding short-circuit fault at the end of the low-voltage feeder branch 2-2 through transition resistors with different resistance values;

Step 506: Connect the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit to the terminals a~c respectively, and close the single-phase switch K10, Single-phase switch K11, single-phase switch K12 and single-phase switch K13, open single-phase switch K14, dynamically simulate a symmetrical metallic short-circuit fault at the head end of the high-voltage power supply line; close single-phase switch K10, single-phase switch K11, single-phase switch K12 And the single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the symmetrical short-circuit fault of the transition resistance with different resistance values at the head end of the high-voltage power supply line;

Step 507: Connect the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit to terminals d to f respectively, and close the single-phase switch K10, Single-phase switch K11, single-phase switch K12 and single-phase switch K13, open single-phase switch K14, and dynamically simulate a symmetrical metallic short-circuit fault at the end of the high-voltage power supply line; close single-phase switch K10, single-phase switch K11, single-phase switch K12 and Single-phase switch K14, open single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the symmetrical short-circuit fault at the end of the high-voltage power supply line through the transition resistance of different resistances;

Step 508: Connect the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit to the connection terminals g~i, or to the connection terminals j~ l. Or connect to terminals m~o respectively, close single-phase switch K10, single-phase switch K11, single-phase switch K12 and single-phase switch K13, open single-phase switch K14, and dynamically simulate low-voltage feeder branch 2-2 A symmetrical metallic short-circuit fault occurs at the terminal; close the single-phase switch K10, single-phase switch K11, single-phase switch K12 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the low-voltage feeder branch 2- 2 A symmetrical short-circuit fault occurs at the head end through transition resistors with different resistance values;

Step 509, connecting the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit to the connection terminals p~r, or to the connection terminals s~r respectively u, or connected to terminals v~x respectively, close single-phase switch K10, single-phase switch K11, single-phase switch K12 and single-phase switch K13, open single-phase switch K14, and dynamically simulate the end of low-voltage feeder branch 2-2 A symmetrical metallic short-circuit fault occurs; close the single-phase switch K10, single-phase switch K11, single-phase switch K12 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the low-voltage feeder branch 2-2 A symmetrical short-circuit fault occurs at the end through transition resistors of different resistances.

Short circuit is the most serious fault in coal mine power supply and distribution system. At present, large-scale power outages in coal mines are mainly caused by short circuit faults. Therefore, the dynamic simulation of short circuit faults in coal mine power supply and distribution system has important practical significance.

Situation 6. Dynamic simulation of leakage protection performance of coal mine power supply and distribution system. The specific process is as follows:

Step 601, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 602, the secondary side winding of the zero-sequence current transformer CT2, the secondary side winding of the zero-sequence current transformer CT3 and the secondary side winding of the zero-sequence current transformer CT4, and the secondary side winding of the voltage transformer PT2 Both are connected to the mine comprehensive protector to be tested;

Step 603: Connect the output terminal OUT1 of the gradual leakage simulation circuit to any one of the terminals g~i, slowly adjust the sliding rheostat R16, and dynamically simulate a single-phase gradual change at the head end of the first low-voltage feeder branch Leakage fault; or connect the output terminal OUT1 of the gradual leakage simulation circuit to any two of the terminals g~i at the same time, slowly adjust the sliding rheostat R16, and dynamically simulate the gradual change of the same line at the first end of the first low-voltage feeder branch or connect the output terminal OUT1 of the gradual leakage simulation circuit to the terminals g~i at the same time, and dynamically simulate the gradual symmetrical leakage fault at the head end of different low-voltage feeder circuits 2-2;

Step 604, check the action of the switch and judge the selective performance of the leakage protection of the mine comprehensive protector to be tested: when the three-phase switch K4 is opened, and the three-phase switch K5 and the three-phase switch K6 do not change the closed state, it is judged to be tested The lateral selection performance of the leakage protection of the mining comprehensive protector is good; when the three-phase switch K4 does not change the closed state, and the three-phase switch K5 or the three-phase switch K6 is opened, it is judged that the lateral selection performance of the leakage protection of the mining comprehensive protector is to be tested Poor; when the three-phase switch K4 does not change the closed state and the three-phase switch K3 is opened, it is judged that the vertical selection performance of the leakage protection of the mine comprehensive protector to be tested is poor;

Step 605. Connect the output end OUT1 of the gradual leakage simulation circuit to any one of the terminals p~r, adjust the resistance value of the sliding rheostat R16 to the maximum value, and dynamically simulate the occurrence of a single at the end of the first low-voltage feeder branch. Phase leakage fault; or connect the output terminal OUT1 of the gradual leakage simulation circuit to any two of the terminals p~r at the same time, adjust the resistance of the sliding rheostat R16 to the maximum value, and dynamically simulate the end of the first low-voltage feeder branch An asymmetric leakage fault of the same line occurs;

Step 606, check the action of the switch and judge the sensitive performance of the leakage protection of the mine comprehensive protector to be tested: when the three-phase switch K4 is open, and the three-phase switch K5 and the three-phase switch K6 do not change the closed state, it is judged to be tested The sensitivity performance of the leakage protection of the comprehensive mine protector is good; when the three-phase switch K4, the three-phase switch K5 and the three-phase switch K6 do not change the closed state, it is judged that the sensitivity performance of the leakage protection of the mine comprehensive protector to be tested is poor;

Leakage protection is one of the three major protections for power supply in coal mines. It is the main measure to ensure the safety of power supply and prevent personal electric shock. Currently, the misoperation rate of leakage protection applied in coal mines remains high. Therefore, dynamic simulation of leakage protection performance in coal mine power supply and distribution systems has important important practical significance.

During specific implementation, it is also possible to set various types of leakage faults in the second low-voltage feeder branch or the third low-voltage feeder branch to dynamically simulate the leakage protection performance of the comprehensive mine protector to be tested.

When various types of leakage faults occur in the second low-voltage feeder branch to test the leakage protection performance of the mine integrated protector to be tested, the specific process is as follows:

Step 607, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 608, the secondary side winding of the zero-sequence current transformer CT2, the secondary side winding of the zero-sequence current transformer CT3 and the secondary side winding of the zero-sequence current transformer CT4, and the secondary side winding of the voltage transformer PT2 Both are connected to the mine comprehensive protector to be tested;

Step 609: Connect the output terminal OUT1 of the gradual leakage simulation circuit to any one of the terminals j~l, slowly adjust the sliding rheostat R16, and dynamically simulate the single-phase gradual change at the head end of the second low-voltage feeder branch Leakage fault; or connect the output terminal OUT1 of the gradual leakage simulation circuit to any two of the terminals j~l at the same time, slowly adjust the sliding rheostat R16, and dynamically simulate the gradual change of the same line at the head end of the second low-voltage feeder branch or connect the output terminal OUT1 of the gradual leakage simulation circuit to the terminals j~l at the same time, and dynamically simulate the gradual symmetrical leakage fault at the head end of different low-voltage feeder circuits 2-2;

Step 6010, check the operation of the switch and judge the selective performance of the leakage protection of the mine comprehensive protector to be tested: when the three-phase switch K5 is open, and the three-phase switch K4 and the three-phase switch K6 do not change the closed state, it is judged to be tested The lateral selection performance of the leakage protection of the mining integrated protector is good; when the three-phase switch K5 does not change the closed state, and the three-phase switch K4 or the three-phase switch K6 is opened, it is judged that the lateral selection performance of the leakage protection of the mining integrated protector is to be tested Poor; when the three-phase switch K5 does not change the closed state and the three-phase switch K3 is opened, it is judged that the longitudinal selection performance of the leakage protection of the mine comprehensive protector to be tested is poor;

Step 6011. Connect the output terminal OUT1 of the gradual leakage simulation circuit to any one of the terminals s~u, adjust the resistance value of the sliding rheostat R16 to the maximum value, and dynamically simulate the occurrence of a single at the end of the second low-voltage feeder branch. Phase leakage fault; or connect the output terminal OUT1 of the gradual leakage simulation circuit to any two of the terminals s~u at the same time, adjust the resistance of the sliding rheostat R16 to the maximum value, and dynamically simulate the end of the second low-voltage feeder branch An asymmetric leakage fault of the same line occurs;

Step 6012, check the action of the switch and judge the sensitive performance of the leakage protection of the mine comprehensive protector to be tested: when the three-phase switch K5 is opened, and the three-phase switch K4 and the three-phase switch K6 do not change the closed state, it is judged to be tested The sensitivity performance of the leakage protection of the integrated mine protector is good; when the three-phase switch K4, the three-phase switch K5 and the three-phase switch K6 do not change the closed state, it is judged that the sensitivity performance of the leakage protection of the comprehensive mine protector to be tested is poor.

When various types of leakage faults occur in the third low-voltage feeder branch to test the leakage protection performance of the mine integrated protector to be tested, the specific process is as follows:

Step 6013, closing three-phase switch K1, three-phase switch K3, three-phase switch K4, three-phase switch K5, three-phase switch K6 and three-phase switch K7; closing single-phase switch K2 or opening single-phase switch K2;

Step 6014, the secondary side winding of the zero-sequence current transformer CT2, the secondary side winding of the zero-sequence current transformer CT3 and the secondary side winding of the zero-sequence current transformer CT4, and the secondary side winding of the voltage transformer PT2 Both are connected to the mine comprehensive protector to be tested;

Step 6015. Connect the output terminal OUT1 of the gradual leakage simulation circuit to any one of the terminals m~o, slowly adjust the sliding rheostat R16, and dynamically simulate a single-phase gradual change at the head end of the third low-voltage feeder branch Leakage fault; or connect the output terminal OUT1 of the gradual leakage simulation circuit to any two of the terminals m~o at the same time, slowly adjust the sliding rheostat R16, and dynamically simulate the gradual change of the same line at the head end of the third low-voltage feeder branch or connect the output terminal OUT1 of the gradual leakage simulation circuit to the terminals m~o at the same time, and dynamically simulate the gradual symmetrical leakage fault at the head end of different low-voltage feeder circuits 2-2;

Step 6016, check the action of the switch and judge the selective performance of the leakage protection of the mine comprehensive protector to be tested: when the three-phase switch K6 is opened, and the three-phase switch K4 and the three-phase switch K5 do not change the closed state, it is judged to be tested The lateral selection performance of the leakage protection of the mining integrated protector is good; when the three-phase switch K6 does not change the closed state, and the three-phase switch K4 or the three-phase switch K5 is opened, it is judged that the lateral selection performance of the leakage protection of the mining integrated protector is to be tested Bad; when the three-phase switch K6 does not change the closed state and the three-phase switch K3 is opened, it is judged that the vertical selection performance of the leakage protection of the mine comprehensive protector to be tested is poor;

Step 6017. Connect the output end OUT1 of the gradual leakage simulation circuit to any one of the connection terminals v~x, adjust the resistance of the sliding rheostat R16 to the maximum value, and dynamically simulate the single occurrence at the end of the third low-voltage feeder branch. Phase leakage fault; or connect the output terminal OUT1 of the gradual leakage simulation circuit to any two of the terminals v~x at the same time, adjust the resistance of the sliding rheostat R16 to the maximum value, and dynamically simulate the end of the third low-voltage feeder branch An asymmetric leakage fault of the same line occurs;

Step 6018, check the action of the switch and judge the sensitive performance of the leakage protection of the mine comprehensive protector to be tested: when the three-phase switch K6 is open, and the three-phase switch K4 and the three-phase switch K6 do not change the closed state, it is judged to be tested The sensitivity performance of the leakage protection of the integrated mine protector is good; when the three-phase switch K4, the three-phase switch K5 and the three-phase switch K6 do not change the closed state, it is judged that the sensitivity performance of the leakage protection of the comprehensive mine protector to be tested is poor.

Situation 7. Dynamic simulation of short-circuit protection performance of coal mine power supply and distribution system. The specific process is as follows:

Step 701, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 702, the secondary side winding of single-phase current transformer CT5, the secondary side winding of single-phase current transformer CT6, the secondary side winding of single-phase current transformer CT7, the secondary side of single-phase current transformer CT8 winding, the secondary side winding of single-phase current transformer CT9, the secondary side winding of single-phase current transformer CT10, the secondary side winding of single-phase current transformer CT11, the secondary side winding of single-phase current transformer CT12 and The secondary side winding of the single-phase current transformer CT13 and the secondary side winding of the voltage transformer PT2 are connected to the comprehensive mine protector to be tested;

Step 703, connecting any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit with the terminals p~r Connect any two terminals separately, close the two corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminals, open the single-phase switch K13 and single-phase switch K14, and dynamically simulate the first An asymmetrical direct short-circuit fault occurs at the end of a low-voltage feeder branch; close two of the corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close the single-phase switch K13 and open the single-phase switch K13 The phase switch K14 dynamically simulates an asymmetrical grounding short-circuit fault at the end of the first low-voltage feeder branch; close the two corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close The single-phase switch K14 is turned on and the single-phase switch K13 is turned on, and the sliding rheostat R17 is slowly adjusted to dynamically simulate an asymmetric grounding short-circuit fault at the end of the first low-voltage feeder branch through transition resistances of different resistances;

Step 704, check the action of the switch and judge the selectivity and sensitivity of the short-circuit protection of the mine comprehensive protector to be tested: when the three-phase switch K4 is opened, and the three-phase switch K5 and the three-phase switch K6 do not change the closed state, It is judged that the lateral selection performance of the short-circuit protection of the mine comprehensive protector to be tested is good; when the three-phase switch K4 does not change the closed state, and the three-phase switch K5 or three-phase switch K6 is opened, it is judged that the short-circuit protection of the mine comprehensive protector to be tested The horizontal selection performance of the comprehensive protector for mining is poor; when the three-phase switch K4 does not change the closed state and the three-phase switch K3 is opened, it is judged that the vertical selection performance of the short-circuit protection of the comprehensive mine protector to be tested is poor; when the three-phase switch K4, the three-phase switch K5 When neither the three-phase switch K6 nor the three-phase switch changes the closed state, it is judged that the sensitivity performance of the short-circuit protection of the mine comprehensive protector to be tested is poor;

Step 705: Connect the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit to the terminals g~i respectively, and close the single-phase switch K10, The single-phase switch K11, single-phase switch K12 and single-phase switch K13 turn on the single-phase switch K14, and dynamically simulate a symmetrical metallic short-circuit fault at the head end of the first low-voltage feeder branch;

Step 706, check the action of the switch and judge the short-circuit protection reliability of the mine integrated protector to be tested: when the three-phase switch K4 is open, and the three-phase switch K5 and the three-phase switch K6 do not change the closed state, it is judged to be tested The reliability of the short-circuit protection of the mining comprehensive protector is good; when the three-phase switch K4 does not change the closed state, the three-phase switch K5 or the three-phase switch K6 is opened, or the three-phase switch K4, the three-phase switch K5 and the three-phase switch K6 are all When the closed state is not changed, it is judged that the reliability of the short-circuit protection of the mine comprehensive protector to be tested is poor;

Short-circuit protection is one of the three major protections for coal mine power supply. It is the main measure to ensure power supply safety and avoid large-scale power outages in coal mines. Currently, the misoperation rate of short-circuit protection used in coal mines remains high. Dynamic simulation has important practical significance.

During specific implementation, it is also possible to set various types of short-circuit faults in the second low-voltage feeder branch or the third low-voltage feeder branch to dynamically simulate the short-circuit protection performance of the mine comprehensive protector to be tested.

When various types of short-circuit faults occur in the second low-voltage feeder branch to test the short-circuit protection performance of the mine integrated protector to be tested, the specific process is as follows:

Step 707, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 708, the secondary side winding of single-phase current transformer CT5, the secondary side winding of single-phase current transformer CT6, the secondary side winding of single-phase current transformer CT7, the secondary side winding of single-phase current transformer CT8 , secondary side winding of single-phase current transformer CT9, secondary side winding of single-phase current transformer CT10, secondary side winding of single-phase current transformer CT11, secondary side winding of single-phase current transformer CT12 and single-phase current transformer CT12 The secondary side winding of the phase current transformer CT13 and the secondary side winding of the voltage transformer PT2 are connected to the mine comprehensive protector to be tested;

Step 709, connecting any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit with the terminals s-u Connect any two terminals separately, close the two corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminals, open the single-phase switch K13 and single-phase switch K14, and dynamically simulate the first An asymmetrical direct short-circuit fault occurs at the end of the second low-voltage feeder branch; close two of the corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close the single-phase switch K13 and open the single-phase switch K13 The phase switch K14 dynamically simulates an asymmetrical grounding short-circuit fault at the end of the second low-voltage feeder branch; close the two corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close The single-phase switch K14 and the single-phase switch K13 are turned on, and the sliding rheostat R17 is slowly adjusted to dynamically simulate the asymmetrical grounding short-circuit fault at the end of the second low-voltage feeder branch through transition resistors with different resistance values;

Step 7010, check the action of the switch and judge the selectivity and sensitivity of the short-circuit protection of the mine comprehensive protector to be tested: when the three-phase switch K5 is opened, and the three-phase switch K4 and the three-phase switch K6 do not change the closed state, It is judged that the lateral selection performance of the short-circuit protection of the mine comprehensive protector to be tested is good; when the three-phase switch K5 does not change the closed state, and the three-phase switch K4 or three-phase switch K6 is opened, it is judged that the short-circuit protection of the mine comprehensive protector to be tested The horizontal selection performance of the comprehensive protector for mining is poor; when the three-phase switch K5 does not change the closed state and the three-phase switch K3 is opened, it is judged that the longitudinal selection performance of the short-circuit protection of the comprehensive mine protector to be tested is poor; when the three-phase switch K4, the three-phase switch K5 When neither the three-phase switch K6 nor the three-phase switch changes the closed state, it is judged that the sensitivity performance of the short-circuit protection of the mine comprehensive protector to be tested is poor;

Step 7011. Connect the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit to the connection terminals j~l respectively, and close the single-phase switch K10, The single-phase switch K11, single-phase switch K12 and single-phase switch K13 turn on the single-phase switch K14, and dynamically simulate a symmetrical metallic short-circuit fault at the head end of the second low-voltage feeder branch;

Step 7012, check the action of the switch and judge the short-circuit protection reliability of the mine integrated protector to be tested: when the three-phase switch K5 is open, and the three-phase switch K4 and the three-phase switch K6 do not change the closed state, it is judged to be tested The reliability of the short-circuit protection of the comprehensive mine protector is good; when the three-phase switch K5 does not change the closed state, the three-phase switch K4 or the three-phase switch K6 is opened, or the three-phase switch K4, the three-phase switch K5 and the three-phase switch K6 are all When the closed state is not changed, it is judged that the reliability performance of the short-circuit protection of the mine comprehensive protector to be tested is poor.

When various types of short-circuit faults occur in the third low-voltage feeder branch to test the short-circuit protection performance of the mine integrated protector to be tested, the specific process is as follows:

Step 7013, closing three-phase switch K1, three-phase switch K3, three-phase switch K4, three-phase switch K5, three-phase switch K6 and three-phase switch K7; closing single-phase switch K2 or opening single-phase switch K2;

Step 7014, the secondary side winding of single-phase current transformer CT5, the secondary side winding of single-phase current transformer CT6, the secondary side winding of single-phase current transformer CT7, the secondary side winding of single-phase current transformer CT8 , secondary side winding of single-phase current transformer CT9, secondary side winding of single-phase current transformer CT10, secondary side winding of single-phase current transformer CT11, secondary side winding of single-phase current transformer CT12 and single-phase current transformer CT12 The secondary side winding of the phase current transformer CT13 and the secondary side winding of the voltage transformer PT2 are connected to the mine comprehensive protector to be tested;

Step 7015, connecting any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit with the terminals v~x Connect any two terminals separately, close the two corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminals, open the single-phase switch K13 and single-phase switch K14, and dynamically simulate the first An asymmetric direct short-circuit fault occurs at the end of the three low-voltage feeder branches; close two of the corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close the single-phase switch K13 and open the single-phase switch K13 The phase switch K14 dynamically simulates an asymmetrical grounding short-circuit fault at the end of the third low-voltage feeder branch; close the two corresponding output terminals of the single-phase switch K10, single-phase switch K11 and single-phase switch K12 connected to the terminal, close The single-phase switch K14 and the single-phase switch K13 are turned on, and the sliding rheostat R17 is slowly adjusted to dynamically simulate an asymmetrical grounding short-circuit fault at the end of the third low-voltage feeder branch through transition resistances of different resistances;

Step 7016, check the action of the switch and judge the selection performance and sensitivity performance of the short-circuit protection of the mine integrated protector to be tested: when the three-phase switch K6 is opened, and the three-phase switch K4 and the three-phase switch K5 do not change the closed state, It is judged that the lateral selection performance of the short-circuit protection of the mine comprehensive protector to be tested is good; when the three-phase switch K6 does not change the closed state, and the three-phase switch K4 or three-phase switch K5 is opened, it is judged that the short-circuit protection of the mine comprehensive protector to be tested The horizontal selection performance of the comprehensive protector to be tested is good or bad; when the three-phase switch K6 does not change the closed state and the three-phase switch K3 is opened, it is judged that the vertical selection performance of the short-circuit protection of the mine comprehensive protector to be tested is good or bad; when the three-phase switch K4, three-phase When both the switch K5 and the three-phase switch K6 do not change the closed state, it is judged that the sensitivity performance of the short-circuit protection of the mine comprehensive protector to be tested is poor;

Step 7017: Connect the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit to terminals m~o respectively, and close the single-phase switch K10, The single-phase switch K11, single-phase switch K12 and single-phase switch K13 turn on the single-phase switch K14, and dynamically simulate a symmetrical metallic short-circuit fault at the head end of the second low-voltage feeder branch;

Step 7018, check the action of the switch and judge the reliability of the short-circuit protection of the comprehensive mine protector to be tested: when the three-phase switch K6 is open, and the three-phase switch K4 and the three-phase switch K5 do not change the closed state, it is judged to be tested The reliability of the short-circuit protection of the comprehensive mine protector is good; when the three-phase switch K6 does not change the closed state, the three-phase switch K4 or the three-phase switch K5 is opened, or the three-phase switch K4, the three-phase switch K5 and the three-phase switch K6 are all When the closed state is not changed, it is judged that the reliability performance of the short-circuit protection of the mine integrated protector to be tested is poor.

Situation 8. Dynamic simulation of single-phase grounding protection of coal mine power supply and distribution system. The specific process is as follows:

Step 801, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 802, the secondary side winding of the zero-sequence current transformer CT2, the secondary side winding of the zero-sequence current transformer CT3 and the secondary side winding of the zero-sequence current transformer CT4, and the secondary side winding of the voltage transformer PT2 Both are connected to the mine comprehensive protector to be tested;

Step 803: Connect the first output terminal OUT2 of the short-circuit simulation circuit to any one of the terminals g~i, close the single-phase switch K10 and the single-phase switch K13, and dynamically simulate the first low-voltage feeder branch first When a single-phase direct ground fault occurs at the terminal, close the single-phase switch K10 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the single-phase transition through different resistance values at the head end of the first low-voltage feeder branch ground fault of the resistor; or connect the second output terminal OUT3 of the short-circuit simulation circuit to any one of the terminals g~i, close the single-phase switch K11 and the single-phase switch K13, and dynamically simulate the first low-voltage feed When a single-phase direct ground fault occurs at the head end of the branch, close the single-phase switch K11 and single-phase switch K14, open the single-phase switch K13, and slowly adjust the sliding rheostat R17 to dynamically simulate the single-phase fault at the head end of the first low-voltage feeder branch. The grounding fault of the resistance transition resistance; or connect the third output terminal OUT4 of the short-circuit simulation circuit to any one of the terminals g～i, close the single-phase switch K12 and the single-phase switch K13, and dynamically simulate the first When a single-phase direct ground fault occurs at the head end of the low-voltage feeder branch, close the single-phase switch K12 and single-phase switch K14, open the single-phase switch K13, and slowly adjust the sliding rheostat R17 to dynamically simulate a single-phase fault at the head end of the first low-voltage feeder branch. Phase-to-earth faults through transition resistances of different resistances;

Step 804, check the action of the switch and judge the single-phase grounding protection performance of the mine comprehensive protector to be tested: when the three-phase switch K4 is opened, and the three-phase switch K5 and the three-phase switch K6 do not change the closed state, it is judged as a standby The horizontal selection performance of the single-phase grounding protection of the test mine comprehensive protector is good; when the three-phase switch K4 does not change the closed state, and the three-phase switch K5 or three-phase switch K6 is turned on, it is judged that the mine comprehensive protector to be tested is single-phase ground The horizontal selection performance of the protection is poor; when the three-phase switch K4 does not change the closed state and the three-phase switch K3 is opened, it is judged that the longitudinal selection performance of the single-phase grounding protection of the mine comprehensive protector to be tested is poor.

Single-phase grounding protection is one of the three major protections for coal mine power supply. It is the main measure to ensure power supply safety and reduce the probability of short-circuit faults. Currently, the misoperation rate of single-phase grounding protection applied in coal mines remains high. The dynamic simulation of single-phase grounding protection has important practical significance.

During specific implementation, various types of single-phase grounding faults in the second low-voltage feeder branch or the third low-voltage feeder branch can also be set to dynamically simulate the single-phase grounding protection performance of the mine integrated protector to be tested.

When various types of short-circuit faults occur in the second low-voltage feeder branch to test the single-phase grounding protection performance of the mine integrated protector to be tested, the specific process is as follows:

Step 805, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 806, the secondary side winding of the zero-sequence current transformer CT2, the secondary side winding of the zero-sequence current transformer CT3 and the secondary side winding of the zero-sequence current transformer CT4, and the secondary side winding of the voltage transformer PT2 Both are connected to the mine comprehensive protector to be tested;

Step 807: Connect the first output terminal OUT2 of the short-circuit simulation circuit to any one of the terminals j~l, close the single-phase switch K10 and the single-phase switch K13, and dynamically simulate the first of the second low-voltage feeder branch When a single-phase direct ground fault occurs at the terminal, close the single-phase switch K10 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the single-phase transition through different resistance values at the first end of the second low-voltage feeder branch ground fault of the resistor; or connect the second output terminal OUT3 of the short-circuit simulation circuit to any one of the terminals j~l, close the single-phase switch K11 and the single-phase switch K13, and dynamically simulate the second low-voltage feed When a single-phase direct ground fault occurs at the head end of the branch, close the single-phase switch K11 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the single-phase fault at the head end of the second low-voltage feeder branch. The grounding fault of the resistance transition resistance; or connect the third output terminal OUT4 of the short-circuit simulation circuit to any one of the terminals j～l, close the single-phase switch K12 and the single-phase switch K13, and dynamically simulate the second When a single-phase direct ground fault occurs at the head end of the low-voltage feeder branch, close the single-phase switch K12 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate a single-phase fault at the head end of the second low-voltage feeder branch. Phase-to-earth faults through transition resistances of different resistances;

Step 808, check the action of the switch and judge the single-phase grounding protection performance of the mine integrated protector to be tested: when the three-phase switch K5 is opened, and the three-phase switch K4 and the three-phase switch K6 do not change the closed state, it is judged that it is to be tested. The horizontal selection performance of the single-phase grounding protection of the test mine comprehensive protector is good; when the three-phase switch K5 does not change the closed state, and the three-phase switch K4 or three-phase switch K6 is turned on, it is judged that the mine comprehensive protector to be tested is single-phase ground The horizontal selection performance of the protection is poor; when the three-phase switch K5 does not change the closed state and the three-phase switch K3 is opened, it is judged that the longitudinal selection performance of the single-phase grounding protection of the mine comprehensive protector to be tested is poor.

When various types of short-circuit faults occur in the third low-voltage feeder branch to test the single-phase grounding protection performance of the mine integrated protector to be tested, the specific process is as follows:

Step 809, closing the three-phase switch K1, the three-phase switch K3, the three-phase switch K4, the three-phase switch K5, the three-phase switch K6 and the three-phase switch K7; closing the single-phase switch K2 or opening the single-phase switch K2;

Step 8010, the secondary side winding of the zero-sequence current transformer CT2, the secondary side winding of the zero-sequence current transformer CT3 and the secondary side winding of the zero-sequence current transformer CT4, and the secondary side winding of the voltage transformer PT2 Both are connected to the mine comprehensive protector to be tested;

Step 8011, connect the first output terminal OUT2 of the short-circuit simulation circuit to any one of the terminals m~o, close the single-phase switch K10 and the single-phase switch K13, and dynamically simulate the first of the third low-voltage feeder branch When a single-phase direct ground fault occurs at the terminal, close the single-phase switch K10 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the single-phase transition through different resistance values at the head end of the third low-voltage feeder branch ground fault of the resistor; or connect the second output terminal OUT3 of the short-circuit simulation circuit to any one of the terminals m to o, close the single-phase switch K11 and the single-phase switch K13, and dynamically simulate the third low-voltage feed When a single-phase direct ground fault occurs at the head end of the branch, close the single-phase switch K11 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate the single-phase fault at the head end of the third low-voltage feeder branch. The grounding fault of the resistance transition resistance; or connect the third output terminal OUT4 of the short-circuit simulation circuit to any one of the terminals m to o, close the single-phase switch K12 and the single-phase switch K13, and dynamically simulate the third When a single-phase direct ground fault occurs at the head end of the low-voltage feeder branch, close the single-phase switch K12 and single-phase switch K14, open the single-phase switch K13, slowly adjust the sliding rheostat R17, and dynamically simulate a single-phase fault at the head end of the third low-voltage feeder branch. Phase-to-earth faults through transition resistances of different resistances;

Step 8012, check the action of the switch and judge the single-phase grounding protection performance of the mine integrated protector to be tested: when the three-phase switch K6 is open, and the three-phase switch K4 and the three-phase switch K5 do not change the closed state, it is judged to be to be tested. The horizontal selection performance of the single-phase grounding protection of the comprehensive mine protector tested is good; when the three-phase switch K6 does not change the closed state, and the three-phase switch K4 or the three-phase switch K5 is opened, it is judged as the single-phase protection of the mine comprehensive protector to be tested. The horizontal selection performance of the grounding protection is poor; when the three-phase switch K6 does not change the closed state, and the three-phase switch K3 is opened, it is judged that the vertical selection performance of the single-phase grounding protection of the mine comprehensive protector to be tested is poor.

In the above eight cases, when the three-phase switch K7 is open, it is an ideal dynamic simulation of the coal mine power supply and distribution system without harmonics; , The power quality pollution of the traction equipment to the power supply system is used for the dynamic simulation of the coal mine power supply and distribution system under the condition of severe power supply quality pollution. In addition, when the three-phase switch K7 is closed, the simulation system can also be used to test the control effect of the harmonic control device.

In this embodiment, the maximum resistance of the sliding rheostat R16 is 5000Ω, and the range of resistance is 1000Ω˜5000Ω; the maximum resistance of the sliding rheostat R17 is 500Ω. When the resistance of the sliding rheostat R16 is 1000 ohms, it simulates a personal electric shock fault.

The above are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any simple modifications, changes and equivalent structural changes made to the above embodiments according to the technical essence of the present utility model still belong to Within the scope of protection of the technical solution of the utility model.

Claims (5)

1. A dynamic analog circuit of a coal mine power supply and distribution system, characterized in that: it comprises a high-voltage power supply circuit (1) for outputting power supply after the 380V voltage is transformed into a 10kV voltage and a 10kV power supply circuit (1) for outputting the high-voltage power supply circuit (1) A low-voltage feeder circuit (2) for outputting power after the voltage is converted to 3300V, and a magnetic powder brake (3) for simulating loads and a fault simulation circuit connected to the high-voltage power supply circuit (1) or the low-voltage feeder circuit (2) ( 4); the high-voltage power supply circuit (1) is connected to the 380V mains power transmission line (5), and the low-voltage feed circuit (2) includes a step-down circuit (2-1) for converting the 10kV voltage into a 3300V voltage and the low-voltage feed branch (2-2) connected to the step-down circuit (2-1), and the harmonic source connected to both the step-down circuit (2-1) and the low-voltage feed branch (2-2) (2-3), the magnetic powder brake (3) is connected to the low-voltage feeder branch (2-2); The high-voltage power supply circuit (1) includes a step-up transformer T1 for converting 380V voltage to 10kV voltage, a high-voltage power supply line and a zero-sequence reactor ARC, the step-up transformer T1 is a three-phase double-winding transformer, and the step-up transformer T1 The primary side winding of the step-up transformer T1 is a delta connection, the secondary side winding of the step-up transformer T1 is a star connection, and the primary side winding of the step-up transformer T1 is connected to the 380V mains transmission line through a three-phase switch K1 (5) connection, one end of the zero-sequence reactor ARC is connected to the neutral point of the secondary side winding of the step-up transformer T1 through a single-phase switch K2, and the high-voltage power supply line is composed of a phase A high-voltage power supply line and a B-phase high-voltage power supply line. The power supply line and the C-phase high-voltage power supply line are composed. The first end of the A-phase high-voltage power supply line is terminal a and is connected to the first terminal of the secondary side winding of the step-up transformer T1. The B-phase high-voltage power supply line is The first end is terminal b and connected to the second terminal of the secondary side winding of the step-up transformer T1; the third terminal connection; The step-down circuit (2-1) is composed of a step-down transformer T2, the step-down transformer T2 is a three-phase double-winding transformer, the primary side winding of the step-down transformer T2 is a delta connection, and the step-down transformer The secondary side winding of T2 is star-connected, and the number of the low-voltage feeding branches (2-2) is three, which are respectively the first low-voltage feeding branch, the second low-voltage feeding branch and the third low-voltage feeding branch The feeding branch circuit, the three terminals of the primary side winding of the step-down transformer T2 are respectively connected to the end of the A-phase high-voltage power supply line, the end of the B-phase high-voltage power supply line and the C-phase high-voltage power supply line Terminal connection, the end of the A-phase high-voltage power supply line, the end of the B-phase high-voltage power supply line and the end of the C-phase high-voltage power supply line are respectively terminal d, terminal e and terminal f, and the harmonic The source (2-3) is connected to the three terminals of the secondary side winding of the step-down transformer T2 through the three-phase switch K7 and the three-phase switch K3 connected in series in sequence, and the first low-voltage feeding branch is connected through the three-phase The switch K4 is connected to the connection line connecting the three-phase switch K7 and the three-phase switch K3, and the second low-voltage feeder branch is connected to the connection line connecting the three-phase switch K7 and the three-phase switch K3 through the three-phase switch K5, and the The third low-voltage feeder branch is connected to the connection line connecting the three-phase switch K7 and the three-phase switch K3 through the three-phase switch K6, and the three-phase input ends of the first low-voltage feeder branch are respectively terminal g, terminal h and connection terminal i, the three-phase input terminals of the second low-voltage feed branch are connection terminal j, connection terminal k and connection terminal l respectively, and the three-phase input terminals of the third low-voltage feed branch are respectively Connecting terminal m, connecting terminal n and connecting terminal o, the three-phase output ends of the first low-voltage feeder branch are respectively connecting terminal p, connecting terminal q and connecting terminal r, the second low-voltage feeding branch The three-phase output terminals are terminal s, terminal t and terminal u respectively, and the three-phase output terminals of the third low-voltage feeder branch are terminal v, terminal w and terminal x respectively; The fault simulation circuit (4) includes a gradual leakage simulation circuit and a short circuit simulation circuit, the gradual leakage simulation circuit is composed of a single-phase switch K9 and a sliding rheostat R16, the sliding end of the sliding rheostat R16 is grounded, and the sliding rheostat R16 is connected to the ground. A fixed end of the rheostat R16 is connected with one end of the single-phase switch K9, and the other end of the single-phase switch K9 is the output terminal OUT1 of the gradual leakage analog circuit; the short-circuit analog circuit is composed of the sliding rheostat R17, the single-phase switch K10, Single-phase switch K11, single-phase switch K12, single-phase switch K13 and single-phase switch K14, one fixed end of the sliding rheostat R17 passes through single-phase switch K14, one end of single-phase switch K10, one end of single-phase switch K11, One end of the single-phase switch K12 is connected to one end of the single-phase switch K13, the sliding end of the sliding rheostat R17 and the other end of the single-phase switch K13 are grounded, and the other end of the single-phase switch K10 is the first short-circuit analog circuit. output terminal OUT2, the other end of the single-phase switch K11 is the second output terminal OUT3 of the short-circuit analog circuit, and the other end of the single-phase switch K12 is the third output end OUT4 of the short-circuit analog circuit; The output terminal OUT1 of the circuit is connected with terminals a~c or any one of them, any two terminals, or with terminals d~f or any one of them, any two terminals, or with terminals g~i or any of them One, any two terminals, or with terminals j~l or any one of them, any two terminals, or with terminals m~o or any one of them, any two terminals, or with terminals p~ r or any one of them, any two terminals, or connected to terminals s~u or any one of them, any two terminals, or connected to terminals v~x or any one of them, any two terminals; Any one of the first output end OUT2 of the short-circuit analog circuit, the second output end OUT3 of the short-circuit analog circuit and the third output end OUT4 of the short-circuit analog circuit is connected to any one of the connection terminals a～x, Or any two output terminals of the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit and any two of the connection terminals a～c Connecting terminal, or any two connecting terminals among connecting terminals d~f, or connecting any two connecting terminals among connecting terminals g~i, or connecting any two connecting terminals among connecting terminals j~l, or connecting with Any two of the terminals m~o, or any two of the terminals p~r, or any two of the terminals s~u, or any two of the terminals v~x Any two terminals in the short-circuit analog circuit are connected, or the first output terminal OUT2 of the short-circuit analog circuit, the second output terminal OUT3 of the short-circuit analog circuit, and the third output terminal OUT4 of the short-circuit analog circuit are respectively connected to the terminals a~c, or Respectively with terminal d ～f, respectively with terminals g～i, or respectively with terminals j～l, or respectively with terminals m～o, or respectively with terminals p～r, or respectively with terminals s～u, or respectively Connect with terminals v~x. 2. The dynamic analog circuit of a coal mine power supply and distribution system according to claim 1, wherein a single-phase current mutual inductance is connected to the connection line between the single-phase switch K2 and the secondary side winding of the step-up transformer T1 CT1, the connection line between the high-voltage power supply line and the secondary side winding of the step-up transformer T1 is connected with a voltage transformer PT1; the three-phase switch K3 and the three phases of the secondary side winding of the step-down transformer T2 A voltage transformer PT2 is connected to the connecting line of the terminal, and a zero-sequence current transformer CT2 and a single-phase current mutual inductor are connected to the connecting line connecting the three-phase switch K4 to the connecting line connecting the three-phase switch K7 and the three-phase switch K3. CT5, single-phase current transformer CT6 and single-phase current transformer CT7, the connection line connected between the three-phase switch K5 and the connection line connecting three-phase switch K7 and three-phase switch K3 is connected with a zero-sequence current transformer CT3 , single-phase current transformer CT8, single-phase current transformer CT9 and single-phase current transformer CT10, described three-phase switch K6 is connected with zero Sequence current transformer CT4, single-phase current transformer CT11, single-phase current transformer CT12 and single-phase current transformer CT13. 3. The dynamic analog circuit of a kind of coal mine power supply and distribution system according to claim 1, characterized in that: the A-phase high-voltage power supply line is composed of a resistor R1, a capacitor C1 and an inductor L1, and one end of the inductor L1 is connected to the capacitor One end of C1 is connected to the first end of the A-phase high-voltage power supply line, one end of the resistor R1 is connected to one end of the inductor L1 and is the end of the A-phase high-voltage power supply line, the other end of the capacitor C1 is connected to the other end of the resistor R1 Both are grounded; the B-phase high-voltage power supply line is composed of a resistor R2, a capacitor C2 and an inductor L2, one end of the inductor L2 is connected to one end of the capacitor C2 and is the first end of the B-phase high-voltage power supply line, and one end of the resistor R2 It is connected to one end of the inductor L2 and is the end of the B-phase high-voltage power supply line, and the other end of the capacitor C2 and the other end of the resistor R2 are both grounded; the C-phase high-voltage power supply line is composed of a resistor R3, a capacitor C3 and an inductor L3. One end of the inductance L3 is connected to one end of the capacitor C3 and is the first end of the C-phase high-voltage power supply line, one end of the resistor R3 is connected to one end of the inductance L3 and is the end of the C-phase high-voltage power supply line, and the capacitor C3 The other end and the other end of the resistor R3 are both grounded. 4. The dynamic analog circuit of a coal mine power supply and distribution system according to claim 1, characterized in that: the first low-voltage feed branch is composed of the first U-phase low-voltage feed branch, the first V-phase low-voltage feed branch and the first W-phase low-voltage feed branch, the first U-phase low-voltage feed branch is composed of a resistor R4, a capacitor C4 and an inductor L4, one end of the inductor L4 is connected to one end of the capacitor C4 and is the first The first end of a U-phase low-voltage feed branch, one end of the resistor R4 is connected to one end of the inductor L4 and is the end of the first U-phase low-voltage feed branch, the other end of the capacitor C4 and the other end of the resistor R4 Both ends are grounded, and the first V-phase low-voltage feed branch is composed of a resistor R5, a capacitor C5, and an inductor L5. One end of the inductor L5 is connected to one end of the capacitor C5 and is the first V-phase low-voltage feed branch. One end of the resistor R5 is connected to one end of the inductor L5 and is the end of the first V-phase low-voltage feeder branch, the other end of the capacitor C5 and the other end of the resistor R5 are both grounded, and the first W-phase The low-voltage feed branch is composed of a resistor R6, a capacitor C6, and an inductor L6. One end of the inductor L6 is connected to one end of the capacitor C6 and is the first end of the first W-phase low-voltage feed branch. One end of the resistor R6 is connected to the inductor One end of L6 is connected and is the end of the first W-phase low-voltage feeder branch, the other end of the capacitor C6 and the other end of the resistor R6 are grounded; the second low-voltage feeder branch is fed by the second U-phase low-voltage feeder Branch, the second V-phase low-voltage feed branch and the second W-phase low-voltage feed branch, the second U-phase low-voltage feed branch is composed of a resistor R7, a capacitor C7 and an inductor L7, the inductor L7 One end is connected to one end of the capacitor C7 and is the first end of the second U-phase low-voltage feeding branch, and one end of the resistor R7 is connected to one end of the inductor L7 and is the end of the second U-phase low-voltage feeding branch. The other end of the capacitor C7 and the other end of the resistor R7 are both grounded, and the second V-phase low-voltage feed branch is composed of a resistor R8, a capacitor C8 and an inductor L8, and one end of the inductor L8 is connected to one end of the capacitor C8 and is the first The first end of the two V-phase low-voltage feeding branches, one end of the resistor R8 is connected to one end of the inductor L8 and is the end of the second V-phase low-voltage feeding branch, the other end of the capacitor C8 and the other end of the resistor R8 Both ends are grounded, and the second W-phase low-voltage feed branch is composed of a resistor R9, a capacitor C9, and an inductor L9, and one end of the inductor L9 is connected to one end of the capacitor C9 and is the first of the second W-phase low-voltage feed branch. end, one end of the resistor R9 is connected to one end of the inductor L9 and is the end of the second W-phase low-voltage feeder branch, the other end of the capacitor C9 and the other end of the resistor R9 are both grounded; the third low-voltage feeder The electrical branch is composed of a third U-phase low-voltage feeding branch, a third V-phase low-voltage feeding branch and a third W-phase low-voltage feeding branch, and the third U-phase low-voltage feeding branch is composed of a resistor R10 and a capacitor C10 Composed of an inductor L10, one end of the inductor L10 is connected to one end of the capacitor C10 and is the first end of the third U-phase low-voltage feeder branch, and one end of the resistor R10 is connected to one end of the inductor L10 Connected and is the end of the third U-phase low-voltage feed branch, the other end of the capacitor C10 and the other end of the resistor R10 are both grounded, and the third V-phase low-voltage feed branch is composed of a resistor R11, a capacitor C11 and an inductor L11 One end of the inductor L11 is connected to one end of the capacitor C11 and is the first end of the third V-phase low-voltage feed branch, one end of the resistor R11 is connected to one end of the inductor L11 and is the third V-phase low-voltage feed At the end of the branch, the other end of the capacitor C11 and the other end of the resistor R11 are both grounded, and the third W-phase low-voltage feed branch is composed of a resistor R12, a capacitor C12 and an inductor L12, and one end of the inductor L12 is connected to the capacitor One end of C12 is connected to the first end of the third W-phase low-voltage feed branch, one end of the resistor R12 is connected to one end of the inductor L12 and is the end of the third W-phase low-voltage feed branch, and the capacitor C12 The other end and the other end of the resistor R12 are both grounded. 5. The dynamic analog circuit of a coal mine power supply and distribution system according to claim 1, wherein the maximum resistance of the sliding rheostat R16 is 5000Ω, and the maximum resistance of the sliding rheostat R17 is 500Ω.