RU1777200C - Device for automatic control of parallel-running power transformers in double-transformer substation - Google Patents

Abstract

The essence of use: the device contains a control unit for the number of parallel operating power transformers of the substation and OR logic elements, the outputs of which are connected to the executive unit, and the inputs are connected to the control unit and control units for current transformer overload modes, which control the shutdown of transformers with time delays not exceeding requirements of the rules of technical operation and GOST at various current transformer overload ratios. 3 ill.

Description

The invention relates to the control of modes of power system elements and is intended to automatically control the number of parallel power transformer substations in order to maintain a mode of minimal losses and to control current transformer overload conditions.

A device is known for controlling the number of parallel-running transformers of a two-transformer substation (AS I. 1127042, publ. B.I. No. 44 of 10.31.84), containing an energy meter with a pulse sensor and with inputs for connecting to the voltage of the substation and to the load current of one transformer, connected to a pulse counter with counting and zero inputs, two outputs of which are connected to single inputs of triggers, the output of the first trigger is directly, and the second through a logic element is NOT connected to the first inputs of the logical ementov And, the outputs of which are connected to the outputs of the operation unit, wherein the zero-input pulse counter and triggers and second inputs of the AND gates connected to outputs of the sensor loop.

The disadvantage of this device is the low reliability due to the uneven operating time of the two power transformers of the two-transformer substation and the lack of control over the overload conditions of the substation current transformers.

A device is also known for automatically controlling the number of parallel-running power transformers of a two-transformer substation (a, c, N ° 1185492, publ. B.I.

x | vi vi

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No. 38 dated 10.15.85), containing two energy meters with a pulse sensor and with inputs for connecting to the voltage of the substation and the load current of the transformers, a pulse counter, five triggers, logic elements NOT and AND, an executive unit, a cycle master, a switching unit and a source for setting the initial state, wherein the AND gates are three-input, and the outputs of the energy meter are connected to the pulse counter input through a switching unit, the outputs of the AND gates are connected to the counting inputs of the third and fourth triggers, the outputs of which are connected to the outputs of the executive unit, the zero inputs of the third, fourth and fifth triggers and the switching unit are connected to the source of the installation signal in the initial state, the single and zero inputs of the fifth trigger are connected to the outputs of the logical elements AND, and its outputs are connected to the third inputs of the logical elements AND, the control input of the switching unit is connected to the output of the logical element And in the disconnection channel of the power transformer, The disadvantage of this device is low by ezhnost in connection with the lack of control modes transformer overcurrent.

The purpose of the invention is to increase the reliability of a two-transformer substation by introducing units that control current transformer overload conditions in a two-transformer substation.

This goal is achieved by the fact that in a known device for automatically controlling the number of parallel-running power transformers of a two-transformer substation, containing two energy meters with a pulse sensor and inputs for connecting to the voltage of the substation and the load current of the transformers, a pulse counter, five triggers, logical elements NOT and AND, an executive unit, a cycle master, a switching unit, and an initial state setting source, wherein the AND elements are three-input, and the outputs of the energy meter are connected via a switching unit to

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the input of the pulse counter, the two outputs of which are connected to the unit inputs of the first two triggers, the output of the first trigger is directly, and the second through the logic element are NOT connected respectively to the second and third inputs of AND gates, the outputs of which are connected to the counting inputs of the third and fourth triggers , the zero input of the pulse counter, the first input of the first And element, the second input of the second And element, as well as the zero inputs of the first two triggers are connected to the outputs of the cycle master, the zero inputs of the third, the fourth and fifth triggers and the switching unit are connected to the source of the installation signal in the initial state, the single and zero inputs of the fifth trigger are connected to the outputs of the logical elements AND, and the control input of the switching unit is connected to the output of the logical element And in the disconnection channel of the power transformer, in addition, two two-input OR elements, two four-input OR elements, as well as two control units for transformer overload modes were introduced, and the outputs of the four OR elements are connected to unit, and the first inputs of two-input OR elements are connected respectively to the unit and zero outputs of the third trigger, and the second inputs of the first two elements OR are connected to the fourth outputs of the respective control units for transformer overload conditions, the first inputs of two four-input OR elements are connected respectively to zero and single outputs the fourth trigger, and the second, third and fourth inputs of the four-input elements OR are connected to the first three outputs of the corresponding control units transformer overload presses, each of which contains three zero-elements, a timer, six two-input AND elements, two two-input OR elements, four triggers, a current-frequency converter, two time delay elements, six pulse counters with counting and reset enable inputs, an adder and a storage register with inputs for recording information and shear, with all zero-organs and a current-frequency converter connected by inputs to current load transformers, the output of the first zero-organ connected through the first input of the first element OR to the enable input of the first pulse counter, the output of the second zero-organ is connected to the first input of the first AND element, the output of which is connected to the second input of the first OR element, and the output of the current-frequency converter is connected to the inputs of the first and second pulse counter, the output of the first pulse counter , Which is the first output of the mode control unit, transformer overload, is connected to the second input of the corresponding four-input OR element, and the output of the second pulse counter is connected to the input of the register nor whose output is connected to the adder connected by its output to the first input of the second element And, the output of which is connected to the single input of the first trigger, the zero output of which is connected to the second input of the first element And, and the single output is connected to the enable input of the third pulse counter, the output is clock timer pulses is connected to the unit input of the second trigger, the unit output of which is connected to the first input of the third element And, the second input of which is connected to the output of the second timer pulses, the stroke of the third AND element is connected to the input of the fourth pulse counter and to the shift input of the storage register, and the output of the fourth pulse counter is connected to its reset input and to the zero input of the second trigger, the zero output of which is connected to the recording input of the storage register and to the first time delay element, whose output is connected to the reset input of the second pulse counter, the minute output of the timer is connected to the input of the third pulse counter and to the first input of the fourth AND element, to the second input of which the output of the third null organ is switched on, and the output of the fourth element And is connected to the second input of the second element And, as well as to the input of the fifth pulse counter and to the single input of the third trigger, the output of the fifth pulse counter, which is the second output of the mode control block transformer overload, connected to the third input of co0

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ABOUT

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the corresponding four-input OR element and to the single input of the fourth trigger, the single output of which is connected to the first input of the fifth AND element, the output of the third pulse counter is connected to its reset input, to the reset input of the fifth pulse counter, to the input of the second time delay element, to the input sixth pulse counter, to the first input of the sixth element And and to the second input of the fifth element And, whose output, which is the third output of the transformer overload control unit, is connected to the second input, respectively of a two-input OR element and to the zero input of the fourth trigger, the output of the second time delay element is connected to the zero input of the third trigger, the zero output of which is connected to the second input of the sixth AND element, and the single output is connected to the enable input of the sixth pulse counter, the output of which is the fourth output of the transformer overload control unit is connected to the fourth input of the corresponding four-input OR element and to the first input of the second OR element, the second input of which connected to the output of the sixth; - And element, and the output to the reset input of the sixth counter, and to the zero input of the first trigger.

Fig. 1 is a block diagram of an apparatus; figure 2 is a graph of the load of the substation and diagrams of power transformers, figure Fig. 3 - diagrams of the input signals of the functional blocks of the device.

Figure 1 presents a schematic diagram of a transformer substation with an indication of the secondary circuits of current and voltage transformers, as well as a functional diagram of a device that includes energy meters 1 and 2 with pulse sensors, pulse counters 3, 28, 30, 41, 44, 45, 48, triggers 4-8, 34, 35, 38, 47, logical elements NOT 9, AND 10, 11, 26,33, 36, 40, 42, 49 and OR 18-21, 27, 50, execution unit 12, cycle sensor 13, switching unit 14, source for setting the initial state 15, transformers of the substation 16, 17, control units for overload conditions of transformers 22, 2 3. Zero organs 24, 25, 43, pre10

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current / frequency generator 29, storage register 31 adder 32, timer 37, time delay elements 39, 46,

Figure 2 presents the graph of the load of the substation (5 g), the line of the mode of minimum losses (Sa), the line of overload modes (50), the moments of switching transformers (t) and diagrams of the operation of power transformers 1b, 17.

For the switching unit 14, the states corresponding to the connection of the first (1X) and second (2X) energy meters to the pulse counter -f5 and disconnection of the power transformers sov. 3.16 and 17 under load are indicated.

Fig. 3 shows diagrams. The cycle master 13 controls the operation signals of blocks 6-8, 10-12, the elements 3, 4, 5, 10 and 11. 21, 25, 28, 43.

Energy meters 1 and 2 convert the input values of the load current of transformers 16 and 17 and the voltage of the substation using pulse sensors in a pulse sequence. The number of pulses generated by 25 sensors in a given time is proportional to the load on the transformer.

The pulse counter 3 has a counting and zero inputs and two outputs. A sensor 30 output is connected to the counting input.

energy meter 1 (2), zero input Switching unit 14 is designed to return the meter to its original state. At the first exit, an impulse appears when reaching

signal equal to unity at zero potential at the input, and vice versa.

Logic elements I 10 and 11, 26, 33, 36, 40, 42, 49 generate a signal at the output equal to unity while there are unit potentials at all inputs, and the signal is equal to zero in all other cases.

The Executive unit 12 is designed to convert the input control signals into commands Enable and Disable, which are respectively included

Triggers 6 and 7 are designed for 20 distributing the Turn On and Off signals alternately to the switch of power transformers 16 and 17, three ger 6 through elements OR 18, 19, and trigger 7 through elements OR 20, 21.

When a signal arrives at the counting input of the trigger, a pulse appears at each of its two outputs, which is converted by the executive unit 12 to correspond to the power transformer that remains 35- in operation after the next command Disconnect is connected to the energy meter. This block can be made in the form of a trigger, the counting input of which is connected to the output of the logical element And 11 in the channel

the number of input pulses of the quantity corresponding to the power S,. ,, i.e. power corresponding to the mode of minimum losses.

At the second output of counter 3, by v0

5 and disconnecting power transformers 16 and 17 under load.

signal equal to unity at zero potential at the input, and vice versa.

Logic elements I 10 and 11, 26, 33, 36, 40, 42, 49 generate a signal at the output equal to unity while there are unit potentials at all inputs, and the signal is equal to zero in all other cases.

The Executive unit 12 is designed to convert the input control signals into commands Enable and Disable, which are respectively included

The cycle master 13 controls the operation of elements 3, 4, 5, 10 and 11.

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30 SHCHU command.

Triggers 6 and 7 are designed for 0 distribution of Turn On and Off signals alternately to the switches of power transformers 16 and 17, trigger 6 through OR elements 18, 19, and trigger 7 through OR elements 20, 21.

When a trigger signal arrives at the counting input, a pulse appears at each of its two outputs, which is converted by the executive unit 12 to the corresponding one. Switching unit 14 is designed

to connect to the energy output meter of the power transformer that remains in operation after the execution of the next Disconnect command. This block can be made in the form of a trigger, the counting input of which is connected to the output of the logical element And 11 in the channel

a pulse is generated when the number of disconnections of the power transformer is reached,

input pulses of the quantity corresponding to Sq / 2, i.e. power coming to one transformer with two transformers switched on when the substation load corresponding to the minimum loss mode.

Triggers 4 and 5 are designed to fix the output pulses generated by the counter 2. The pulses from the outputs of the counter 3 are supplied to the unit inputs, and an output signal is generated at the output of the trigger. The trigger zero input is designed to return it to its original (zero) state.

Logic element NOT 9 performs a logical negation operation by generating output

and an actuator, for example, a two-position relay, which connects the output of the corresponding energy meter to the input of the measurement unit, is connected to the trigger output. The zero input of block 14 serves to reset the block to its initial state.

Zero inputs of elements 6, 7, 8

and 14 are connected to the source of the initialization signal through the button 15, by pressing which the device is restored to its initial state.

Trigger 8 is designed to prevent false alarms of the device when the load of one power transformer is less than Sa / 2 with one transformer turned on and the load

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more than Sq with two transformers switched on.

Logic gates OR 18-21, 27, 50 generate a single signal at the output in the presence of at least one of the inputs of unit potentials and a zero signal in their absence.

The control units for the overload conditions of transformers 22, 23 generate single signals at the outputs and, accordingly, through the elements OR 18-21 they act on the executive unit 12, which outputs signals to turn on / off transformers 16, 17 or turn off both at once with a time delay inversely proportional to the time disconnecting the overload current of operating transformers.

The zero-organs 2k, 25, k3 produce a single signal at the output when the input signal coming from transformer substations exceeds the internal reference signal corresponding to current overload: 1, k. n - for block 2kJ 1,3 IH - for block 25, 1,0 1c - for block k3,

Pulse counters 28, 30, k, kk kSt 8 have an input for counting a pulse sequence, a n-bit parallel output in the binary code of the counted pulses, allowing the input at a unit potential at which a pulse sequence can be input, and a reset input that sets the pulse counters to the zero state of their output registers. The counter 28 when reading the number of pulses proportional to the load of the transformer in current and unit potential at the enable input, at one of the outputs generates a single signal to turn off the overloaded transformer. Counter 30 calculates the average load factor of the transformer per day and is connected to the storage register 31 by an n-bit output. Counter H counts n pulses and is used to control the shift of information in the storage register by n bits. Counters kkt 5 | 8 count 2k hours, 6 hours and 5 days, respectively, and when filling in with data values of their internal jserw77200

At the output, a single signal is generated.

The current-frequency converter 29 converts the current supplied to its input into rectangular pulses of the same amplitude at the output, the frequency of which is directly proportional to the value of the current at the input, i.e.

.Q of the current transformer load.

The storage register 31 every hour records information from the pulse counter 30 about the loading of the current transformer 15, having previously shifted the previous information. The storage register is n-bit, where the number of bits is determined by the control accuracy, has a depth of 2k write cycles, and when 25 values are written, 1 value is erased and so on. Thus, the storage register matters about the load factor of the previous day. The adder 32 has

25 input 2k p-bit which receives from the storage register information about the load factor in every hour for the previous day. Only after summing and obtaining the value

30 of an average load factor of less than 0.93, a single potential is generated at its output.

Triggers 3k, 35, 38, kl have zero and single inputs and outputs. With a positive pulse at one of the inputs, a single value is set at the corresponding output, and a value of zero at the other output, and this state of the trigger does not change from until a positive pulse arrives at the other of the inputs of the trigger. At the moment of power-up by means of integrating circuits, all these triggers are installed at the zero output

45 to a single value.

The timer 37 generates hour, minute and second pulses to control the operation of the elements of the transformer overload control unit

0 current.

The time delay elements 39, 6 delay the output pulse in time relative to the input.

The device works as follows about 5 times. Two transformers 16 and 17 are installed at the two-transformer substation. The load of the substation is changed according to the schedule in Fig. 2. The first is transform 5

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torus 16. After supplying voltage to the device at time tQ by pressing button 15, the zero inputs of elements 6, 7, I and 8 are supplied. the signal that brings these element to the zero state, which corresponds to the presence of a unit voltage at the first output of element 6 (Enable 16), and accordingly, at the output of element OR 18, at the second output of element 7 (Disable 17) and, accordingly, at the output of the element OR 21 at the first output of element 8 and connects, by unit 1, the output of energy meter 1 to the pulse counter 3. There is no signal at the second output of elements 6 (Enable 17), 8 and the first output of element 7 (Disable 16). Therefore, the executive unit 12 generates commands to turn on the transformer 16 and turn off the transformer 17.

Since in the time interval t0 - t the load of the transformer 16 is within Sa, the control signal appears only at the output ХЗ (2) of the measuring unit, which brings the trigger 5 to a single state. The element NOT 9 supplies a zero signal to one of the input of the element And 11, which does not cause any changes in the state of the elements 11, 8, 10, 6, 7, 1, and 12.

At time t (when the load of transformer 16 becomes, there will also be no signal at the second output ХЗ (2) of pulse counter 3, which brings trigger 5 to the zero state, and a single CHI channel appears at the output of element 9; which goes to the input of element 11, the second input of which receives a signal from the setter 13, but since the signal X8 (2) 0 arrives at the third input of element 11 through trigger 8, there is no change in the state of element 11 and there are no switching in the circuit will be.

In the time interval, the operation of the circuit does not change compared to the operation at time t0.

The operation of the circuit in the time interval is similar to the operation at time t0.

At time t3, the load of the transformer becomes equal to Sa and a signal appears on the first output of pulse counter 3 ХЗ (1), which

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sets trigger k to a single state. The signal from the trigger output goes to the input of the logical element And 10,

The second input receives a signal from the setter 13 and the third input receives a signal from the first output of trigger 8 X8 (1), which brings the logic element 10 to a single state. Trigger 6 will change its state: a unit potential appears at the second output X8 (2) (Turn on 17) and, accordingly, at the output of the OR element 19, and at the first output the signal will be zero.

Trigger 7 will not change its state. The signal from the output of element 10 goes to the single input of trigger 8 and puts it into a single state, which corresponds to a unit potential at the second output X8 (2) and zero at the first. The switching unit 1) does not change its state 5 nits. The Executive unit 12 upon receipt of the signal Xb (2) through the element OR 19 will be formed the command Enable 17i

Transformer 17 will be turned on under load. Both transformers are in operation for a period of time. The load of the substation does not exceed

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2S0, i.e. for each transformer

load comes

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Sq

S Sa / 2 and

the operation of the circuit is similar to work in the period t0-t {or.

At time tq. the load of the substation is reduced to Sq, i.e. one transformer has an Sq / 2 load. The signal will not appear on any of the outputs of the pulse counter 3 As a result, the signal from element 9 is supplied to the first input of element 11, to the second input from setter 13, and to the third from the second output of trigger 8.

As a result, an impulse appears at the output of element 11, which will change the state of trigger 7, i.e. A single signal appears at the first output of the trigger, and a zero signal at the second. The trigger 6 does not change its state. The signal from the output of element 11 goes to the zero input of trigger 8 and brings it into a state corresponding to the unit potential at the first output X8 (1) and zero at the second output X8 (2).

The switching unit 14 changes its state by connecting the output of the second energy meter 2 to the input of the pulse counter 3 and disabling the output of the energy meter 1. The executive unit 12, when the signal X7 (1) is received via the OR element 20, the command Shutdown 16 will be generated. Transformer 16 will disconnected.

A transformer 17 is in operation at time interval t4-t. The operation of the device is similar to operation at time interval t2-tj.

At time ts, the operation of the circuit is similar to operation at time t3 with the difference that a transformer 16 is connected to the load. If the transformer 16 does not switch for some reason and the load exceeds the value of Sn, then after a time delay dependent on the current overload, the trip transformer 17.

At time t6, the load of the substation exceeds 2Sq, and the load of one transformer exceeds S. At the first output of the pulse counter 3, a pulse appears that brings the trigger 4 to a single state, and a signal is sent to the first input of element 10. The second input of the element receives a signal from the setter 13, but since the signal will not be supplied to the third input, there will be no signal at the output of the element 10. Therefore, at time interval t6-t7, the state circuit does not change.

This state of the circuit will be preserved.

until the time tg, when the load of the substation is reduced to S0. At this moment, the operation of the circuit is similar to operation at time t and with the difference that the transformer 17 will be turned off and the output of the first energy counter 1 will be connected to the pulse counter 3.

In the time interval tg-tg, the circuit works in exactly the same way as in

te-t

ta-t3,

. The moment of time C fully corresponds to the moment of c.

In the time interval, the operation of the circuit is similar to its work in the time interval.

At the time point, the load of the substation exceeds 2Sn, and the load of one transformer exceeds Sn. Thus both

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control unit of transformer overload modes 22, 23. Since the operation of both units is similar, we describe the operation of one of them.

At the moment of time, the null-organ 43 is triggered and at its output a unit potential is established, which enters the input of the And element 42, thereby allowing the passage of minute impulses to its output. The trigger 47 is set to a single state, allowing its single output to pass the daily pulses to the input of the pulse counter 48. Through the And 33 element, provided that there is a unit potential at its first input, which would correspond to a current transformer load factor of less than 0.93 1H , the minute pulse switches the trigger 34 to a single state, allowing the arrival of minute pulses to the pulse counter 44, Minute pulses are also sent to the α-counter 4. pulses 45. At time t, the overload of the current transformers exceeded 1.3 1N and the zero-organ 25 worked and if the trigger 34 had not been switched before, and this would have happened if the output of the adder 32 had a logical zero, when the load factor 0.93j is exceeded, then through the AND 26 and OR 27 elements, an enable signal would arrive at the pulse counter 28 and, after a time delay, would turn off the overloaded transformer. At a point in time.

the current transformer overload exceeded 1.4 1c and the zero-organ 24 tripped. Through the OR element, the enable signal enters the pulse counter 28 and the counter, receiving pulses from the current / frequency converter through a time delay depending on the overload factor, turns off the overloaded transformer in moment of time If the value of the overload coefficient did not exceed 1.4 1N and under the condition of a load factor not exceeding 0.93 IH Th ° considered above, then the pulse counter 45 after

counting six hours of total work during the day with an overload in the range of 1.0 IH - 1.4 1c disconnects the overloaded transformer through the OR 20 element and sets

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trigger single output 35 to a single state. After 2k hours, the output of the pulse counter 44 sets the value of the logical unit, which is fed to the input of the pulse counter 4P, to its reset input, to the reset of the pulse counter 45 and through the time delay element 46 to the zero input of the trigger 47, as well as to the second input of the element And 36, If the transformer over the past day worked with an overload in the range of 1.0 T c - 1.4 "for more than 6 hours and it was turned off at the output of the pulse counter 45, then trigger 35 with a single output would allow the passage of the pulse from the counter 4 4 across AND element 36 and OR element 18 to turn on the transformer; v setting the trigger output of the trigger 35 to zero. And if the transformer with this overload would work for less than 6 hours, then no signal to turn on would pass. If over the next day there would be an excess of the current load of the controlled transformer to 1H, then the null-organ 43 would work again and the operation of the circuit would be repeated according to the algorithm described above. The touch circuit works for 5 days, after which the value of the logical unit would be established at the output of the pulse counter 48, which would turn off the overloaded transformer through the OR element 20 and reset the pulse counter 48 through the OR element 50 and set the zero output of the trigger 34 to a single state. If within 5 days from the beginning of the determination of current overload above 1 N, on any day the value of 1 N would not exceed the current, then during these days at the zero output of trigger 4 the logical unit value would not change and then the pulse coming from pulse counter 44 through element AND 49 and element OR 50 would reset the value of pulse counter 48 and set the zero output of trigger 34 to a single state, i.e., would return the circuit to its original mode.

The current / frequency converter 29 is constantly connected to the load current of the transformer and changes the output frequency in direct proportion to the value of 77200

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input current. The pulse counter 30 digitally measures the load factor of the transformer every hour by counting the pulses coming from the output of the current / / frequency converter. 1 hour after turning on the current transformer overload control unit, an hourly pulse,

p coming from the timer 37. sets the single output of the trigger 38 to the single state, and then the first n-second pulses, where the number p is equal to the number of output bits of the pulse counter 30 and the input bits of the storage register 31, through the And 40 element the digital value of the load factor as if deep into the storage register 31. By

At the end of the shift of all the registers at the output of the pulse counter 41, a single potential is generated, which resets the pulse counter 41 and sets the logic zero to a single output 5 of trigger 3 $, prohibiting the further passage of second pulses through the And 40 element, and the value at the zero output of trigger 38 will be set to a logical unit that will record the information of the digital value of the load factor for the last hour in the upper freed storage register 31 and after a short delay and in block 39 it will reset the pulse counter 30 to the zero state, thereby preparing it for a new account, 24 kn-bit information from the storage register 31 is fed to

Q adder 32, which sums up 24 previous digital values of load factors for each hour and when the average load factor exceeds the value corresponding to

, 0.93 1n1 at the output of the adder 32, a logical zero value is set, blocking through the element And 33 the operation of the transformer overload control circuit for 5 days

n for 6 hours with a value of the overload coefficient not exceeding 1.4 1N, provided that the average value of the load factor for the previous days is more than 0.93 ".

Thus, triggers 6 and 7 provide alternate switching on and off of power transformers, which provides approximately equal time

m of transformer operation under load and the same number of on-off operations of each transformer. Trigger 8 ensures the correct operation of the device with substation loads less than Sa / 2 and more than 2sa. The units for monitoring the overload conditions of transformers of a two-transformer substation control the shutdown of transformers with time delays not exceeding the requirements of the technical operation rules and GOST for various current transformer overload factors.

Claims (1)

The claims A device for automatically controlling the number of parallel-running power transformers of a two-transformer substation, containing two energy meters with a pulse sensor and inputs for connecting to the voltage of the substation and the load current of the transformers connected to the pulse counter via a switching unit, and two outputs of the pulse counter are connected to single inputs triggers, the output of the first ger directly, and the second through the logic element is NOT connected to the first inputs of the logical elements AND, the outputs of the cat The first ones are connected to the counting inputs of the third and fourth triggers, while the zero inputs of the pulse counter and the first two triggers and the second inputs of the logical elements AND are connected to the outputs of the loop master, and the zero inputs of the third, fourth and fifth triggers and the switching block are connected to the source the initialization signal, the single and zero inputs of the fifth trigger are connected to the outputs of the logical elements AND, and its outputs are connected to the third inputs of the logical elements AND, and the control input of the block is switched connected to the output of the AND gate in a channel interrupting the power transformer, the actuating unit, characterized in that, in order to increase the reliability by controlling the mode transformer substation overload current, it is further provided with two elements of the two-input OR chetyrehvhodovymi two OR elements and two control units 0 5 0 5 0 5 0 5 0 5 transformer overload modes, the outputs of the four OR elements connected to the executive unit, and the first inputs of the two-input OR elements connected respectively to the single and zero outputs of the third trigger, and the second inputs of the first two OR elements connected to the fourth outputs of the respective transformer overload control units, the first inputs two four-input OR elements are connected respectively to the zero and single outputs of the fourth trigger, and the second, third and fourth inputs are Three-input OR elements are connected to the first three outputs of the corresponding current-mode transformer overload transformer overload control units, each of which contains three zero-elements, a timer, six two-input AND elements, two two-input OR elements, four triggers, a current-frequency converter, two delay elements time, six pulse counters with enable inputs for counting and reset, an adder and a storage register with inputs for recording information and shift, with all zero-organs and a current-frequency converter connected to the input to current load transformers, the output of the first zero-organ is connected through the first input of the first OR element to the enable input of the first pulse counter, the output of the second zero-organ is connected to the first input of the first AND element, the output of which is connected to the second input of the first OR element, and the output the current-frequency converter is connected to the inputs of the first and second pulse counters, the output of the first pulse counter, which is the first output of the transformer overload control unit, is connected to the second input, respectively of the existing four-input OR element, and the output of the second pulse counter is connected to the input of the storage register, the output of which is connected to the adder connected to the first input of the second AND element, whose output is connected to the unit input of the first trigger, the zero output of which is connected to the second input of the first, element And, and a single output is connected to the enable input of the third counter impotite fa t ts tet-j te te tiotiitiatta Figure 2.