CN117040095B

CN117040095B - Spare power automatic switching method for five-way incoming line of 10kV three-section bus of station service

Info

Publication number: CN117040095B
Application number: CN202310828079.6A
Authority: CN
Inventors: 罗金嵩; 吴礼贵; 李琛; 吴修韩
Original assignee: China Yangtze Power Co Ltd
Current assignee: China Yangtze Power Co Ltd
Priority date: 2023-07-06
Filing date: 2023-07-06
Publication date: 2024-10-01
Anticipated expiration: 2043-07-06
Also published as: CN117040095A

Abstract

The automatic switching method comprises the steps that a standby power automatic switching method for five incoming lines of a 10kV three-section bus for factory use is adopted, an incoming line 1 is connected with a bus I through a circuit breaker 2DL, and a power supply 1B is connected with the bus I through a circuit breaker 1 DL; the power supply 2B is connected with a bus II through a breaker 6 DL; the incoming line 2 is connected with a bus III through a circuit breaker 5DL, and the power supply 3B is connected with the bus III through a circuit breaker 7 DL; the bus I is connected with the bus II through the breaker 3DL, and the bus II is connected with the bus III through the breaker 4 DL. For the bus I, the power supply 1B is a main power supply of the bus, the power supply 2B is an in-plant standby power supply, and the incoming line 1 is an out-plant standby power supply; for the bus II, the power supply 2B is a main power supply of the bus, the power supplies 1B and 3B are standby power supplies in a factory, and the incoming lines 1 and 2 are standby power supplies outside the factory; for the bus III, the power supply 3B is the main power supply of the bus, the power supply 2B is the in-plant standby power supply, and the incoming line 2 is the out-plant standby power supply. The method of the invention realizes the self-adaptive action of the backup power automatic switching under various possible outgoing line operation modes, so that the non-fault voltage-loss bus can be powered back in a short time.

Description

Spare power automatic switching method for five-way incoming line of 10kV three-section bus of station service

Technical Field

The invention relates to the technical field of automatic switching control of a station power system, in particular to an automatic switching method for a station power 10kV three-section bus five-way incoming line.

Background

The Automatic backup power switching device is called as a Automatic backup power switching device Busbar TRANSFER SWITCH (BATS), and can restore power supply for a non-fault power failure area in the shortest time when a power failure accident occurs to the system. When the automatic backup power switch is in operation, the accident range is probably expanded if the automatic backup power switch is in operation after the system is in failure. Each power plant as a system power supply has a high requirement for the power supply reliability of a station power system, and often adopts a redundant configuration of multiple standby power supplies. When the generator stops and exits from running, normal operation is switched off or a fault trips, the standby power is automatically switched on through the standby automatic switching device.

Generally, a spare power automatic switching non-fixed control mode of a factory power system needs to be set according to the configuration condition of on-site primary equipment. The whole wiring form of the station power system is changeable, each power station is different, and the wiring can be changed according to the needs during operation. The charging and discharging, locking logic and action strategy of the spare power automatic switching are often formulated according to the requirements of primary wiring and operation and maintenance. The spare power automatic switching device of domestic manufacturers often adopts a program curing mode, and the spare power automatic switching logic cannot be modified independently. The spare power automatic switching device of foreign manufacturers often uses programmable program blocks as a framework, adopts a virtual logic programming mode, has a certain self-defining function, can adapt to some small system function changes, but needs to reprogram when the wiring of a large system is changed and the operation mode of the system is changed, and meanwhile, flexible and variable programs have high requirements on operation and maintenance personnel. The large power plant often has a plurality of station service power supply points, and under the traditional spare power automatic switching mode, a plurality of sections of buses in each power supply point jointly form an independent on-site spare power automatic switching system, and various details of the spare power automatic switching modes of different power supply points are different, but are mainly classified into the following categories. The existing strategy for the power plant spare power automatic switching is mainly a standard symmetrical double-bus spare power automatic switching logic strategy.

(1) Bus-tie spare power automatic switching:

the bus-tie automatic switching is shown in fig. 2, and the automatic switching device is arranged on the bus-tie switch to realize the function that the bus 1 and the bus 2 are standby power sources. If the 1 master is out of voltage, the 1 master load is transferred to the 2 master through closing the master-to-master switch. When the main power supply is restored to normal, the load can be transferred from 2 to 1.

(2) Single-section bus spare power automatic switching device:

the single-section bus spare power automatic switching device is shown in fig. 3, the spare power automatic switching device is arranged at the switch 1 or 2, and the incoming lines 1 and 2 are mutually standby power supplies. And if the bus is out of voltage, the load of the incoming line 1 is transferred to the incoming line 2 through a switch of the incoming line 2. When the main power supply is restored, the load is transferred from 2 paths back to 1 path.

(3) Combined spare power automatic switching device

The combined automatic bus switching is shown in fig. 4, and has a combined action mode of double-section bus automatic bus switching and single-section bus automatic bus switching, and can be switched to a single-section bus automatic bus switching mode; and the method can also be switched to a double-section bus-tie automatic switching mode to realize combined action logic, and the standby switching sequence is determined according to specific conditions.

The disadvantages of the prior art are:

The power plant system uses a REF-542 device of an ABB company, can be flexibly programmed, is not a special automatic backup switching device, is logically distributed in 7 switch protection devices related to the automatic backup switching, has certain time sequence and logic problems in cooperation, and has the risk of refusal. The main problems are as follows:

(1) Reliability is reduced: flexible logic is adopted, action behaviors are not fixed, the logic is complex, sampling points are more, the action reliability is reduced, and the backup automatic switching action is not synchronous switching.

(2) The time sequence matching difficulty is high: the distributed logic is formed, 7 auxiliary power automatic switching devices of one power supply point all comprise auxiliary power automatic switching programs and cannot be replaced, and the time coordination of the devices is easy to be problematic due to a distributed programming mode, so that action failure is caused.

(3) Program mismatch after optimizing the power plant operation mode: because the GCB is additionally arranged in a certain power plant, the power plant operation mode is greatly optimized, and the main transformer reverse hanging operation mode is adopted, even if the unit is stopped in the dead water period, the main transformer can still operate with the power plant bus, and the mode design of the dead water period and the rich water period in the original automatic switching logic is outdated.

(4) The protection and spare power automatic switching sharing device has safety risk: main inlet wire protection and spare power automatic switching sharing device can influence the spare power automatic switching system when main inlet wire protection device overhauls, has increased the risk of system operation.

In addition, the three-section bus is different from the standard double-bus spare power automatic switching, the three-section bus is asymmetric in wiring, the number of incoming wires is large, the action logic of each section bus is different (the mirror symmetry buses are identical), and the function cannot be realized by using standard control logic similar to the double-bus spare power automatic switching.

Disclosure of Invention

In order to solve the technical problems, the invention provides a spare power automatic switching method for five-way incoming lines of a 10kV three-section bus of a station power supply, which is based on the configuration of a 10kV station power system of a power plant, designs the logic of the three-section station power automatic switching system with five-way incoming line power supply, and realizes the self-adaptive action of the spare power automatic switching under various possible outgoing line running modes, so that a non-fault voltage-losing bus can be powered again in a short time.

The technical scheme adopted by the invention is as follows:

10kV power plant 10kV three-section five-inlet-wire primary system comprises:

Bus I, bus II, bus III, power supply 1B, power supply 2B, power supply 3B, incoming line 1, incoming line 2;

the incoming line 1 is connected with a bus I through a circuit breaker 2DL, and the power supply 1B is connected with the bus I through the circuit breaker 1 DL;

the power supply 2B is connected with a bus II through a breaker 6 DL;

the incoming line 2 is connected with a bus III through a circuit breaker 5DL, and the power supply 3B is connected with the bus III through a circuit breaker 7 DL;

The bus I is connected with the bus II through the breaker 3DL, and the bus II is connected with the bus III through the breaker 4 DL.

For the bus I, the power supply 1B is a main power supply of the bus, the power supply 2B is an in-plant standby power supply, and the incoming line 1 is an out-plant standby power supply;

For the bus II, the power supply 2B is the main power supply of the bus, the power supplies 1B and 3B are standby power supplies in a factory, and the incoming lines 1 and 2 are standby power supplies outside the factory.

In the water-rich period mode, if the main power supply of the bus I disappears, the breaker 3DL is preferably switched on;

in the dry-off period mode, if the main power supply of the bus I disappears, the breaker 2DL is preferably switched on;

under the condition that the breaker 2DL is provided with a bus I, if the bus I has no fault and no voltage is lost, the breaker 3DL is thrown;

in the case where the breaker 3DL has the bus i, if the bus i is not out of voltage due to a fault, the breaker 2DL is put on.

The bus I standby power automatic switching method specifically comprises the following steps:

1) When the bus I fails, the bus I-bus II is connected with the off-site power supply 2 paths of standby power supply, and if the bus II and the bus III run in a separated mode, the first standby is a bus-connected breaker 3DL, and the second standby is an off-site power breaker 2DL; if the bus II and the bus III are in communication operation, the first backup is the off-site power circuit breaker 2DL, and the second backup is the bus-tie circuit breaker 3DL; in this case, a third-band will appear after the second standby operation is successful, and the mode should be switched in time.

2) When the bus I is powered by the main power supply and runs with the bus II, 2 paths of standby power are provided for the off-site power circuit breaker 2DL and the bus-tie circuit breaker 4DL, wherein the standby power is the off-site power circuit breaker 2DL, and the standby power is the bus-tie circuit breaker 4DL; a third switch occurs after the second standby operation is successful, and the operation mode needs to be switched in time.

3) When the main incoming line of the bus I stops, the bus I is powered by the off-site power circuit breaker 2DL, and the bus I and the bus II run in a separated mode, only the bus-tie circuit breaker 3DL is used as a standby power supply.

4) When the main incoming line of the bus I stops running, the bus I is powered by the off-site power circuit breaker 2DL, and the bus I and the bus II operate together, only the bus-tie circuit breaker 4DL is used as a standby power supply; after the action, the bus III is in a third zone, and the mode is required to be switched in time after the action;

5) When the main incoming line of the bus I stops running, the bus I is powered by the bus II, and the bus II is powered by the main power supply, the off-site power circuit breaker 2DL is used as a standby power supply; at this time, bus I the pressure loss needs to be divided into the following cases: if the main power supply of the bus II loses voltage to cause the voltage loss of the bus I, the bus II performs automatic switching action; if the bus-bar circuit breaker 3DL is in a trip, the bus I is provided with a spare power automatic switching action to switch the external power circuit breaker 2DL; if the busbar breaker 3DL is in the protection operation, the busbar I may be failed, so the automatic switching is blocked.

The bus II spare power automatic switching method specifically comprises the following steps:

① : when the bus II is powered by the main power supply and runs in a row, 2 paths of standby power sources are provided for the bus-tie circuit breaker 3DL and the bus-tie circuit breaker 4DL, wherein one standby is the bus-tie circuit breaker 3DL and the other standby is the bus-tie circuit breaker 4DL;

② : when the bus II is powered by the main power supply and operates with the bus I, 2 paths of standby power are provided for the bus I outside plant power circuit breaker 2DL and the bus-tie circuit breaker 4DL, wherein the standby power is provided for the bus I outside plant power circuit breaker 2DL and the standby power is provided for the bus-tie circuit breaker 4DL; a third zone appears after the second standby action is successful, and the operation mode needs to be switched in time;

③ : when the bus II is powered by the main power supply and operates with the bus III, 2 paths of standby power are provided for the bus III external power circuit breaker 5DL and the bus-tie circuit breaker 3DL, one is provided for the bus III external power circuit breaker 5DL, the other is provided for the bus-tie circuit breaker 3DL, and a third strip can appear after the second standby action is successful, and the operation mode needs to be switched in time.

④ : When the main incoming line of the bus II stops running, the bus II is powered by the bus I, and the bus I is powered by a main power supply or an off-site power supply, the bus-connected breaker 4DL is used as a standby power supply; at this time, bus II the pressure loss needs to be divided into the following cases: if the incoming line power supply of the bus I loses voltage, the bus I is used for automatic switching; if the bus-tie breaker 3DL is stolen, the bus II is provided with a spare power automatic switching action to switch the bus-tie breaker 4DL; if the busbar breaker 3DL protection action is performed, the automatic switching equipment is locked because the busbar II is possibly in fault;

⑤ : when the main incoming line of the bus II stops running, the bus II is powered by the bus III, and the bus III is powered by the main power supply or the off-site power supply, the bus-connected breaker 3DL is used as a standby power supply, and the voltage loss of the bus II needs to be divided at the moment: if the incoming power supply of the bus III is in voltage loss, the bus III is used for automatic switching; if the master-link circuit breaker 4DL is stolen, the master-link circuit breaker 2DL is put into action; if the busbar breaker 4DL is in the protection operation, the automatic switching is blocked because the busbar II may be in fault.

The bus III spare power automatic switching method specifically comprises the following steps:

1) When the bus III main power supply fails, a bus III-bus II bus and an off-site power supply 2-way standby power supply exist, and if the bus II and the bus I run in a split mode, the first standby is a bus-connected breaker 4DL and the second standby is an off-site power supply breaker 5DL; if the bus II and the bus III are in communication operation, the first backup is an off-site power circuit breaker 5DL, and the second backup is a bus-tie circuit breaker 4DL; in this case, a third-band will appear after the second standby operation is successful, and the mode should be switched in time.

2) When the bus III is powered by a main power supply and the bus III runs with the bus II, 2 paths of standby power are provided for the off-site power circuit breaker 5DL and the bus-tie circuit breaker 3DL, wherein the standby power is the off-site power circuit breaker 5DL, and the standby power is the bus-tie circuit breaker 3DL; a third switch occurs after the second standby operation is successful, and the operation mode needs to be switched in time.

3) When the main line of the bus III is stopped, the bus III is powered by the off-site power circuit breaker 5DL, and the bus III and the bus II are operated in a separated mode, only the bus-tie circuit breaker 4DL is used as a standby power supply.

4) When the main incoming line of the bus III is stopped, the bus III is powered by the off-site power circuit breaker 5DL, and the bus III and the bus II are combined for bus operation, only the bus-connected circuit breaker 3DL is used as a standby power supply; the bus I is provided with a third section after the action, and the mode is required to be switched in time after the action;

5) When the main incoming line of the bus III is stopped, the bus III is powered by the bus II, and the bus II is powered by the main power supply, the off-site power circuit breaker 2DL is used as a standby power supply; at this time, bus I the pressure loss needs to be divided into the following cases: if the main power supply of the bus II loses voltage to cause the voltage loss of the bus III, the bus II performs automatic switching action; if the bus-bar circuit breaker 4DL is stolen, the bus III is automatically switched on the external power circuit breaker 5DL; if the busbar breaker 4DL is in the protection operation, the busbar iii may be in failure, and thus the automatic backup switch is locked.

The invention discloses a spare power automatic switching method for five-way incoming lines of a 10kV three-section bus for station service, which has the following technical effects:

1) The logic adaptability is better: aiming at the atypical three-section five-wire power supply station service electric wiring form, the spare power automatic switching logic design is carried out, the adaptability problem of a program after GCB is additionally installed is solved, and related achievements can be applied to a station service electric system similar to the multi-wire power supply three-section wiring.

2) The operation reliability is improved: in order to avoid program competition and improve the success rate of spare power automatic switching action, an action mode of a strategy table is adopted. In the conventional operation mode, the system has a unique corresponding spare power automatic switching action mode; the logic design in the water-rich period and the water-withered period is canceled, the logic is simple and reliable, and the operation of operators is simple and convenient;

3) Time setting is easier: the centralized control strategy is adopted, the incoming line time of the spare power automatic switching center unit is set, and the other switches are used as executing elements, so that the time coordination of the whole system is easier, and the problem of time mismatch possibly caused by extreme conditions such as low bus voltage attenuation is solved;

4) Each logic detail is more perfect: the analysis of the cases of failure of the old backup automatic switching logic and other power station backup automatic switching actions is carried out, and the targeted optimization is carried out, for example: a. after the automatic spare power switching is started, the original wire inlet switch is required to be tripped in a delayed manner, after the tripping of the circuit breaker is determined, the subsequent logic is executed, and if the position of the switch is not returned, the automatic spare power switching is finished, so that the asynchronous switching-on condition is prevented. b. The thought of the central unit is adopted, and the logic of jumping is designed, so that the problem of program competition possibly existing in the process of combining the mother and the son is solved. c. The switch position contacts are reasonably distributed and used, and the handcart position contacts minimize the influence of position contact errors on the spare power automatic switching action.

5) System maintenance is easier: the special device is adopted to facilitate the maintenance of the automatic spare power switching device, the automatic spare power switching device is concentrated in 3 main incoming line units, other disk cabinets are not involved, the automatic spare power switching operation is not affected by the protection and the shutdown of the incoming line switch, and the program is not required to be modified in the process of program solidification and maintenance.

Drawings

Fig. 1 is a primary wiring diagram of the spare power automatic switching.

Fig. 2 is a bus-tie spare power automatic switching wiring diagram.

Fig. 3 is a single-section bus spare power automatic switching wiring diagram.

Fig. 4 is a combined spare power automatic switching wiring diagram.

Fig. 5 is a schematic diagram of an initial running state of the bus i station power automatic switching mode.

Fig. 6 is a logic diagram of the closing breaker 3DL switch.

Fig. 7 is a logic diagram of the trip breaker 3DL switch.

Fig. 8 is a schematic diagram of a bus I station service power automatic switching mode two initial operation states.

Fig. 9 is a schematic diagram of three initial operation states of the bus I station power automatic switching mode.

Fig. 10 is a schematic diagram of a bus i station power automatic switching mode four initial operation states.

Fig. 11 is a schematic diagram of a five-initial operation state of the bus I station power automatic switching mode.

Fig. 12 is a schematic diagram of an initial operation state of the bus ii station service power automatic switching mode.

Fig. 13 is a schematic diagram of a bus ii station service power automatic switching mode two initial operation states.

Fig. 14 is a schematic diagram of a bus ii station service power automatic switching mode in three initial operating states.

Fig. 15 is a schematic diagram of a bus ii station service power automatic switching mode four initial operation states.

Fig. 16 is a schematic diagram of a fifth initial operation state of the bus ii station service power automatic switching mode.

Detailed Description

Because the 10kV power plant system of a certain power plant is weaker in operation mode in the initial production stage, the 10kV power plant primary system is designed into a three-section wiring mode for ensuring reliability, and meanwhile, in-plant and out-of-plant power supplies are introduced as standby power supplies. Fig. 1 is a primary wiring diagram of a power plant automatic switching, taking a bus i as an example, a power supply 1B is a main power supply of the bus, a power supply 2B is a standby power supply in a plant, and an incoming line 2 is an external standby power supply. Taking a bus II as an example, a power supply 2B is a main power supply of the bus, a power supply 1B and a power supply 3B are stand-by power supplies in a factory, and an incoming line 2 and an incoming line 3 are stand-by power supplies outside the factory. Can be summarized into a five-power three-section wiring form:

a: in the water-rich period mode, if the main power supply of the bus I disappears, the breaker 3DL is preferably switched on; in the mode of the water-rich period, the buses in the plant are all operated in a separated mode, and the standby power supply is preferentially used for the power supply in the plant because the reliability of the power supply in the plant is higher.

B: in the dry-off period mode, if the main power supply of the bus I disappears, the breaker 2DL is preferably switched on; in the dry-off period mode, the bus in the plant is influenced by unit overhaul, so that the bus is in a parallel operation mode with high probability, namely the bus is in a closing operation state.

C: under the condition that the breaker 2DL is provided with a bus I, if the bus I has no fault and no voltage is lost, the breaker 3DL is thrown; only one backup power source of the bus-tie breaker 3DL is provided at this time, and all the backup power sources can only throw 3DL.

D: in the case where the breaker 3DL has the bus i, if the bus i is not out of voltage due to a fault, the breaker 2DL is put on. Only the breaker 2DL is a standby power source at this time, and all can only throw 2DL.

The design of the three-section five-wire spare power automatic switching logic is different from the conventional double-bus spare power automatic switching logic, the complexity of the strategy is greatly increased compared with that of the double-bus spare power automatic switching logic, and the reliability of the strategy action is greatly improved compared with that of the strategy in a distributed mode.

(One): bus I spare power automatic switching logic:

The bus I and the bus III are mirror symmetry in structure, so that the logic is identical, and the definition of numbers of the switches in the program is different. Taking bus I as an example, 5 kinds of backup power automatic switching logics and 2 kinds of self-recovery logics of bus I/bus III are described, and the switch numbers are shown in FIG. 5:

1) In normal operation, the three bus segments are operated in sections and are respectively powered by the main power supply, as shown in fig. 5. When the main power supply of the bus I fails, a bus I-bus II bus and an off-site power supply 2-way standby power supply exist, and if the bus II and the bus III run in a split mode, the first standby is a bus-connected breaker 3DL, and the second standby is an off-site power supply breaker 2DL; if the bus II and the bus III are in communication operation, the first backup is the off-site power circuit breaker 2DL, and the second backup is the bus-tie circuit breaker 3DL; in this case, a third-band will appear after the second standby operation is successful, and the mode should be switched in time.

Taking bus I as an example, the logic mode I of the spare power automatic switching is taken, and the logic block diagram of the closing and tripping circuit breaker 3DL is shown in fig. 6 and 7.

2) When the bus I is powered by the main power supply and the bus I runs with the bus II, 2 paths of standby power are provided for the off-site power circuit breaker 2DL and the bus-tie circuit breaker 4DL, as shown in figure 8. The first is an off-site power circuit breaker 2DL, and the second is a bus-tie circuit breaker 4DL; a third switch occurs after the second standby operation is successful, and the operation mode needs to be switched in time.

3) When the main incoming line of the bus I is stopped, the bus I is powered by the off-line power circuit breaker 2DL, and the bus I and the bus II are operated in a split mode, only the bus-bar circuit breaker 3DL is used as a standby power supply, as shown in fig. 9.

4) When the main line of the bus I is stopped, the bus I is powered by the off-line power breaker 2DL, and the bus I and the bus II are combined to run, the mode is rare, as shown in FIG. 10. Only the busbar breaker 4DL is used as a standby power supply; after the action, the bus III is in a third zone, and the mode is required to be switched in time after the action;

5) When the main incoming line of the bus I is stopped, the bus I is powered by the bus II, and the bus I is powered by the main power supply, the off-site power circuit breaker 2DL is used as a standby power supply, as shown in FIG. 11. At this time, bus I the pressure loss needs to be divided into the following cases: if the main power supply of the bus II loses voltage to cause the voltage loss of the bus I, the bus II performs automatic switching action; if the bus-bar circuit breaker 3DL is in a trip, the bus I is provided with a spare power automatic switching action to switch the external power circuit breaker 2DL; if the busbar breaker 3DL is in the protection operation, the busbar I may be failed, so the automatic switching is blocked.

(II): bus II spare power automatic switching logic:

The following describes 5 kinds of backup power automatic switching logics and 2 kinds of automatic recovery logics of the bus II, and the switch numbers are shown in the following figures 12-16:

① : when the bus II is powered by the main power supply and the bus II operates in a row, 2 paths of standby power sources are provided for the bus-tie circuit breaker 3DL and the bus-tie circuit breaker 4DL, wherein one standby is the bus-tie circuit breaker 3DL and the other standby is the bus-tie circuit breaker 4DL, as shown in figure 12.

② : When the bus II is powered by the main power supply and operates with the bus I, 2 paths of standby power are provided for the bus I outside plant power circuit breaker 2DL and the bus-tie circuit breaker 4DL, namely the bus I outside plant power circuit breaker 2DL and the bus-tie circuit breaker 4DL are provided for the bus II, and the two standby power are shown in fig. 13. A third zone appears after the second standby action is successful, and the operation mode needs to be switched in time;

③ : when the bus II is powered by the main power supply and operates with the bus III, 2 paths of standby power are provided for the bus III external power circuit breaker 5DL and the bus-tie circuit breaker 3DL, namely the bus III external power circuit breaker 5DL and the bus-tie circuit breaker 3DL are provided for one, and the two paths are provided for the other, as shown in fig. 14. A third switch occurs after the second standby operation is successful, and the operation mode needs to be switched in time.

④ : When the main incoming line of the bus II is stopped, the bus II is powered by the bus I, and the bus I is powered by the main power supply or the external power supply, the bus-tie breaker 4DL is used as a standby power supply, as shown in fig. 15. At this time, bus II the pressure loss needs to be divided into the following cases: if the incoming line power supply of the bus I loses voltage, the bus I is used for automatic switching; if the bus-tie breaker 3DL is stolen, the bus II is provided with a spare power automatic switching action to switch the bus-tie breaker 4DL; if the busbar breaker 3DL protection action is performed, the automatic switching equipment is locked because the busbar II is possibly in fault;

⑤ : when the main line of the bus II is stopped, the bus II is powered by the bus III, and the bus III is powered by the main power supply or the off-site power supply, the bus-tie breaker 3DL is used as a standby power supply, as shown in FIG. 16. At this time, bus II the pressure loss needs to be divided into the following cases: if the incoming power supply of the bus III is in voltage loss, the bus III is used for automatic switching; if the master-link circuit breaker 4DL is stolen, the master-link circuit breaker 2DL is put into action; if the busbar breaker 4DL is in the protection operation, the automatic switching is blocked because the busbar II may be in fault.

The invention reconstructs the power plant automatic switching logic of the 10kV power supply point, designs and researches the automatic switching action mode, solves the problems existing in the old mode, and adapts to the new system operation mode. The new spare power automatic switching device can be well adapted to the existing operation mode, and the new logic is simple and clear compared with the old logic, and has the following characteristics:

(1) Action logic solidifies and the program is not modifiable. The station domains with different wiring modes are designed with spare power automatic switching of different logics, and the probability of manual setting by mistake is reduced by logic solidification.

(2) The centralized action logic mode is that the spare power automatic switching device is a logic judgment control unit, and the rest protection devices are execution units, so that the circuit wiring is simplified.

(3) After the power operation mode of the plant is optimized, the bus is supplied with power by a main power supply source in most cases, so that the modes of dead water and rich water are canceled, only one action mode is reserved, and the standby automatic switching action logic is executed in a table look-up mode according to the positions of the switch and the handcart and the voltage analog quantity.

(4) The special spare power automatic switching device is arranged, and each bus is provided with one spare power automatic switching device according to the difficulty of logic design and maintenance, so that the reliability is improved, and the maintenance is more convenient.

Claims

1. 10KV of station service electricity "three segmentation five inlet wire" primary system, its characterized in that, this system includes:

the power supply 2B is connected with a bus II through a breaker 6 DL;

The bus I is connected with a bus II through a breaker 3DL, and the bus II is connected with a bus III through a breaker 4 DL;

bus I spare power automatic switching method based on the system specifically comprises the following steps:

1) When the bus I fails, the bus I-bus II is connected with the off-site power supply 2 paths of standby power supply, and if the bus II and the bus III run in a separated mode, the first standby is a bus-connected breaker 3DL, and the second standby is an off-site power breaker 2DL; if the bus II and the bus III are in communication operation, the first backup is the off-site power circuit breaker 2DL, and the second backup is the bus-tie circuit breaker 3DL; in this case, a third-band will appear after the second standby action is successful, and the mode should be switched in time;

2) When the bus I is powered by the main power supply and runs with the bus II, 2 paths of standby power are provided for the off-site power circuit breaker 2DL and the bus-tie circuit breaker 4DL, wherein the standby power is the off-site power circuit breaker 2DL, and the standby power is the bus-tie circuit breaker 4DL; a third zone appears after the second standby action is successful, and the operation mode needs to be switched in time;

3) When the main incoming line of the bus I stops, the bus I is powered by the off-line power circuit breaker 2DL, and the bus I and the bus II run in a separated mode, only the bus-connected circuit breaker 3DL is used as a standby power supply;

5) When the main incoming line of the bus I stops running, the bus I is powered by the bus II, and the bus II is powered by the main power supply, the off-site power circuit breaker 2DL is used as a standby power supply; at this time, bus I the pressure loss needs to be divided into the following cases: if the main power supply of the bus II loses voltage to cause the voltage loss of the bus I, the bus II performs automatic switching action; if the bus-bar circuit breaker 3DL is in a trip, the bus I is provided with a spare power automatic switching action to switch the external power circuit breaker 2DL; if the busbar breaker 3DL protection action is performed, the automatic switching equipment is locked because the busbar I is possibly failed;

bus II spare power automatic switching method based on the system specifically comprises the following steps:

③ : when the bus II is powered by the main power supply and operates with the bus III, 2 paths of standby power are provided for the bus III external power circuit breaker 5DL and the bus-tie circuit breaker 3DL, wherein one standby is the bus III external power circuit breaker 5DL and the other standby is the bus-tie circuit breaker 3DL, and a third-band operation occurs after the second standby is successful, and the operation mode needs to be switched in time;

⑤ : when the main incoming line of the bus II stops running, the bus II is powered by the bus III, and the bus III is powered by the main power supply or the off-site power supply, the bus-connected breaker 3DL is used as a standby power supply, and the voltage loss of the bus II needs to be divided at the moment: if the incoming power supply of the bus III is in voltage loss, the bus III is used for automatic switching; if the master-link circuit breaker 4DL is stolen, the master-link circuit breaker 2DL is put into action; if the busbar breaker 4DL protection action is performed, the automatic switching equipment is locked because the busbar II is possibly in fault;

bus III spare power automatic switching method based on the system specifically comprises the following steps:

1) When the bus III main power supply fails, a bus III-bus II bus and an off-site power supply 2-way standby power supply exist, and if the bus II and the bus I run in a split mode, the first standby is a bus-connected breaker 4DL and the second standby is an off-site power supply breaker 5DL; if the bus II and the bus III are in communication operation, the first backup is an off-site power circuit breaker 5DL, and the second backup is a bus-tie circuit breaker 4DL; in this case, a third-band will appear after the second standby action is successful, and the mode should be switched in time;

2) When the bus III is powered by a main power supply and the bus III runs with the bus II, 2 paths of standby power are provided for the off-site power circuit breaker 5DL and the bus-tie circuit breaker 3DL, wherein the standby power is the off-site power circuit breaker 5DL, and the standby power is the bus-tie circuit breaker 3DL; a third zone appears after the second standby action is successful, and the operation mode needs to be switched in time;

3) When the main incoming line of the bus III is stopped, the bus III is powered by the off-site power circuit breaker 5DL, and the bus III and the bus II are operated in a separated mode, only the bus-connected circuit breaker 4DL is used as a standby power supply;

2. A utility 10kV "three-segment five-wire" primary system according to claim 1, characterized in that:

For the bus II, the power supply 2B is a main power supply of the bus, the power supplies 1B and 3B are standby power supplies in a factory, and the incoming lines 1 and 2 are standby power supplies outside the factory;

for the bus III, the power supply 3B is the main power supply of the bus, the power supply 2B is the in-plant standby power supply, and the incoming line 2 is the out-plant standby power supply.

3. A utility 10kV "three-segment five-wire" primary system according to claim 1, characterized in that: