A power distribution system

Abstract

The application provides a power distribution system, comprising at least two units, a first bus unit and a switch unit, each unit comprising a power supply unit, a second bus unit and a third bus unit, the first end of the power supply unit being connected to the first end of the third bus unit, the second end of the third bus unit being connected to the first end of the second bus unit, the third end of the third bus unit being connected to the first end of the switch unit, the second end of the switch unit being connected to the first end of the first bus unit, and the second end of the first bus unit being connected to the second end of the second bus unit. The application can improve the reliability of power supply.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nuclear power plants, in particular to a power distribution system. BACKGROUND

[0002] For the existing nuclear power plant, the plant AC power supply system mainly includes main generator, safety class diesel generator set, SBO (Station Black-out) diesel generator set, mobile diesel generator set, additional diesel generator set, etc. According to the functions of the nuclear power plant AC power distribution system, the configuration of the AC power supply system is also different. In the operation of the power plant, the additional diesel generator set in the plant area provides a time window for power recovery after SBO and extends the maintenance time window (normal operation condition of the power plant) for planned maintenance and corrective maintenance of the emergency diesel generator. A dedicated power supply bus needs to be set as the access of the additional diesel generator and the sending of the emergency bus of the plant unit, but the dedicated power supply bus is a single power supply line structure, and the power supply reliability is low. SUMMARY

[0003] The present application provides a power distribution system to solve the problem of low power supply reliability.

[0004] The present application provides a power distribution system, comprising at least two units, a first bus unit and a switch unit, each unit comprising a power supply unit, a second bus unit and a third bus unit, the first end of the power supply unit being connected to the first end of the third bus unit, the second end of the third bus unit being connected to the first end of the second bus unit, the third end of the third bus unit being connected to the first end of the switch unit, the second end of the switch unit being connected to the first end of the first bus unit, and the second end of the first bus unit being connected to the second end of the second bus unit.

[0005] In the present application, the third end of the third bus unit in the at least two units is connected to the first end of the first bus unit through the switch unit, and as long as any one of the at least two units can supply power to the first bus unit, the first bus unit can supply power to the second bus unit in the other units, thereby improving the reliability of power supply of the power distribution system. BRIEF DESCRIPTION OF DRAWINGS

[0006] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0007] Figure 1is a structural schematic diagram of a power distribution system provided by an embodiment of the present application;

[0008] Figure 2 is a structural schematic diagram of a power distribution system provided by an embodiment of the present application. DETAILED DESCRIPTION

[0009] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0010] Please refer to Figure 1 , for example, a power distribution system with two units, Figure 1 is a structural schematic diagram of a power distribution system provided by an embodiment of the present application. As shown in Figure 1 , it includes at least two units 10, a first bus unit 20 and a switch unit 30, each unit includes a power supply unit 101, a second bus unit 102 and a third bus unit 103, the first end of the power supply unit 101 is connected to the first end of the third bus unit 103, the second end of the third bus unit 103 is connected to the first end of the second bus unit 102, the third end of the third bus unit 103 is connected to the first end of the switch unit 30, the second end of the switch unit 30 is connected to the first end of the first bus unit 20, and the second end of the first bus unit 20 is connected to the second end of the second bus unit 102.

[0011] Among them, the above-mentioned switch unit 30 can control the third end of the third bus unit 103 in each unit to be in communication or disconnected with the first end of the first bus unit 20, for example: Figure 1 As shown in , if the power supply unit 101 of the unit 11 fails and the other unit 12 operates normally, the power supply unit 101 in the unit 12 can supply power to the above-mentioned first bus unit 20 through the third bus unit 103, so that the second bus unit 102 of the above-mentioned unit 11 can be powered by the above-mentioned first bus unit 20.

[0012] It can be understood that the second bus unit 102 described above can be used to supply power to important electrical equipment in the unit, for example, in the case of planned maintenance and corrective maintenance of the emergency diesel generator, the second bus unit 102 needs to be powered to maintain the normal operation of the nuclear power plant during the maintenance time. The existing nuclear power plant generally sets up an additional diesel generator in the plant as an emergency diesel generator to extend the maintenance time window in the case of planned maintenance and corrective maintenance of the emergency diesel generator, and sets up a dedicated power supply bus as an additional diesel generator for access and power supply to the emergency bus of the unit in the plant, and needs to configure the same capacity equipment as the emergency diesel generator, set up the additional diesel generator plant and supporting facilities and structures, and the subsequent operation and maintenance are more complex. In the present application, the first bus unit can be used to supply power to the second bus unit in any unit, and the additional diesel generator set, the additional diesel generator plant and the supporting facilities and structures can be cancelled, which can reduce the investment in subsequent operation and maintenance, improve the economy of the nuclear power plant operation, and the multi-power line structure can also improve the reliability of power supply compared with the single-power line structure.

[0013] Specifically, for the power distribution system, when one unit is in normal operation or island operation, the first bus unit 20 can supply power to the second bus unit 102 in the unit, for example, one of the at least two units in normal operation can be referred to as a first unit, and the units other than the first unit in the at least two units can be referred to as a second unit. The switch unit can be used to control the third end of the third bus unit 103 in the first unit to communicate with the first end of the first bus unit 20, and control the third end of the third bus unit 103 in the second unit to be disconnected from the first end of the first bus unit 20. In this way, as long as the power supply unit 10 of any one unit in the power distribution system can supply power normally, the first bus unit 20 can be powered, and the second bus unit 102 of other units can be powered.

[0014] In the embodiment of the present application, the third end of the third bus unit 103 in the at least two units is connected to the first end of the first bus unit 20 through the switch unit 30. As long as any one of the at least two units 10 can supply power to the first bus unit 20, the first bus unit 20 can supply power to the second bus unit 102 in other units, thereby improving the reliability of power supply of the power distribution system.

[0015] In addition, the second bus unit 102 can also be connected to a diesel generator, and the power supply unit 101 can serve as the main power source in the unit, and the diesel generator can supply power to the second bus unit 102 when the power supply unit 101 cannot supply power. The second end of the second bus unit 12 of each unit is connected to the second end of the first bus unit 20, and the second bus unit 102 in any unit can also be directly powered through the first bus unit 20 when the power supply unit 101 cannot supply power, thereby reducing the workload of starting the diesel generator and the like.

[0016] Optionally, as shown in Figure 2 The switch unit 30 includes at least two sub-switch units, and the at least two sub-switch units correspond to the at least two units 10 one by one. The third end of the third bus unit 103 in each unit is connected to the first end of the corresponding sub-switch unit, and the second end of the corresponding sub-switch unit is connected to the first end of the first bus unit 103.

[0017] The number and connection relationship of the sub-switch units correspond to the number of the units 10 one by one. For example, the first unit 11 can correspond to the first sub-switch unit 31, and the second unit 12 can correspond to the second sub-switch unit 32. If the first unit 11 fails to supply power to the second bus unit 102, the first end and the second end of the first sub-switch unit 31 can be controlled to be disconnected, and the first end and the second end of the second sub-switch unit 32 can be controlled to be connected. In this way, the second unit 12 can supply power to the first bus unit 20 through the second sub-switch unit 32, and further supply power to the second bus unit 102 in the first unit 11. At a certain moment, only the first end and the second end of one of the at least two sub-switch units are in a connected state, and the first end and the second end of the other sub-switch units are in a disconnected state. The sub-switch unit in the connected state can correspond to any one of the normally powered units.

[0018] In this embodiment, the at least two sub-switch units correspond to the at least two units one by one. Whether the third end of the third bus unit 103 of the corresponding unit is connected to the first end of the first bus unit 20 can be controlled by controlling whether the first end and the second end of each sub-switch unit are connected. As long as any unit in the nuclear power plant can supply power to the first bus unit 20, the power supply of the second bus unit 102 of each unit can be realized.

[0019] Optionally, as shown in Figure 2 Each unit also includes a maintenance power supply 40, and the third end of the first bus unit is connected to the first end of the maintenance power supply 40.

[0020] In this embodiment, in the case of maintenance of the units, as long as any one unit in the nuclear power plant can supply power to the first bus unit 20, the power supply of the maintenance power supply 40 of each unit can be realized, and the safety of the maintenance is improved.

[0021] Alternatively, as shown in Figure 2 The first bus unit 20 includes a first bus 21, the second bus unit 102 includes a second bus 1021 and a third bus 1022, and the third bus unit 103 includes a fourth bus 1031, a fifth bus 1032, a sixth bus 1033, and a seventh bus 1034.

[0022] The first end of the power supply unit 101 is connected to the first end of the fourth bus 1031, the first end of the fifth bus 1032, the first end of the sixth bus 1033, and the first end of the seventh bus 1034. The second end of the fourth bus 1031 is connected to the first end of the second bus 1021. The second end of the fifth bus 1032 is connected to the first end of the third bus 1022. The second end of the seventh bus 1034 is connected to the first end of the switch unit 30. The second end of the switch unit 30 is connected to the first end of the first bus 21. The second end of the first bus 21 is connected to the second end of the second bus 1021. The third end of the first bus 21 is connected to the second end of the third bus 1022.

[0023] The fourth end of the first bus 21 is connected to the first end of the maintenance power supply 40.

[0024] It can be understood that the above-mentioned first bus 21 can be used as a dedicated power supply bus to supply power to the emergency buses, i.e., the second bus 1021 and the third bus 1022 in each unit. That is, each unit is configured with an incoming line circuit to supply power to the first bus 21 to supply power to the second bus 1021 and the third bus 1022 of each unit. For any one unit, other generator units in the nuclear power plant can be used as the power distribution power supply of the unit, thereby extending the maintenance time window for planned maintenance and corrective maintenance of the emergency diesel generator.

[0025] It should be noted that the incoming line circuit and the outgoing line circuit of all the above-mentioned buses can be provided with circuit breakers to improve the safety of the operation of the units.

[0026] In this embodiment, through the multi-power incoming line structure, as long as any one unit in the nuclear power plant can supply power to the first bus 21, the first bus 21 can supply power to the second bus 1021 and the third bus 1022 in each unit, and the power supply to the maintenance power supply 40 can be guaranteed, thereby improving the reliability of the power supply of the power distribution system.

[0027] Optionally, as shown in Figure 2 The power supply unit 101 includes a generator 1011, a first transformer 1012, a booster station 1013 and a first voltage transformation unit 1014. The first end of the booster station 1013 is connected to the first end of the first transformer 1012. The first end of the generator 1011 and the second end of the first transformer 1012 are connected to the first end of the first voltage transformation unit 1014. The first end of the generator 1011 is connected to the first end of the booster station 1013.

[0028] The second end of the first voltage transformation unit 1014 is connected to the first end of the fourth bus 1031. The third end of the first voltage transformation unit 1014 is connected to the first end of the fifth bus 1032. The fourth end of the first voltage transformation unit 1014 is connected to the first end of the sixth bus 1033. The fifth end of the first voltage transformation unit 1014 is connected to the first end of the seventh bus 1034.

[0029] Specifically, the first transformer 1012 described above can be a main transformer. The booster station 1013 described above is a 500kV booster station. The electrical energy generated by the generator 1011 can be transmitted to the power grid through the first transformer 1012 and the booster station 1013. The power grid can also transmit electrical energy to the booster station 1013. A switch can be provided between the first end of the generator 1011 and the first end of the first voltage transformation unit 1014. When the generator 1011 is in normal operation, the switch can be used to control the connection or disconnection between the first end of the generator 1011, the first end of the first voltage transformation unit 1014 and the first end of the booster station 1013. In the case of abnormal operation of the generator 1011, the switch can be used to disconnect the generator 1011 from other devices in the unit, so as to protect the safe operation of the unit.

[0030] Optionally, as shown in Figure 2 The first voltage transformation unit 1014 includes a second transformer 10141 and a third transformer 10142. The first end of the generator 1011 and the second end of the first transformer 1012 are connected to the first end of the second transformer 10141. The first end of the generator 1011 and the second end of the first transformer 1012 are connected to the first end of the third transformer 10142.

[0031] The second end of the second transformer 10141 is connected to the first end of the fourth bus 1031. The third end of the second transformer 10141 is connected to the first end of the fifth bus 1032. The second end of the third transformer 10142 is connected to the first end of the sixth bus 1033. The third end of the third transformer 10142 is connected to the first end of the seventh bus 1034.

[0032] Specifically, a switch can be arranged between each of the bus bars and the second transformer 10141 and the third transformer 10142, and when the second transformer 10141 and the third transformer 10142 are under maintenance or failure, the switch can be controlled to be in a connected state or a disconnected state, so as to ensure the safe operation of the unit.

[0033] Optionally, as shown in Figure 2 the power distribution system further includes an auxiliary power supply unit 50, the auxiliary power supply unit 50 includes an auxiliary switch station 51 and a second transformer unit 52, the first end of the auxiliary switch station 51 is connected to the first end of the second transformer unit 52, the second end of the second transformer unit 52 is connected to the third end of the fourth bus bar 1031, the third end of the second transformer unit 52 is connected to the third end of the fifth bus bar 1032, the fourth end of the second transformer unit 52 is connected to the second end of the sixth bus bar 1033, and the fifth end of the second transformer unit 52 is connected to the third end of the seventh bus bar 1034.

[0034] Specifically, the power distribution system can include multiple power supply modes, and the power supply unit 101 can be used as a main power supply mode. When the power supply unit 101 is under maintenance or failure, the auxiliary power supply unit 50 can be used to supply power to the electrical equipment in the unit. The 220kV auxiliary switch station 51 can transmit the power of the power grid to the power distribution system. For example, when the generator 1011, the first transformer 1012, and the booster station 1013 in the power supply unit 101 are under maintenance or failure, the auxiliary power supply unit 50 can supply power to the fourth bus bar 1031, the fifth bus bar 1032, the sixth bus bar 1033, and the seventh bus bar 1034, respectively, and then supply power to the second bus bar 1021 and the third bus bar 1022, so as to meet the power demand of the power distribution system.

[0035] In addition, the auxiliary power supply unit 50 can supply power to the seventh bus bar 1034, thereby ensuring the power supply of the first bus bar unit 20, and supplying power to the second bus bar unit 102 of other units, thereby further improving the reliability of the power distribution system.

[0036] Optionally, as shown in Figure 2 the second transformer unit 52 includes a fourth transformer 521 and a fifth transformer 522, and the first end of the auxiliary switch station 51 is connected to the first end of the fourth transformer 521 and the first end of the fifth transformer 522.

[0037] The second end of the fourth transformer 521 is connected to the third end of the fourth bus 1031, the third end of the fourth transformer 521 is connected to the second end of the sixth bus 1033, the second end of the fifth transformer 522 is connected to the third end of the fifth bus 1032, and the third end of the fifth transformer 522 is connected to the third end of the seventh bus 1034.

[0038] It can be understood that the fourth transformer 521 and the fifth transformer 522 can be auxiliary transformers, and each of them divides two branches to supply power to the third bus unit 103, thereby improving the economy of the power distribution system.

[0039] It should be noted that in this document, the terms "comprise", "comprising", or any other variant thereof are intended to cover non-exclusive inclusions, so that processes, methods, articles, or devices that include a series of elements not only include those elements, but also include other elements not explicitly listed, or inherent to such processes, methods, articles, or devices. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of other identical elements in the process, method, article, or device that includes the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to the order of performing the functions shown or discussed, but can also include performing the functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method can be performed in an order different from the described order, and various steps can also be added, omitted, or combined. In addition, the features described with reference to certain examples can be combined in other examples.

[0040] The embodiments of the present application are described above in combination with the drawings, but the present application is not limited to the above-described specific embodiments, which are only illustrative and not limiting. Those skilled in the art can make many forms under the inspiration of the present application without departing from the scope of the present application and the scope of protection of the claims, which are all within the scope of protection of the present application.

Claims

1. A power distribution system, characterized by, The power supply unit is connected with the fourth bus bar, the fifth bus bar, the sixth bus bar and the seventh bus bar at the first end, the second end of the fourth bus bar is connected with the first end of the second bus bar, the second end of the fifth bus bar is connected with the first end of the third bus bar, the second end of the seventh bus bar is connected with the first end of the switch unit, the second end of the switch unit is connected with the first end of the first bus bar, the second end of the first bus bar is connected with the second end of the second bus bar, and the third end of the first bus bar is connected with the second end of the third bus bar. The fourth end of the first bus bar is connected with the first end of the maintenance power supply. The switch unit comprises at least two sub-switch units, the at least two sub-switch units correspond to the at least two units one by one, the third end of the third bus bar unit in each unit is connected with the first end of the corresponding sub-switch unit, and the second end of the corresponding sub-switch unit is connected with the first end of the first bus bar unit. The power supply unit comprises a generator, a first transformer, a boosting station and a first voltage conversion unit, the first end of the boosting station is connected with the first end of the first transformer, the first end of the generator and the second end of the first transformer are connected with the first end of the first voltage conversion unit, and the first end of the generator is connected with the first end of the boosting station. The second end of the first voltage conversion unit is connected with the first end of the fourth bus bar, the third end of the first voltage conversion unit is connected with the first end of the fifth bus bar, the fourth end of the first voltage conversion unit is connected with the first end of the sixth bus bar, and the fifth end of the first voltage conversion unit is connected with the first end of the seventh bus bar.

2. The power distribution system of claim 1, wherein, The first voltage conversion unit comprises a second transformer and a third transformer, the first end of the generator and the second end of the first transformer are connected with the first end of the second transformer, and the first end of the generator and the second end of the first transformer are connected with the first end of the third transformer.

3. The power distribution system of claim 1, wherein, The first voltage conversion unit comprises a second transformer and a third transformer, the first end of the generator and the second end of the first transformer are connected with the first end of the second transformer, and the first end of the generator and the second end of the first transformer are connected with the first end of the third transformer. ​ 4. The power distribution system of claim 3, wherein, ​ The second end of the second transformer is connected to the first end of the fourth bus, the third end of the second transformer is connected to the first end of the fifth bus, the second end of the third transformer is connected to the first end of the sixth bus, and the third end of the third transformer is connected to the first end of the seventh bus.

5. The power distribution system of claim 3, wherein, The power distribution system further comprises an auxiliary power supply unit, the auxiliary power supply unit comprising an auxiliary switch station and a second transformer unit, the first end of the auxiliary switch station being connected to the first end of the second transformer unit, the second end of the second transformer unit being connected to the third end of the fourth bus, the third end of the second transformer unit being connected to the third end of the fifth bus, the fourth end of the second transformer unit being connected to the second end of the sixth bus, and the fifth end of the second transformer unit being connected to the third end of the seventh bus.

6. The power distribution system of claim 5, wherein, The second transformer unit comprises a fourth transformer and a fifth transformer, and the first end of the auxiliary switch station is connected to the first end of the fourth transformer and the first end of the fifth transformer. The second end of the fourth transformer is connected to the third end of the fourth bus, the third end of the fourth transformer is connected to the second end of the sixth bus, the second end of the fifth transformer is connected to the third end of the fifth bus, and the third end of the fifth transformer is connected to the third end of the seventh bus.

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