DC power supply and distribution system and method of nuclear power station facing computing power data center

Abstract

The invention belongs to the technical field of power supply and distribution systems, and discloses a direct current power supply and distribution system and method of a nuclear power station facing a computing power data center, and the system comprises a direct current power supply and distribution architecture of a main power supply system, a medium-voltage direct current system and a low-voltage direct current system. Alternating current of a main power supply system is converted into medium-voltage direct current to be supplied to a medium-voltage direct current system through a first voltage conversion module, then the medium-voltage direct current is converted into low-voltage direct current to be supplied to a low-voltage direct current system through a second voltage conversion module, and the medium-voltage direct current system directly supplies power to a low-voltage system when a main power supply fails. And when the main power supply and the medium-voltage system both fail, the low-voltage system operates independently to meet the load requirement. By adopting the system, the equipment investment and the operation cost are obviously reduced, the electric energy transmission efficiency and the power supply reliability are improved, the potential safety hazard is eliminated, and the efficient cooperative power supply of the station power of the nuclear power station and the load of the data center is realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power supply and distribution system, and particularly relates to a direct current power supply and distribution system and method for a nuclear power plant for computing power data center. BACKGROUND

[0002] With the rapid development of digital technologies such as artificial intelligence and cloud computing, the demand for computing power is growing exponentially. Data centers, as the core of computing power, have continued to expand in size and quantity, leading to a rapid increase in electricity consumption. Power supply capacity has become a key bottleneck restricting the high-quality development of data centers. Under the guidance of the "double carbon" goal, data centers have an increasingly urgent demand for green and low-carbon electricity. Nuclear power, with its high energy density, extremely low carbon emissions, and stable and controllable output power, can provide economic, efficient, clean, environmentally friendly, and reliable power support for data centers. Therefore, building special small and medium-sized nuclear power plants for data centers to provide targeted power supply has become a promising development direction to break through the energy dilemma of data centers and promote the green transformation of the industry.

[0003] Currently, typical small and medium-sized nuclear power plant auxiliary power systems generally adopt the traditional power supply architecture of "medium-voltage alternating current + auxiliary low-voltage direct current". This architecture mainly adapts to the conventional power demand of nuclear power plants and does not consider the special load characteristics of data centers. The core equipment of data centers is mostly large-capacity direct current loads. If these loads are connected to the medium-voltage alternating current system of the nuclear power plant, an additional AC / DC conversion link is needed, which not only increases the investment cost of equipment but also significantly reduces the efficiency of power transmission. The presence of the conversion link also increases the risk of failure and affects the reliability of power supply. If the direct current loads of data centers are connected to the auxiliary low-voltage direct current system of the nuclear power plant, the low voltage level of the system cannot meet the power supply demand of large-capacity loads in data centers, which may lead to voltage fluctuations, insufficient power supply stability, and even safety hazards. On the other hand, the mainstream power supply architecture of data centers currently uses grid power as the core power source, and its design standards, connection methods, and operation control logic do not consider the connection requirements of nuclear power units. It is not compatible with the operation characteristics and safety requirements of nuclear power units, making it difficult to achieve efficient and collaborative power supply between nuclear power units and data centers.

[0004] Therefore, the existing power supply and distribution method cannot simultaneously meet the power demand of small and medium-sized nuclear power plant auxiliary power and data center direct current loads. SUMMARY

[0005] The application provides a direct current power supply and distribution system and method for a nuclear power plant for computing power data center. The system can simultaneously meet the power demand of small and medium-sized nuclear power plant auxiliary power and data center direct current loads, thereby ensuring the stability and safety of power supply and distribution.

[0006] To achieve the above purpose, the application adopts the following technical content: A direct current power supply and distribution system of a nuclear power plant facing computing power data center, comprising: a main power supply system, a medium voltage direct current system and a low voltage direct current system; The main power supply system is connected with the medium voltage direct current system through a first voltage conversion module; the first voltage conversion module is used for converting alternating current of the main power supply system into medium voltage direct current and transmitting the medium voltage direct current to the medium voltage direct current system; The medium voltage direct current system is connected with the low voltage direct current system through a second voltage conversion module; the second voltage conversion module is used for converting medium voltage direct current of the medium voltage direct current system into low voltage direct current and transmitting the low voltage direct current to the low voltage direct current system; Wherein, in normal operation, the main power supply system is used for supplying power to the medium voltage direct current system and the low voltage direct current system; when the main power supply system fails, the first voltage conversion module is disconnected, and the medium voltage direct current system can supply power to the low voltage direct current system; when the main power supply system and the medium voltage direct current system cannot supply power, the second voltage conversion module is disconnected, and the low voltage direct current system can meet its own load demand.

[0007] Further, the main power supply system comprises a nuclear power unit, a main power grid, an auxiliary power grid, a first switch device, a double-winding transformer and an auxiliary alternating current bus; The nuclear power unit is connected with the first voltage conversion module through the first switch device; The main power grid is connected with the first voltage conversion module through the first switch device, the double-winding transformer and the first voltage conversion module connected in series; The nuclear power unit and the main power grid are connected to the same node of the first voltage conversion module; wherein the nuclear power unit can transmit electric energy to the first voltage conversion module and the main power grid; the main power grid can transmit electric energy to the first voltage conversion module; The auxiliary power grid is connected with the first voltage conversion module through the first switch device, the double-winding transformer, the auxiliary alternating current bus and the first voltage conversion module connected in series; the auxiliary power grid can transmit electric energy to the first voltage conversion module.

[0008] Further, the first switch device comprises two disconnectors, and a circuit breaker is connected in series between the two disconnectors.

[0009] Further, the first voltage conversion module comprises a first switch device, a split transformer, a second switch device and a one-way AC-DC converter; The node connected with the main power grid is connected with the nuclear power unit through a first switch device, a split transformer, a unidirectional AC-DC converter, a second switch device and a medium-voltage direct-current system in sequence; the node connected with the main power grid is connected with two split transformers respectively, and each split transformer is connected with two independent medium-voltage direct-current systems respectively, for converting alternating current of the nuclear power unit or the main power grid into medium-voltage direct current and transmitting the medium-voltage direct current to the medium-voltage direct-current system; The node connected with the auxiliary power grid is connected with the medium-voltage direct-current system through a second switch device and a unidirectional AC-DC converter in sequence; Each auxiliary power grid is connected with two unidirectional AC-DC converters and two different medium-voltage direct-current systems respectively, for converting alternating current of the auxiliary power grid into medium-voltage direct current and transmitting the medium-voltage direct current to the medium-voltage direct-current system.

[0010] Further, the second switch device comprises disconnectors and circuit breakers, which are connected in sequence and connected with two disconnectors respectively.

[0011] Further, the medium-voltage direct-current system comprises a first switch device, a second switch device, a standby diesel generator, a third switch device, a first bus, a unidirectional DC-AC converter, a direct-current energy storage system and a medium-voltage VFD motor load. The first bus comprises a plurality of separate buses and a third switch device; wherein two buses are connected through the third switch device to form a double-bus sectional wiring structure; the first bus is connected with the second switch device to realize that when the bus fails or is under maintenance, the operation of the remaining system can be restored through switching operation; The standby diesel generator is connected with the first bus through a first switch device, a unidirectional AC-DC converter and a second switch device in sequence. The medium-voltage VFD motor load is connected with the first bus through a first switch device, a unidirectional DC-AC converter and a second switch device in sequence. The direct-current energy storage system is connected with the first bus through the second switch device. The first bus is connected with a first voltage conversion module and a second voltage conversion module respectively.

[0012] Further, the second voltage conversion module comprises a second switch device and a unidirectional DC-DC converter. The medium-voltage direct-current system is connected with a low-voltage direct-current system through a second switch device and a unidirectional DC-DC converter in sequence. The second voltage conversion module reduces the voltage of the medium-voltage direct current of the medium-voltage direct-current system and transmits the reduced medium-voltage direct current to the low-voltage direct-current system.

[0013] Further, the low-voltage direct-current system comprises a first switch device, a second switch device, a third switch device, a unidirectional DC-AC converter, a direct-current energy storage system, a second bus, an IT load and a low-voltage VFD motor load. The second bus comprises a plurality of buses and a third switch device, and each two buses are connected through the third switch device to form a double-bus tie-in structure. The second bus is connected with the second switch device, so that when the bus fails or is under maintenance, the operation of the remaining system can be restored through switching operation. The low-voltage VFD motor load is connected with the second bus through the first switch device, the unidirectional DC-AC converter and the second switch device connected in sequence; the unidirectional DC-AC converter can convert the low-voltage direct current of the second bus into low-voltage alternating current and transmit it to the low-voltage VFD motor load. The direct-current energy storage system is connected with the second bus through the second switch device. The IT load is connected with the second bus through the second switch device. The second voltage conversion module is connected with the second bus.

[0014] Further, the voltage level of the medium-voltage direct-current system is 10kV or 20kV; and the voltage level of the low-voltage direct-current system is 800V or 1kV.

[0015] A working method of a direct-current power supply and distribution system of a nuclear power plant for a computing power data center, based on the direct-current power supply and distribution system of the nuclear power plant for the computing power data center, comprising: The first voltage conversion module is used for converting alternating current of the main power supply system into medium-voltage direct current and transmitting the medium-voltage direct current to the medium-voltage direct-current system. The second voltage conversion module is used for converting the medium-voltage direct current of the medium-voltage direct-current system into low-voltage direct current and transmitting the low-voltage direct current to the low-voltage direct-current system. When normally operating, the main power supply system is used for supplying power to the medium-voltage direct-current system and the low-voltage direct-current system respectively. When the main power supply system fails, the first voltage conversion module is disconnected, and the medium-voltage direct-current system is used for supplying power to the low-voltage direct-current system. When the main power supply system and the medium-voltage direct-current system cannot supply power, the second voltage conversion module is disconnected, so that the low-voltage direct-current system can meet its own load demand.

[0016] Compared with the prior art, the present application has the following beneficial effects: The application provides a direct current power supply and distribution system for a nuclear power station facing computing power data centers, comprising a direct current power supply and distribution architecture of a main power supply system, a medium voltage direct current system and a low voltage direct current system, the main power supply system is converted into medium voltage direct current by a first voltage conversion module to supply the medium voltage direct current system, and the medium voltage direct current is converted into low voltage direct current by a second voltage conversion module to supply the low voltage direct current system, and the medium voltage system directly supplies the low voltage system when the main power supply fails, and the low voltage system independently operates to meet the load demand when the main power supply and the medium voltage system both fail. The system directly adopts a direct current power supply mode according to the direct current load characteristics of the data center, avoiding the energy loss and failure risk caused by the additional AC / DC conversion link in the traditional AC system; at the same time, the voltage level design of the medium voltage direct current system effectively overcomes the voltage fluctuation problem caused by the insufficient capacity of the low voltage system, improving the system stability; and the failure switching mechanism enhances the fault tolerance through hierarchical redundancy design. The use of the system significantly reduces the equipment investment and operation cost, improves the power transmission efficiency and power supply reliability, eliminates potential safety hazards, and realizes efficient collaborative power supply of nuclear power station auxiliary power and data center load.

[0017] Preferably, in the application, the nuclear power unit, the main power grid and the auxiliary power grid are integrated in the main power supply system, and the multi-power interconnection is realized through the switching device, the transformer and the bus, thereby enhancing the system redundancy and flexibility. The nuclear power unit and the main power grid can back up each other for power supply, and the auxiliary power grid provides an independent backup path, so that the input of the medium voltage direct current system can be maintained when the main power supply fails, thereby overcoming the risk of power supply interruption caused by single power dependence. Overall, the design improves the collaboration ability of the nuclear power station and the external power grid, and strengthens the continuous power supply stability of the system under abnormal working conditions.

[0018] Preferably, in the application, the first switching device is composed of an isolating switch and a circuit breaker in series, thereby enhancing the electrical isolation and fault protection capability. The isolating switch ensures the operation safety during equipment maintenance, and the circuit breaker quickly cuts off the short circuit fault to reduce the influence of fault diffusion, thereby improving the safety and operation reliability of the whole system. This design effectively alleviates the fault risk caused by the complexity of the conversion link and simplifies the system operation and maintenance management.

[0019] Preferably, in the application, the first voltage conversion module is constructed by a split transformer and a plurality of unidirectional converters, supporting the parallel input of the nuclear power unit and the main power grid, and independently connecting the auxiliary power grid. The split transformer realizes multi-path parallel conversion, improving the system capacity and redundancy; and the auxiliary power grid is directly connected through the converter, reducing the conversion level. This solves the problem of low conversion efficiency of AC / DC, optimizes the power transmission path, and enhances the adaptability and fault tolerance of the system to large loads.

[0020] Preferably, in the present application, the disconnectors are connected in series with the circuit breakers and expanded to multiple connections, providing more stringent electrical isolation and sectionalization protection. It realizes rapid fault isolation and flexible switching of power supply path, reduces the hidden danger of local fault to the overall system background technology of low-voltage system power supply shortage.

[0021] Preferably, in the present application, the medium-voltage DC system introduces a double-bus sectionalization structure, a standby diesel generator and a DC energy storage system, optimizing system resilience and load management. The double-bus design supports rapid switching operation during faults, ensuring uninterrupted system operation during partial bus maintenance; the standby generator and energy storage device provide emergency power and load smoothing capability, effectively responding to main power failure scenarios. This enhances the system's support for large-capacity loads in data centers, solving the problem of voltage fluctuation and insufficient power supply stability.

[0022] Preferably, in the present application, a unidirectional DC converter is used to achieve efficient step-down conversion from medium voltage to low voltage, simplifying the voltage conversion process. It reduces energy loss and device complexity, ensuring stable input for the low-voltage DC system, thereby directly matching the characteristics of the core load in the data center, improving power utilization efficiency and system economy, and avoiding the cost increase caused by additional conversion steps.

[0023] Preferably, in the present application, a double-bus interconnection structure and a DC energy storage system are applied in the low-voltage DC system and directly connected to the IT load. The double-bus design improves power supply reliability and maintainability; the energy storage device supports peak load buffering and backup power supply; the IT load DC direct supply reduces conversion loss. Overall, it optimizes the power supply quality of the data center load, solves the safety hidden danger of insufficient capacity of the low-voltage system, and improves the overall collaborative efficiency of the system.

[0024] The application further provides a working method of a direct current power supply and distribution system of a nuclear power station facing a computing power data center. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 A topological structure diagram of a direct current power supply and distribution system of a nuclear power station facing a computing power data center is provided for the embodiment of the application. Figure 2 A schematic diagram of a power supply part of a direct current power supply and distribution system of a nuclear power station facing a computing power data center is provided for the embodiment of the application. Figure 3 A schematic diagram of a direct current part of a direct current power supply and distribution system of a nuclear power station facing a computing power data center is provided for the embodiment of the application.

[0026] REFERENCE NUMERALS 1, main power supply system; 2, first voltage conversion module; 3, medium voltage direct current system; 4, second voltage conversion module; 5, low voltage direct current system; 6, main power grid; 7, auxiliary power grid; 8, first switch device; 9, double-winding transformer; 10, auxiliary alternating current bus; 11, nuclear power unit; 12, split transformer; 13, one-way AC-DC converter; 14, second switch device; 15, standby diesel generator; 16, third switch device; 17, first bus; 18, one-way DC-AC converter; 19, direct current energy storage system; 20, medium voltage VFD motor load; 21, one-way DC-DC converter; 22, second bus; 23, IT load; 24, low voltage VFD motor load. DETAILED DESCRIPTION

[0027] To make the technical problems solved by the present invention, the technical solutions, and the beneficial effects clearer, the following specific embodiments provide a further detailed description of the present invention. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of the invention.

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0030] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0031] As mentioned in the background section, a typical nuclear power plant auxiliary power system adopts a "medium-voltage AC + auxiliary low-voltage DC" power supply architecture. However, data centers contain large-capacity DC loads. Connecting them to a medium-voltage AC system would add an extra AC-DC conversion stage, resulting in low power transmission efficiency and low power supply reliability. Connecting them to an auxiliary low-voltage DC system would affect the stability and safety of the power supply due to excessively low voltage. Currently, data centers primarily rely on grid power, and their power supply architecture does not consider the integration of nuclear power units and does not meet the operational requirements of nuclear power units.

[0032] To address the aforementioned issues, this embodiment provides a DC power supply and distribution system for a nuclear power plant oriented towards a computing data center. This system uses nuclear power as its primary energy source and can simultaneously meet the power needs of both the nuclear power plant and the data center load.

[0033] The DC power supply and distribution system for a nuclear power plant oriented towards a computing data center, as provided in this embodiment, will be further described below with reference to the accompanying drawings: In this embodiment, the nuclear power plant is a small and medium-sized nuclear power plant; preferably a small modular reactor (SMR) nuclear power plant, but not limited to this, it can also be a micro reactor, a fast reactor or other small and medium-sized capacity nuclear power units that can be deployed near the load; the nuclear power unit directly supplies power to the data center load, which is one of the main loads of the small and medium-sized nuclear power plant, and preferably adopts the same priority power supply strategy as the auxiliary power load.

[0034] As shown in Figure 1 The embodiment provides a direct current power supply and distribution system of a nuclear power plant for a computing power data center, which comprises a main power supply system 1, a medium-voltage direct current system 3, a low-voltage direct current system 5, and a first voltage conversion module 2 and a second voltage conversion module 4 for connecting the systems; the specific connection relationship and functions are as follows: The power supply system 1 is connected with the medium-voltage direct current system 3 through the first voltage conversion module 2.

[0035] The first voltage conversion module 2 is used for converting the alternating current of the main power supply system 1 into medium-voltage direct current and transmitting it to the medium-voltage direct current system 3.

[0036] The medium-voltage direct current system 3 is connected with the low-voltage direct current system 5 through the second voltage conversion module 4.

[0037] The second voltage conversion module 4 is used for converting the medium-voltage direct current of the medium-voltage direct current system 3 into low-voltage direct current and transmitting it to the low-voltage direct current system 5.

[0038] For example, the voltage level of the medium-voltage direct current system 3 is preferably 10kV or 20kV, and the voltage level of the low-voltage direct current system 5 is preferably 800V or 1kV.

[0039] Based on the direct current power supply and distribution system of the nuclear power plant for the computing power data center, the following power supply modes are switched to ensure stable power supply for system load under fault or maintenance conditions, and the specific power supply mode switching is as follows: 1) When normally operating, the main power supply system 1 supplies power to the medium-voltage direct current system 3 and the low-voltage direct current system 5.

[0040] 2) When the main power supply system 1 cannot supply power, the first voltage conversion module 2 is disconnected, and the medium-voltage direct current system 3 supplies power to the low-voltage direct current system 5.

[0041] 3) When the main power supply system 1 and the medium-voltage direct current system 3 cannot supply power, the second voltage conversion module 4 is disconnected, and the low-voltage direct current system 5 meets its own load demand.

[0042] Based on the direct current power supply and distribution system of the nuclear power plant for the computing power data center, the embodiment further provides a working method of the direct current power supply and distribution system of the nuclear power plant for the computing power data center, and the specific steps are as follows: The first voltage conversion module 2 converts the AC power of the main power supply system 1 into medium-voltage DC power and transmits the medium-voltage DC power to the medium-voltage DC system 3; The second voltage conversion module 4 is used for converting the medium-voltage DC power of the medium-voltage DC system 3 into low-voltage DC power and transmitting the low-voltage DC power to the low-voltage DC system 5; In normal operation, the main power supply system 1 supplies power to the medium-voltage DC system 3 and the low-voltage DC system 5 respectively; When the main power supply system 1 fails, the first voltage conversion module 2 is disconnected, and the medium-voltage DC system 3 can supply power to the low-voltage DC system 5; When the main power supply system 1 and the medium-voltage DC system 3 cannot supply power, the second voltage conversion module 4 is disconnected, so that the low-voltage DC system 5 can meet its own load demand.

[0043] For example, as shown in the figure, Figure 2 In the embodiment, the main power supply system includes a nuclear power unit 11, a main power grid 6, an auxiliary power grid 7, a first switching device 8, a double-winding transformer 9, and an auxiliary AC bus 10.

[0044] The first switching device 8 is composed of an isolating switch, a circuit breaker, and another isolating switch connected in series, and is used to change the connection relationship between the components.

[0045] The nuclear power unit 11 is connected to the first voltage conversion module 2 through the first switching device 8. The main power grid 6 is connected to the first voltage conversion module 2 through the first switching device 8, the double-winding transformer 9, another first switching device 8 connected in series. The nuclear power unit 11 and the main power grid 6 are connected to the same node of the first voltage conversion module 2. The nuclear power unit 11 can transmit power to the first voltage conversion module 2 and the main power grid 6; the main power grid 6 can transmit power to the first voltage conversion module 2.

[0046] The auxiliary power grid 7 is connected to the first voltage conversion module 2 through the first switching device 8, the double-winding transformer 9, another first switching device 8, the auxiliary AC bus 10 connected in series. The auxiliary power grid 7 can transmit power to the first voltage conversion module 2.

[0047] The power supply system 1 can complete the switching of the nuclear power unit 11, the main power grid 6, and the auxiliary power grid 7 through the opening and closing of the first switching device 8. Thus, in the case of partial power failure, power can still be transmitted to the first voltage conversion module 2. Specifically: (1) When the nuclear power unit 11 is in normal operation: If the rated power of the nuclear power unit 11 is greater than the system load, the first switch device 8 connected to the auxiliary power grid 7 is disconnected. The main power of the nuclear power unit 11 is transmitted to the first voltage conversion module 2, and the excess power is transmitted through the main power grid 6.

[0048] When the main power grid 6 cannot transmit power, the first switch device 8 connected to the auxiliary power grid 7 is disconnected, and the first switch device 8 connected to the main power grid 6 is disconnected. The nuclear power unit 11 starts the HLO (House-Load Operation) function to reduce its output power, and transmits the power to the first voltage conversion module 2.

[0049] If the rated power of the nuclear power unit 11 is less than the system load, the first switch device 8 connected to the auxiliary power grid 7 is disconnected. The nuclear power unit 11 bears the basic load of the system, and its power is transmitted to the first voltage conversion module 2. The main power grid bears the remaining load of the system, and its power is transmitted to the first voltage conversion module 2.

[0050] When the main power grid 6 cannot provide power, the first switch device 8 connected to the main power grid 6 is disconnected, and the first switch device 8 connected to the auxiliary power grid 7 is closed. The auxiliary power grid bears the remaining load of the system, and its power is transmitted to the first voltage conversion module 2.

[0051] When the main power grid 6 and the auxiliary power grid 7 cannot provide power, the first switch device 8 connected to the main power grid 6 and the auxiliary power grid 7 is disconnected, and the remaining power of the system is borne by the medium-voltage DC system 3 and the low-voltage DC system 5.

[0052] (2) When the nuclear power unit 11 fails, the first switch device 8 connected to the auxiliary power grid 7 and the nuclear power unit 11 is disconnected, and the main power grid 6 supplies power to other subsystems.

[0053] (3) When the nuclear power unit 11 fails and cannot obtain power from the main power grid 6, the first switch device 8 connected to the nuclear power unit 11 and the main power grid 6 is disconnected, and the first switch device 8 connected to the auxiliary power grid 7 is closed. The auxiliary power grid 7 supplies power to other subsystems.

[0054] As can be seen, the power supply architecture considers the access of the nuclear power unit, and designs the main power switching method in the case that the power of the nuclear power unit is greater than the system load and the power of the nuclear power unit is less than the system load.

[0055] In this embodiment, the first voltage conversion module 2 includes the first switch device 8, the split transformer 12, the second switch device 14 and the unidirectional AC-DC converter 13. It can be explained that the second switch device 14 is composed of two additional disconnectors connected in parallel after the disconnector and circuit breaker. The second switch device 14 can change the connection relationship between the lines through switching operation.

[0056] The node connecting nuclear power unit 11 to the main power grid 6 is connected to the medium-voltage DC system 3 via a series connection of a first switching device 8, a split transformer 12, another first switching device 8, a unidirectional AC-DC converter 13, and a second switching device 14. This node is connected in parallel to two split transformers 12, each of which is connected to two different medium-voltage DC systems 3. This is used to convert the AC power from nuclear power unit 11 or the main power grid 6 into medium-voltage DC power and transmit it to the medium-voltage DC system 3.

[0057] The nodes connected to the auxiliary power grid 7 are connected to the medium-voltage DC system 3 via a second switching device 14, a unidirectional AC-DC converter 13, and another second switching device 14 connected in series. Each auxiliary power grid 7 is connected to two unidirectional AC-DC converters 13 and two different medium-voltage DC systems 3, which are used to convert the AC power of the auxiliary power grid 7 into medium-voltage DC power and transmit it to the medium-voltage DC system 3.

[0058] The first voltage conversion module 2 adopts a redundant topology. When it fails or is under maintenance, it can shut down and isolate a designated split transformer 12 or unidirectional AC-DC converter 13 and its connected lines, thereby ensuring the safe and stable operation of the remaining system. Specifically, when a split transformer 12 or unidirectional AC-DC converter 13 or its connected lines need to be shut down and isolated, the first switching device 8 and the second switching device 14 corresponding to the split transformer 12 or unidirectional AC-DC converter 13 are disconnected, ensuring the stable operation of the remaining system.

[0059] For example, in this embodiment, such as Figure 3 As shown, the medium-voltage DC system 3 includes a first switching device 8, a second switching device 14, a standby diesel generator 15, a third switching device 16, a first busbar 17, a unidirectional DC-AC converter 18, a DC energy storage system 19, and a medium-voltage VFD motor load 20. The third switching device 16 is explained as consisting of a disconnecting switch, a circuit breaker, a reactor (optional), and another disconnecting switch connected in series, used to change the internal connection relationship of the busbar.

[0060] The first busbar 17 consists of three individual busbars and a third switchgear 16. Every two busbars are connected by the third switchgear 16, forming a double busbar segmented wiring structure. The first busbar 17 is connected to other components through the second switchgear 14, so that in the event of a busbar failure or maintenance, the stable operation of the remaining system can be restored through switching operations.

[0061] The backup diesel generator 15 is connected to the first bus 17 via a first switching device 8, a unidirectional AC-DC converter 13, and a second switching device 14 connected in series. When the first voltage conversion module 2 fails to supply power, the backup diesel generator 15 can supply power to the medium-voltage DC system 3 and other subsystems.

[0062] The medium-voltage VFD motor load 20 is connected to the first bus 17 through the first switch device 8, the unidirectional DC-AC converter 18 and the second switch device 14 in sequence, and obtains required power from the first bus 17.

[0063] The DC energy storage system 19 is connected to the first bus 17 through the second switch device 14. In normal operation, the first bus 17 transmits power to the DC energy storage system 19, and the DC energy storage system 19 is charged. When the first voltage conversion module 2 cannot supply power, the DC energy storage system 19 transmits power to the first bus 17 to supply power to the medium-voltage DC system 3 and other subsystems.

[0064] The first voltage conversion module 2 is connected to the first bus 17. In normal operation, DC power is transmitted from the first voltage conversion module 2 to the first bus 17.

[0065] The second voltage conversion module 4 is connected to the first bus 17. In normal operation, DC power is transmitted from the first bus 17 to the second voltage conversion module 4.

[0066] The medium-voltage DC system 3 can be switched between the following power supply modes to achieve power supply in different working conditions: (1) In normal operation, the first switch device 8 connected to the standby diesel generator 15 is opened, and the main power supply system 1 supplies power to the medium-voltage DC system 3 and other subsystems through the first voltage conversion module 2.

[0067] (2) When the main power supply system 1 cannot supply power, the DC energy storage system 19 can supply power. At this time, the first switch device 8 connected to the standby diesel generator 15 is opened, and the DC energy storage system 19 supplies power to the medium-voltage DC system 3 and other subsystems for a short time.

[0068] (3) When the main power supply system 1 cannot supply power, the standby diesel generator 15 can supply power. At this time, the first switch device 8 connected to the standby diesel generator 15 is closed, and the standby diesel generator 15 supplies power to the medium-voltage DC system 3 and other subsystems for a medium-long time.

[0069] As can be seen, the medium-voltage VFD motor load uses a medium-voltage DC bus for power supply through one-stage DC-AC conversion, reducing unnecessary AC-DC conversion links and improving power supply efficiency and reliability.

[0070] In this embodiment, the second voltage conversion module 4 includes the second switch device 14 and the unidirectional DC-DC converter 21.

[0071] In this embodiment, the medium-voltage DC system 3 is connected to the low-voltage DC system 5 by connecting the second switch device 14, the unidirectional DC-DC converter 21, another second switch device 14 in sequence. The second voltage conversion module 4 steps down the medium-voltage DC power of the medium-voltage DC system 3 and transmits it to the low-voltage DC system 5.

[0072] Through the above connection mode, the second voltage conversion module 4 adopts a redundant topology, which can shut down and isolate the specified unidirectional DC-DC converter 21 and the connected line when a failure or maintenance occurs in the second voltage conversion module 4, thereby ensuring the safe and stable operation of the remaining system. Specifically, when a unidirectional DC-DC converter 21 or the connected line needs to be shut down and isolated, the second switch device 14 connected to the unidirectional DC-DC converter 21 is disconnected, ensuring the stable operation of the remaining system.

[0073] In this embodiment, the low-voltage DC system 5 includes a first switch device 8, a second switch device 14, a third switch device 16, a unidirectional DC-AC converter 18, a DC energy storage system 19, a second bus 22, an IT load 23, and a low-voltage VFD motor load 24.

[0074] The second bus 22 is composed of four buses and the third switch device 16. The connection between the specified two buses is realized through the third switch device 16, forming a double-bus tie-in structure. The second bus 22 is connected to other components through the second switch device 14, so that when a bus failure or maintenance occurs, the stable operation of the remaining system can be restored through switching operation.

[0075] The low-voltage VFD motor load 24 is connected to the second bus 22 by connecting the first switch device 8, the unidirectional DC-AC converter 18, and the second switch device 14 in sequence. The unidirectional DC-AC converter 18 converts the low-voltage DC power of the second bus 22 into low-voltage AC power and transmits it to the low-voltage VFD motor load 24.

[0076] The DC energy storage system 19 is connected to the second bus 22 through the second switch device 14. In normal operation, the second bus 22 transmits power to the DC energy storage system 19, and the DC energy storage system 19 is charged. When the second voltage conversion module 4 fails to supply power, the DC energy storage system 19 transmits power to the second bus 22 to supply power to the low-voltage DC system 5.

[0077] The IT load 23 is connected to the second bus 22 through the second switch device 14 and obtains the required power from the second bus 22.

[0078] The second voltage conversion module 4 is connected to the second bus 22. In normal operation, the second voltage conversion module 4 transmits power to the second bus 22.

[0079] Therefore, the low-voltage DC system 5 can switch between the following power supply modes to achieve power supply under different operating conditions: (1) During normal operation, the second voltage conversion module 4 transmits electrical energy to the low-voltage DC system 5.

[0080] (2) When the second voltage conversion module 4 fails to supply power, the DC energy storage system 19 supplies power to the low-voltage DC system 5 via the second bus 22.

[0081] Based on the overall design of the low-voltage DC system 5, this system solves the following problems: (1) The low-voltage VFD motor load is powered by a low-voltage DC bus through a first-stage DC-AC converter, which reduces unnecessary AC-DC conversion links and improves power supply efficiency and reliability.

[0082] (2) IT loads are directly powered through the low-voltage DC bus, which reduces unnecessary AC / DC conversion links and improves power supply efficiency and reliability.

[0083] (3) The low-voltage DC bus voltage is preferably 800V or 1kV, which is significantly higher than the 240V auxiliary DC system used in nuclear power plants. When supplying power to the large-capacity IT load of data centers, it can effectively reduce the operating current and improve the stability of the power supply system.

[0084] In summary, this invention provides a DC power supply and distribution system and method for nuclear power plants targeting computing data centers, which has the following advantages compared to existing power supply and distribution technologies: First, this system takes into account the connection of small and medium-sized nuclear power units and is compatible with two types of loads: This system uses small and medium-sized nuclear power units as the main power source and considers the switching methods between nuclear power units and other power sources, thus solving the problem that typical data center power supply systems do not consider the connection of nuclear power units.

[0085] The main power loads of small and medium-sized nuclear power plants include VFD (Variable Frequency Drive) motor loads that are suitable for power supply from the DC bus via a single-stage DC-AC converter.

[0086] Data center loads mainly include: IT loads suitable for direct DC bus power supply, and their supporting VFD equipment. Among them, IT loads have larger capacities and require higher DC power supply voltages.

[0087] The power supply system of this invention is designed with a medium-voltage DC system and a low-voltage DC system to meet the needs of these loads. Specifically, the medium-voltage DC system handles the medium-voltage VFD motor load, while the low-voltage DC system handles the low-voltage VFD motor load and the IT load.

[0088] All major types of load have corresponding systems to bear, so the system design is compatible with small and medium-sized nuclear power plant auxiliary power and data center loads.

[0089] Second, the power supply system has high efficiency: Using nuclear power units to directly power the data center saves the intermediate link of power grid transmission and reduces power transmission losses.

[0090] VFD motor load uses a DC bus for power supply through a one-stage DC-AC conversion, and IT load uses a DC bus for direct power supply, saving unnecessary AC-DC conversion links and improving energy conversion efficiency.

[0091] Therefore, the power supply system has high power supply capacity, can reduce the number of equipment, reduce transmission power loss, and optimize the overall line layout.

[0092] Third, the power supply system has high availability and high reliability: The system uses nuclear power units as power supply, and the nuclear power unit has a long fuel supply cycle, strong energy independence and external impact resistance, and is not affected by climate and day-night changes, meeting the data center load requirements for long-time and large-capacity stable power supply.

[0093] The system is configured with nuclear power units, external power grids, backup diesel generators, and DC energy storage systems. When several power sources fail, power switching can be performed to ensure stable power supply for nuclear power plant auxiliary power and data center loads.

[0094] The system uses a redundant wiring structure, with double-bus sectional wiring and double-bus tie-in wiring structure for the bus, and redundant configuration for important voltage conversion modules such as transformers and converters, which can ensure stable operation of the remaining system through switching operation when faults occur or maintenance is required.

[0095] Therefore, the power supply system has high availability and high reliability, and can meet the stable operation requirements of nuclear power plant auxiliary power and data center loads.

[0096] Fourth, the power supply system has a modular feature: The system includes multiple medium-voltage DC systems, low-voltage DC systems, and second voltage conversion modules. Systems and modules with the same name have the same internal structure and function.

[0097] The power supply topology of the system is highly symmetrical. The structure and function of corresponding components in the same subsystem or module are completely the same.

[0098] Therefore, the power supply and distribution system can adopt modular design, and the power supply equipment can be designed with unified interface and standard to reduce manufacturing cost and improve manufacturing efficiency; the modular products can be prefabricated and tested in the factory to reduce installation time and construction error on site; the construction can be carried out in stages according to the capacity of the data center and flexible expansion; when a fault occurs, only the corresponding module needs to be replaced, without the need for whole system shutdown maintenance; when the system is expanded, the module can be added or replaced through the "plug and play" mode without the need to reconstruct the whole power supply system.

[0099] Fifth, the power supply and distribution system has expandability: The power supply and distribution system adopts modular design, and the subsystem or module can be replaced and expanded without affecting the normal operation of the remaining system. Therefore, the power supply and distribution system has expandability, and the structure and function of the system can be changed according to further requirements without the need to reconstruct the whole system. The expandability of the power supply and distribution system is specifically reflected in: (1) In order to further improve the reliability and availability of the power supply system, the low-voltage DC bus can adopt a ring network structure.

[0100] (2) In order to further improve the reliability and availability of the power supply system, the standby diesel generator can be connected to the low-voltage DC bus through rectification, and the number of standby diesel generators can be set according to the distributed or ring network low-voltage DC bus structure.

[0101] (3) In order to further improve the utilization rate of new energy, the medium-voltage DC bus and the low-voltage DC bus can be connected through a multi-port power electronic converter to connect photovoltaic, wind power and other distributed new energy.

[0102] (4) In order to further consider other load requirements, corresponding loads and related equipment can be added to the corresponding bus.

[0103] (5) Considering that the safety class constant speed motor of large nuclear power plants is gradually replaced by VFD motor, the power supply and distribution system can also be applied to large nuclear power plants containing auxiliary computing data centers.

[0104] The above embodiments are only one of the implementation manners of the technical solutions of the present application, and the scope of protection of the present application is not limited to the above embodiments, but also includes any changes, substitutions and other implementation manners easily thought by those skilled in the art within the technical scope disclosed by the present application.

Claims

1. A DC power supply and distribution system for a nuclear power plant oriented towards computing data centers, characterized in that, include: Main power system (1), medium voltage DC system (3) and low voltage DC system (5); The main power system (1) and the medium-voltage DC system (3) are connected through a first voltage conversion module (2); the first voltage conversion module (2) is used to convert the AC power of the main power system (1) into medium-voltage DC power and transmit the medium-voltage DC power to the medium-voltage DC system (3). The medium-voltage DC system (3) and the low-voltage DC system (5) are connected by a second voltage conversion module (4); the second voltage conversion module (4) is used to convert the medium-voltage DC power of the medium-voltage DC system (3) into low-voltage DC power and transmit the low-voltage DC power to the low-voltage DC system (5). During normal operation, the main power system (1) supplies power to the medium-voltage DC system (3) and the low-voltage DC system (5). When the main power system (1) fails, the first voltage conversion module (2) is disconnected, and the medium-voltage DC system (3) can supply power to the low-voltage DC system (5). When neither the main power system (1) nor the medium-voltage DC system (3) can supply power, the second voltage conversion module (4) is disconnected, and the low-voltage DC system (5) can meet its own load requirements.

2. The DC power supply and distribution system for a nuclear power plant oriented towards a computing data center according to claim 1, characterized in that, The main power system (1) includes a nuclear power unit (11), a main power grid (6), an auxiliary power grid (7), a first switching device (8), a double-winding transformer (9), and an auxiliary AC bus (10). The nuclear power unit (11) is connected to the first voltage conversion module (2) through the first switching device (8); The main power grid (6) is connected to the first voltage conversion module (2) via a first switching device (8) and a double-winding transformer (9) connected in series. The nuclear power unit (11) and the main power grid (6) are connected to the same node of the first voltage conversion module (2); wherein the nuclear power unit (11) is able to transmit electrical energy to the first voltage conversion module (2) and the main power grid (6); the main power grid (6) is able to transmit electrical energy to the first voltage conversion module (2); The auxiliary power grid (7) is connected to the first voltage conversion module (2) via a first switching device (8), a double-winding transformer (9), and an auxiliary AC bus (10) connected in series. The auxiliary power grid (7) can transmit electrical energy to the first voltage conversion module (2).

3. A DC power supply and distribution system for a nuclear power plant oriented towards a computing data center, as described in claim 2, is characterized in that... The first switching device (8) includes two disconnecting switches, and a circuit breaker is connected in series between the two disconnecting switches.

4. A DC power supply and distribution system for a nuclear power plant oriented towards a computing data center, as described in claim 2, is characterized in that... The first voltage conversion module (2) includes a first switching device (8), a split transformer (12), a second switching device (14), and a unidirectional AC-DC converter (13). The node connecting the nuclear power unit (11) and the main power grid (6) is connected to the medium-voltage DC system (3) via a first switching device (8), a split transformer (12), a unidirectional AC-DC converter (13), and a second switching device (14) connected in series. The node connecting the nuclear power unit (11) and the main power grid (6) is connected to two split transformers (12) respectively, and each split transformer (12) is connected to two independent medium-voltage DC systems (3) respectively, which are used to convert the AC power of the nuclear power unit (11) or the main power grid (6) into medium-voltage DC power and transmit it to the medium-voltage DC system (3). The nodes connected to the auxiliary power grid (7) are connected to the medium-voltage DC system (3) by connecting the second switch device (14) and the unidirectional AC-DC converter (13) in series. Each auxiliary power grid (7) is connected to two unidirectional AC-DC converters (13) and two different medium-voltage DC systems (3) to convert the AC power of the auxiliary power grid (7) into medium-voltage DC power and transmit it to the medium-voltage DC system (3).

5. A DC power supply and distribution system for a nuclear power plant oriented towards a computing data center, as described in claim 4, is characterized in that... The second switching device (14) includes a disconnecting switch and a circuit breaker. The disconnecting switch and the circuit breaker are connected in series and then connected to two disconnecting switches respectively.

6. A DC power supply and distribution system for a nuclear power plant oriented towards a computing data center, as described in claim 1, is characterized in that, The medium-voltage DC system (3) includes a first switching device (8), a second switching device (14), a standby diesel generator (15), a third switching device (16), a first bus (17), a unidirectional DC-AC converter (18), a DC energy storage system (19), and a medium-voltage VFD motor load (20). The first busbar (17) includes multiple individual busbars and a third switch device (16); wherein, every two busbars are connected by the third switch device (16) to form a double busbar segmented wiring structure; the first busbar (17) is connected to the second switch device (14) so ​​that when the busbar fails or is under maintenance, the operation of the remaining system can be restored through switching operation; The standby diesel generator (15) is connected to the first busbar (17) via a first switching device (8), a unidirectional AC-DC converter (13), and a second switching device (14) connected in series. The medium-voltage VFD motor load (20) is connected to the first busbar (17) via a first switching device (8), a unidirectional DC-AC converter (18), and a second switching device (14) connected in series. The DC energy storage system (19) is connected to the first bus (17) through the second switching device (14). The first bus (17) is connected to the first voltage conversion module (2) and the second voltage conversion module (4) respectively.

7. A DC power supply and distribution system for a nuclear power plant oriented towards a computing data center, as described in claim 1, characterized in that, The second voltage conversion module (4) includes a second switching device (14) and a unidirectional DC-DC converter (21). The medium-voltage DC system (3) is connected to the low-voltage DC system (5) via a second switching device (14) and a unidirectional DC-DC converter (21) connected in series. The second voltage conversion module (4) steps down the medium-voltage DC power of the medium-voltage DC system (3) and transmits the stepped-down medium-voltage DC power to the low-voltage DC system (5).

8. A DC power supply and distribution system for a nuclear power plant oriented towards a computing data center, as described in claim 1, characterized in that, The low-voltage DC system (5) includes a first switching device (8), a second switching device (14), a third switching device (16), a unidirectional DC-AC converter (18), a DC energy storage system (19), a second bus (22), an IT load (23), and a low-voltage VFD motor load (24). The second busbar (22) includes multiple busbars and a third switch device (16). Each pair of busbars is connected by the third switch device (16) to form a double busbar interconnection wiring structure. The second busbar (22) is connected to the second switchgear (14) so ​​that when the busbar fails or is under maintenance, the remaining system can be restored to operation through switching operations. The low-voltage VFD motor load (24) is connected to the second bus (22) via a first switching device (8), a unidirectional DC-AC converter (18), and a second switching device (14) connected in series. The unidirectional DC-AC converter (18) can convert the low-voltage DC power of the second bus (22) into low-voltage AC power and transmit it to the low-voltage VFD motor load (24). The DC energy storage system (19) is connected to the second bus (22) via the second switching device (14). The IT load (23) is connected to the second bus (22) through the second switching device (14); The second voltage conversion module (4) is connected to the second bus (22).

9. A DC power supply and distribution system for a nuclear power plant oriented towards a computing data center, as described in claim 1, characterized in that, The voltage level of the medium-voltage DC system (3) is 10kV or 20kV; the voltage level of the low-voltage DC system (5) is 800V or 1kV.

10. A method for operating a DC power supply and distribution system for a nuclear power plant oriented towards a computing data center, based on the DC power supply and distribution system for a nuclear power plant oriented towards a computing data center as described in any one of claims 1-9, characterized in that, include: The first voltage conversion module (2) converts the AC power of the main power system (1) into medium-voltage DC power and transmits the medium-voltage DC power to the medium-voltage DC system (3). The second voltage conversion module (4) is used to convert the medium-voltage DC power of the medium-voltage DC system (3) into low-voltage DC power and transmit the low-voltage DC power to the low-voltage DC system (5). During normal operation, the main power supply system (1) supplies power to the medium-voltage DC system (3) and the low-voltage DC system (5) respectively. When the main power system (1) fails, the first voltage conversion module (2) is disconnected, and the medium-voltage DC system (3) can supply power to the low-voltage DC system (5); When neither the main power system (1) nor the medium-voltage DC system (3) can supply power, the second voltage conversion module (4) is disconnected so that the low-voltage DC system (5) can meet its own load requirements.

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