Power distribution unit and energy storage system
By using high-voltage DC contactor sets to replace traditional AC contactors in energy storage systems, the system space layout problem caused by the large AC contactor size is solved, and higher space utilization and system stability are achieved.
Patent Information
- Application Number
- CN202421608229.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-09
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-07-09
AI Technical Summary
In traditional AC systems, the AC contactor used to control the on-off of the AC side of the AC side has a large volume, which increases the difficulty of system space layout, which is not conducive to the integrated design of the system.
A high-voltage DC contactor group is used to replace traditional AC contactors, and overcurrent protection and fault detection are carried out through the circuit breaker group and control unit to ensure the stability and reliability of the system.
The high-voltage DC contactor has a small size and better arc-breaking ability than the AC contactor, which improves the space utilization of the energy storage system, facilitates the integrated design of the system, and ensures the stability and reliability of the system.
Smart Images
Figure CN222801704U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of circuits, and in particular to a power distribution unit and an energy storage system. Background Art
[0002] In traditional AC systems, high-power electric energy is mainly disconnected and connected by AC contactors. However, the larger the current that the AC contactor disconnects, the larger its size will be. As industrial and commercial energy storage systems gradually develop towards high integration and large capacity, the requirements for space utilization and disconnection current levels are getting higher and higher. If AC contactors are continued to be used for disconnection control, it will increase the difficulty of system space layout and be detrimental to the integrated design of the system. Utility Model Content
[0003] The utility model provides a power distribution unit and an energy storage system, aiming to solve the problem in the related art that the AC contactor used for controlling the on and off of AC side electric energy is large in size and is not conducive to the integrated design of the system.
[0004] In order to solve the above technical problems, the first aspect of the utility model provides a power distribution unit, including: a circuit breaker group and a high-voltage DC contactor group; the first end of the circuit breaker group is electrically connected to the first end of the high-voltage DC contactor group, the second end of the circuit breaker group is used to be electrically connected to an external AC power grid, the third end of the circuit breaker group is used to be electrically connected to an external control unit, the second end of the high-voltage DC contactor group is used to be electrically connected to an external energy storage unit, the third end of the high-voltage DC contactor group is used to be electrically connected to an external DC power supply, and the fourth end of the high-voltage DC contactor group is used to be electrically connected to the control unit.
[0005] Furthermore, the circuit breaker group includes a first circuit breaker, a second circuit breaker and a third circuit breaker, the first ends of the first circuit breaker, the second circuit breaker and the third circuit breaker are respectively used to be electrically connected to the corresponding live wire of the AC power grid, the second ends of the first circuit breaker, the second circuit breaker and the third circuit breaker are all electrically connected to the high-voltage DC contactor group, and the third ends of the first circuit breaker, the second circuit breaker and the third circuit breaker are all used to be electrically connected to the control unit.
[0006] Further, the high-voltage DC contactor group includes a first high-voltage DC contactor, a second high-voltage DC contactor, a third high-voltage DC contactor and a fourth high-voltage DC contactor; the first ends of the first high-voltage DC contactor, the second high-voltage DC contactor and the third high-voltage DC contactor are respectively electrically connected to the corresponding circuit breakers, and the first end of the fourth high-voltage DC contactor is used to be electrically connected to the neutral line of the AC power grid; the second ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor are all used to be electrically connected to the energy storage unit; the third ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor are all used to be electrically connected to the DC power supply; the fourth ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor are all used to be electrically connected to the control unit.
[0007] The second aspect of the utility model provides an energy storage system, comprising a control unit, a DC power supply, an energy storage unit and the power distribution unit as described in the first aspect of the utility model; the first end of the circuit breaker group is electrically connected to the first end of the high-voltage DC contactor group, the second end of the circuit breaker group is used to be electrically connected to an external AC power grid, the third end of the circuit breaker group is electrically connected to the control unit, the second end of the high-voltage DC contactor group is electrically connected to the energy storage unit, the third end of the high-voltage DC contactor group is electrically connected to the DC power supply, and the fourth end of the high-voltage DC contactor group is electrically connected to the control unit.
[0008] From the above description, it can be seen that the utility model adopts a high-voltage DC contactor group to replace the AC contactor. The high-voltage DC contactor is not only small in size, but also superior to the AC contactor in the ability to break and extinguish arcs of AC power. Therefore, the power distribution unit can improve the space utilization of the energy storage system and facilitate the integrated design of the system; the on and off of the high-voltage DC contactor can be controlled by the DC power supply, and the control unit performs contactor fault detection, and overcurrent protection is performed through the circuit breaker group, thereby ensuring the stability and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 It is a structural schematic diagram of a power distribution unit according to an embodiment of the utility model;
[0010] Figure 2 It is a circuit schematic diagram of the first power distribution unit of the embodiment of the utility model;
[0011] Figure 3 This is a schematic diagram of contact point distribution of a high-voltage DC contactor according to an embodiment of the utility model;
[0012] Figure 4 It is a circuit schematic diagram of a second power distribution unit of an embodiment of the utility model;
[0013] Figure 5 It is a structural schematic diagram of an energy storage system according to an embodiment of the utility model. DETAILED DESCRIPTION
[0014] In order to make the purpose, technical scheme and advantages of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model. In addition, the technical features involved in the various embodiments of the utility model described below can be combined with each other as long as they do not conflict with each other.
[0015] In the related art, since the AC contactor used to control the disconnection of AC power is relatively large, it is not conducive to the integrated design of the system. Therefore, an embodiment of the utility model provides a power distribution unit.
[0016] like Figure 1 The figure shows a structural schematic diagram of a power distribution unit provided by an embodiment of the utility model, and the power distribution unit includes: a circuit breaker group 100 and a high-voltage DC contactor group 200; a first end of the circuit breaker group 100 is electrically connected to a first end of the high-voltage DC contactor group 200, a second end of the circuit breaker group 100 is used to be electrically connected to an external AC power grid 300, a third end of the circuit breaker group 100 is used to be electrically connected to an external control unit 400, a second end of the high-voltage DC contactor group 200 is used to be electrically connected to an external energy storage unit 500, a third end of the high-voltage DC contactor group 200 is used to be electrically connected to an external DC power supply 600, and a fourth end of the high-voltage DC contactor group 200 is used to be electrically connected to the control unit 400.
[0017] Specifically, the power distribution unit (PDU) in this embodiment can be used to distribute AC power to the energy storage unit 500, which uses a high-voltage DC contactor to replace the AC contactor in the traditional AC side system. The high-voltage DC contactor can use a non-polar high-voltage DC contactor, and compared with the AC contactor, it is smaller in size and has better AC current breaking and arc extinguishing capabilities, thereby improving the space utilization of the system and facilitating the modular design of the system. The DC power supply 600 then controls the on-off of the DC contactor, so that multiple DC contactors can be disconnected synchronously. At the same time, the control unit 400 detects the fault information of the DC contactor, and the circuit breaker performs overcurrent protection, thereby ensuring the stability and reliability of the system.
[0018] like Figure 2 The circuit diagram of the first power distribution unit provided in this embodiment is shown in FIG. Figure 2 The circuit breaker group 100 includes a first circuit breaker K1, a second circuit breaker K2 and a third circuit breaker K3. The first ends of the first circuit breaker K1, the second circuit breaker K2 and the third circuit breaker K3 are respectively used to be electrically connected to the live wire of the corresponding AC power grid 300. The second ends of the first circuit breaker K1, the second circuit breaker K2 and the third circuit breaker K3 are all electrically connected to the high-voltage DC contactor group 200. The third ends of the first circuit breaker K1, the second circuit breaker K2 and the third circuit breaker K3 are all used to be electrically connected to the control unit 400.
[0019] For further information, see Figure 2 The high-voltage DC contactor group 200 includes a first high-voltage DC contactor KMD1, a second high-voltage DC contactor KMD2, a third high-voltage DC contactor KMD3 and a fourth high-voltage DC contactor KMD4; the first ends 1 of the first high-voltage DC contactor KMD1, the second high-voltage DC contactor KMD2 and the third high-voltage DC contactor KMD3 are respectively electrically connected to the corresponding circuit breakers, and the first end 1 of the fourth high-voltage DC contactor KMD4 is used to be electrically connected to the neutral line of the AC power grid 300; the first high-voltage DC contactor KMD1, the second high-voltage DC contactor KMD2, the third high-voltage DC contactor KMD3 The second ends 2 of the contactor KMD3 and the fourth high-voltage DC contactor KMD4 are both used to be electrically connected to the energy storage unit 500; the third ends 3 (4) of the first high-voltage DC contactor KMD1, the second high-voltage DC contactor KMD2, the third high-voltage DC contactor KMD3 and the fourth high-voltage DC contactor KMD4 are both used to be electrically connected to the DC power supply 600; the fourth ends 5 (6) of the first high-voltage DC contactor KMD1, the second high-voltage DC contactor KMD2, the third high-voltage DC contactor KMD3 and the fourth high-voltage DC contactor KMD4 are all used to be electrically connected to the control unit 400.
[0020] Further, see Figure 2 The third ends of the first high-voltage DC contactor KMD1, the second high-voltage DC contactor KMD2, the third high-voltage DC contactor KMD3 and the fourth high-voltage DC contactor KMD4 all include a first sub-terminal 3 and a second sub-terminal 4. The first sub-terminal 3 of the first high-voltage DC contactor KMD1, the second high-voltage DC contactor KMD2, the third high-voltage DC contactor KMD3 and the fourth high-voltage DC contactor KMD4 is used to be electrically connected to the positive pole of the DC power supply 600, and the second sub-terminal 4 of the first high-voltage DC contactor KMD1, the second high-voltage DC contactor KMD2, the third high-voltage DC contactor KMD3 and the fourth high-voltage DC contactor KMD4 is used to be electrically connected to the negative pole of the DC power supply 600.
[0021] The fourth ends of the first high-voltage DC contactor KMD1, the second high-voltage DC contactor KMD2, the third high-voltage DC contactor KMD3 and the fourth high-voltage DC contactor KMD4 all include a third sub-terminal 5 and a fourth sub-terminal 6; the third sub-terminal 5 of the first high-voltage DC contactor KMD1 is used to be electrically connected to the control unit 400, the fourth sub-terminal 6 of the first high-voltage DC contactor KMD1 is electrically connected to the fourth sub-terminal 6 of the second high-voltage DC contactor KMD2, the third sub-terminal 5 of the second high-voltage DC contactor KMD2 is electrically connected to the third sub-terminal 5 of the third high-voltage DC contactor KMD3, the fourth sub-terminal 6 of the third high-voltage DC contactor KMD3 is electrically connected to the fourth sub-terminal 6 of the fourth high-voltage DC contactor KMD4, and the fourth sub-terminal 6 of the fourth high-voltage DC contactor KMD4 is used to be electrically connected to the control unit 400. Or, the fourth sub-terminal 6 of the first high-voltage DC contactor KMD1 is used to be electrically connected to the control unit 400, the third sub-terminal 5 of the first high-voltage DC contactor KMD1 is electrically connected to the third sub-terminal 5 of the second high-voltage DC contactor KMD2, the fourth sub-terminal 6 of the second high-voltage DC contactor KMD2 is electrically connected to the fourth sub-terminal 6 of the third high-voltage DC contactor KMD3, the third sub-terminal 5 of the third high-voltage DC contactor KMD3 is electrically connected to the third sub-terminal 5 of the fourth high-voltage DC contactor KMD4, and the third sub-terminal 5 of the fourth high-voltage DC contactor KMD4 is used to be electrically connected to the control unit 400.
[0022] Specifically, in this embodiment, when the power distribution unit performs three-phase five-wire AC power supply, the circuit breaker group 100 may be composed of three circuit breakers, and the three circuit breakers are respectively connected to the corresponding live wires. The circuit breakers can effectively prevent circuit overload, short circuit and other faults to ensure the stability and reliability of the system, and the circuit breaker is connected to the control unit 400 to improve the flexibility of control. The control unit 400 can be a microcontroller MCU and a digital signal processor DSP. The high-voltage DC contactor group 200 can be composed of four non-polar high-voltage DC contactors to replace the traditional 4P AC contactor, wherein the distribution diagram of each contact point of the high-voltage DC contactor is as shown in FIG. Figure 3As shown, the first end and the second end of the four high-voltage DC contactors are respectively connected to the circuit breaker and the energy storage unit 500, which are the main circuit contact point 10; the third ends of the four high-voltage DC contactors are used to connect to the DC power supply 600 (for example, a 24V power supply), which is the control circuit contact point 20. The four high-voltage DC contactors use the same DC power supply 600, and the power supply is connected in parallel. When the AC main circuit is turned on and off, the DC power supply 600 is disconnected or connected at the same time, which can ensure that the four phases are disconnected or connected synchronously; the fourth ends of the four high-voltage DC contactors are used to connect to the control unit 400, which is the feedback circuit contact point 30, so as to detect the fault information of each DC contactor, wherein the fourth end of each high-voltage DC contactor, that is, the feedback signal end, is connected in series, and when any contactor fails, the control unit 400 can identify it.
[0023] like Figure 4 The circuit diagram of the second power distribution unit provided in this embodiment is shown in FIG. Figure 4 The power distribution unit further includes a fuse group, one end of which is electrically connected to the AC power grid 300 and the other end of which is electrically connected to the circuit breaker group 100 .
[0024] Specifically, the fuse group includes a first fuse F1, a second fuse F2 and a third fuse F3, one end of the first fuse F1, the second fuse F2 and the third fuse F3 are respectively used to be electrically connected to the live wire of the corresponding AC power grid 300, and the other ends of the first fuse F1, the second fuse F2 and the third fuse F3 are respectively electrically connected to the corresponding circuit breaker. In this embodiment, a fuse is also provided on the basis of the circuit breaker to play the role of short circuit protection and overload protection. When the current exceeds the rated value of the fuse, the fuse will melt and cut off the circuit. If the current is lower than the rated value of the fuse but exceeds the rated value of the circuit breaker, the circuit breaker will play the role of overload protection and cut off the circuit. Therefore, the circuit breaker and the fuse work together to provide more comprehensive circuit protection.
[0025] like Figure 5 The structure diagram of an energy storage system provided by this embodiment is shown in FIG. Figure 5 The energy storage system includes a control unit 400, a DC power supply 600, an energy storage unit 500 and the above-mentioned power distribution unit. Among them, the first end of the circuit breaker group 100 is electrically connected to the first end of the high-voltage DC contactor group 200, the second end of the circuit breaker group 100 is used to be electrically connected to the external AC power grid 300, the third end of the circuit breaker group 100 is electrically connected to the control unit 400, the second end of the high-voltage DC contactor group 200 is electrically connected to the energy storage unit 500, the third end of the high-voltage DC contactor group 200 is electrically connected to the DC power supply 600, and the fourth end of the high-voltage DC contactor group 200 is electrically connected to the control unit 400.
[0026] For further information, see Figure 5 The energy storage system further includes a relay RLY, which is electrically connected to the common connection terminals of the control unit 400, the DC power supply 600 and the high-voltage DC contactor group 200 respectively.
[0027] Further, see Figure 5 The energy storage unit includes an energy storage converter 510 and a battery pack 520 . The energy storage converter 510 is electrically connected to the high-voltage DC contactor group 200 and the battery pack 520 , respectively.
[0028] Specifically, in the present embodiment, the energy storage system further includes a relay RLY, the energy storage unit includes an energy storage converter (PCS) and a battery pack, the relay RLY is connected between the positive pole of the DC power supply 600 and the high-voltage direct contactor, and is connected to the control unit 400, so that the on and off of the relay RLY can be controlled by the control unit 400, thereby controlling the on and off of the AC circuit; the PCS module is used to convert DC power into DC power, so as to transmit the DC power to the battery pack 520.
[0029] The power distribution unit provided in the embodiment of the utility model adopts a high-voltage DC contactor group to replace the AC contactor. The high-voltage DC contactor is not only small in size, but also has better arc-extinguishing ability than the AC contactor. Therefore, the power distribution unit can improve the space utilization rate of the energy storage system and facilitate the integrated design of the system. The on and off of the high-voltage DC contactor can be controlled by the DC power supply, and the control unit performs contactor fault detection and performs overcurrent protection through the circuit breaker group, thereby ensuring the stability and reliability of the system.
[0030] It should be noted that the various embodiments in the present invention are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referenced to each other.
[0031] It should also be noted that, in the present invention, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.
[0032] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined in the present invention may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in the present invention, but will conform to the widest range consistent with the principles and novel features disclosed in the present invention.
Claims
1. A power distribution unit, characterized in that: include: A circuit breaker group and a high-voltage DC contactor group; a first end of the circuit breaker group is electrically connected to a first end of the high-voltage DC contactor group, a second end of the circuit breaker group is used to be electrically connected to an external AC power grid, a third end of the circuit breaker group is used to be electrically connected to an external control unit, a second end of the high-voltage DC contactor group is used to be electrically connected to an external energy storage unit, a third end of the high-voltage DC contactor group is used to be electrically connected to an external DC power supply, and a fourth end of the high-voltage DC contactor group is used to be electrically connected to the control unit.
2. The power distribution unit according to claim 1, characterized in that: The circuit breaker group includes a first circuit breaker, a second circuit breaker and a third circuit breaker, wherein the first ends of the first circuit breaker, the second circuit breaker and the third circuit breaker are respectively used to be electrically connected to the corresponding live wire of the AC power grid, the second ends of the first circuit breaker, the second circuit breaker and the third circuit breaker are all electrically connected to the high-voltage DC contactor group, and the third ends of the first circuit breaker, the second circuit breaker and the third circuit breaker are all used to be electrically connected to the control unit.
3. The power distribution unit according to claim 2, characterized in that: The high-voltage DC contactor group includes a first high-voltage DC contactor, a second high-voltage DC contactor, a third high-voltage DC contactor and a fourth high-voltage DC contactor; The first ends of the first high-voltage DC contactor, the second high-voltage DC contactor and the third high-voltage DC contactor are respectively electrically connected to the corresponding circuit breakers, and the first end of the fourth high-voltage DC contactor is used to be electrically connected to the neutral line of the AC power grid; the second ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor are all used to be electrically connected to the energy storage unit; the third ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor are all used to be electrically connected to the DC power supply; the fourth ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor are all used to be electrically connected to the control unit.
4. The power distribution unit according to claim 3, characterized in that: The third ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor all include a first sub-end and a second sub-end, and the first sub-ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor are all used to be electrically connected to the positive pole of the DC power supply, and the second sub-ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor are all used to be electrically connected to the negative pole of the DC power supply.
5. The power distribution unit according to claim 3, characterized in that: The fourth ends of the first high-voltage DC contactor, the second high-voltage DC contactor, the third high-voltage DC contactor and the fourth high-voltage DC contactor all include a third sub-end and a fourth sub-end; The third sub-terminal of the first high-voltage DC contactor is used to be electrically connected to the control unit, the fourth sub-terminal of the first high-voltage DC contactor is electrically connected to the fourth sub-terminal of the second high-voltage DC contactor, the third sub-terminal of the second high-voltage DC contactor is electrically connected to the third sub-terminal of the third high-voltage DC contactor, the fourth sub-terminal of the third high-voltage DC contactor is electrically connected to the fourth sub-terminal of the fourth high-voltage DC contactor, and the fourth sub-terminal of the fourth high-voltage DC contactor is used to be electrically connected to the control unit.
6. The power distribution unit according to claim 1, characterized in that: It also includes a fuse group, one end of which is used to be electrically connected to the AC power grid, and the other end of which is electrically connected to the circuit breaker group.
7. The power distribution unit according to claim 6, characterized in that: The fuse group includes a first fuse, a second fuse and a third fuse, one end of the first fuse, the second fuse and the third fuse are respectively used to be electrically connected to the corresponding live wire of the AC power grid, and the other ends of the first fuse, the second fuse and the third fuse are respectively electrically connected to the corresponding circuit breaker.
8. An energy storage system, characterized in that: It comprises a control unit, a DC power supply, an energy storage unit and a power distribution unit as claimed in any one of claims 1 to 7; The first end of the circuit breaker group is electrically connected to the first end of the high-voltage DC contactor group, the second end of the circuit breaker group is used to be electrically connected to an external AC power grid, the third end of the circuit breaker group is electrically connected to the control unit, the second end of the high-voltage DC contactor group is electrically connected to the energy storage unit, the third end of the high-voltage DC contactor group is electrically connected to the DC power supply, and the fourth end of the high-voltage DC contactor group is electrically connected to the control unit.
9. The energy storage system according to claim 8, characterized in that: It also includes a relay, which is electrically connected to the control unit, the DC power supply and the common connection end of the high-voltage DC contactor group respectively.
10. The energy storage system according to claim 8, characterized in that: The energy storage unit includes an energy storage converter and a battery pack. The energy storage converter is electrically connected to the high-voltage DC contactor group and the battery pack respectively.