Valve assembly, power module, energy storage sub-module, and energy storage system

Abstract

The present application relates to a valve assembly, a power module, an energy storage sub-module, and an energy storage system. The valve assembly comprises a power device, a cooling member, an impedance device and a press-fitting structure; the press-fitting structure is provided with a press-fitting space; the power device, the cooling member and the impedance device are arranged in the press-fitting space; and the power device is electrically connected to the impedance device. The power device, the cooling member and the impedance device are all press-fitted in the press-fitting space of the press-fitting structure, such that the distance between the power device and the impedance device can be shortened, and the distance for achieving electrical connection between the power device and the impedance device is shortened, reducing the electrical loss; and because the impedance device is press-fitted in the press-fitting structure, the installation space and the wiring space of the impedance device are also saved.

Description

Valve Assembly, Power Module, Energy Storage Sub-module and Energy Storage System Cross-reference This application claims priority to Chinese Patent Application No. 202311735952.3, titled "Valve Assembly, Power Module, Energy Storage Sub-module and Energy Storage System", filed on December 15, 2023, which is hereby incorporated by reference in its entirety into this application. Technical Field This application relates to the field of energy storage technologies, and particularly to a valve assembly, a power module, an energy storage sub-module and an energy storage system. Background Art With the development of large-scale energy storage, high-voltage energy storage valves have gradually been widely used. One end of a high-voltage energy storage valve is usually connected to the power grid through a converter valve, and the other end is connected to a battery through an energy storage valve power module. Through the switching control of power devices, the input and cut-off of energy storage valve sub-modules are realized, so as to charge the battery when the power grid has excess energy and discharge the battery to supplement the power grid when the power grid is short of energy. However, in some cases, there are quite a few impedance devices in the power module. When these impedance devices need to be connected to power devices, there is a problem of a large electrical connection distance. Summary of the Invention In view of the problems, this application provides a valve assembly, a power module, an energy storage sub-module and an energy storage system, which can alleviate the problem of a large electrical connection distance between impedance devices and power devices. In a first aspect, this application provides a valve assembly, including a power device, a cooling component, an impedance device and a press-fitting structure. The press-fitting structure has a press-fitting space, and the power device, the cooling component and the impedance device are arranged in the press-fitting space, and the power device and the impedance device are electrically connected. In the above valve assembly, by simultaneously press-fitting the power device, the cooling component and the impedance device in the press-fitting space of the press-fitting structure, the distance between the power device and the impedance device can be shortened, so that the electrical connection distance between the power device and the impedance device is shorter, reducing electrical losses. And since the impedance device is press-fitted in the press-fitting structure, the installation space and wiring space of the impedance device are also saved. In some embodiments, the power device, the cooling component and the impedance device are arranged along a preset direction, and each power device and impedance device is adjacent to at least one cooling component. Since each power device and impedance device is adjacent to at least one cooling component, each power device and impedance device can be cooled by the cooling component to achieve heat dissipation and cooling, thus improving the operating reliability of the power device and the impedance device during operation. In some embodiments, the impedance device and the power device are arranged between the same two adjacent cooling components. A cooling space can be formed between any two adjacent cooling components, and the devices placed in this cooling space can obtain a better cooling effect. In some embodiments, the impedance device and the power device are respectively disposed between two adjacent cooling members. A cooling space can be formed between any two adjacent cooling members, and the devices placed in the cooling space can obtain better cooling effects. In some embodiments, there are multiple power devices, and the multiple power devices and the cooling members are alternately arranged along a preset direction. In this way, any power device can be cooled by the cooling member to achieve heat dissipation and cooling, improving the heat dissipation efficiency and effect. In some embodiments, the power device includes an IGBT or a unidirectional conduction tube. The valve assembly includes two IGBTs and two unidirectional conduction tubes, and each IGBT and each unidirectional conduction tube are alternately arranged along a preset direction. In this way, each IGBT is disposed between two adjacent cooling members, and each unidirectional conduction tube is disposed between another two adjacent cooling members. Each IGBT and unidirectional conduction tube of the power device can be cooled by the cooling member to achieve heat dissipation and cooling, improving the heat dissipation efficiency and effect. In some embodiments, the power device and the impedance device have a contact conductive surface. By setting that the power device and the impedance device have a contact conductive surface, the power device and the impedance device can be in direct contact conduction with the conductive device, simplifying the electrical connection relationship between the power device and the impedance device and the conductive device. Compared with traditional copper busbars or cable connections, a large amount of space and cost can be saved. In some embodiments, the impedance device is flat, and the contact conductive surface is located on the flat surface of the impedance device. The flat impedance device has a larger flat surface area, making the area of the contact conductive surface larger and improving the stability of the electrical connection between the impedance device and the conductive device. In some embodiments, the cooling member is a conductive cooling member, and the contact conductive surfaces of the power device and the impedance device are in contact with the cooling member to achieve electrical connection. By setting the cooling member as a conductive cooling member, and making the contact conductive surfaces of the power device and the impedance device in contact with the cooling member to achieve electrical connection, the electrical connection relationship between the power devices and between the power device and the impedance device can be simplified. Compared with traditional copper busbars or cable connections, a large amount of space and cost can be saved. And since the devices in the valve assembly are connected together by press-fitting, the reliability of the electrical connection is improved. In some embodiments, the impedance device and the power device are in a disc shape, and the absolute value of the difference between the diameter of the impedance device and the diameter of the power device is not greater than 10% of the diameter of the power device. By setting the absolute value of the difference between the diameter of the impedance device and the diameter of the power device to be no greater than 10% of the diameter of the power device, the diameter of the impedance device can be made close to that of the power device. As a result, the pressing force between the devices is more uniform during press-fitting, improving the press-fitting stability during the press-fitting process. Furthermore, the electrical connection reliability between the contact conductive surface of the impedance device and the power device and the cooling component is enhanced. In some embodiments, the valve assembly further includes at least one positioning member, and at least one positioning member is disposed between the impedance device and the cooling component. By providing the positioning member, the stability of the positional relationship between the impedance device and the cooling component can be improved, thereby enhancing the reliability of press-fitting and the electrical connection reliability between the impedance device and the cooling component. In a second aspect, a power module is further provided, and the power module includes the valve assembly in any of the above embodiments. In the above power module, by press-fitting the power device, the cooling component, and the impedance device into the press-fitting space of the press-fitting structure simultaneously, the distance between the power device and the impedance device can be shortened. As a result, the distance for the power device and the impedance device to achieve electrical connection is shorter, reducing the electrical loss. Moreover, since the impedance device is press-fitted into the press-fitting structure, the installation space and wiring space of the impedance device are also saved. In some embodiments, the impedance device includes a resistor. By providing the resistance value required by the resistance element to suppress the underdamped oscillating current generated at the moment of energizing the energy storage valve sub-module, it is not only highly economical but also convenient and simple to use, greatly reducing the additional impact on the overall function of the energy storage valve sub-module. In some embodiments, when the power device, the cooling component, and the impedance device are arranged in a preset direction, the impedance device and the power device are respectively disposed between two adjacent cooling components, and the power device and the impedance device have contact conductive surfaces. When the cooling component is a conductive cooling component and the contact conductive surfaces of the power device and the impedance device are in contact with the cooling component to achieve electrical connection; The power module further includes a first laminated busbar and a first capacitor. The first laminated busbar is disposed on one side of all the cooling components and is electrically connected to some of the cooling components. The first capacitor is connected in series with the cooling component adjacent to the impedance device through the first laminated busbar to form a resistor-capacitor branch; the power device and the cooling component adjacent to the power device form a DC output side, and the resistor-capacitor branch is connected in parallel with the DC output side through the first laminated busbar.

[0100] Since the impedance device can adjust the resistance value of the impedance in the energy storage valve sub-module to suppress the energy storage valve sub-module The underdamped oscillating current generated at the moment of switching the switching state is thus greatly reduced, achieving the effect of suppressing the underdamped oscillating current, significantly reducing the harm brought by the underdamped oscillating current to the energy storage valve sub-module, and thus improving the reliability of the energy storage valve sub-module. Additionally, while electrically connecting the adjacent cooling part of the impedance device and the first capacitor through the first laminated busbar, the resistive-capacitive branch and the DC output side are also electrically connected. Therefore, the connection lines between the impedance device, the first capacitor, and the power device can be made simpler through the first laminated busbar, reducing the loop resistance and loop stray inductance. In some embodiments, the power module further includes a second capacitor, and the capacitance of the second capacitor is smaller than that of the first capacitor. The power module further includes a second laminated busbar. The second capacitor is connected in parallel with the DC output side through the second laminated busbar and is connected in parallel with the resistive-capacitive branch through the first laminated busbar; or the second capacitor is connected in parallel with the DC output side through the first laminated busbar and is connected in parallel with the resistive-capacitive branch.

[0101] By integrally connecting a second capacitor in parallel beside the resistive-capacitive branch, the overvoltage at the moment of power device turn-off can be reduced. The stress is reduced, and the risk of power device failure due to excessive overvoltage stress is reduced, thereby increasing the working reliability of the power device and further increasing the working reliability of the energy storage valve sub-module. Additionally, setting the second capacitor to be connected in parallel with the DC output side through the first laminated busbar simplifies the connection lines between the second capacitor, the power device, and the resistive-capacitive branch. Setting the second laminated busbar to electrically connect the DC output side and the second capacitor makes the connection line simpler, reducing the loop resistance and loop stray inductance. In a third aspect, an energy storage valve sub-module is provided, including the power module in any of the above embodiments. In the above energy storage valve sub-module, by simultaneously pressing the power device, the cooling part, and the impedance device into the pressing space of the pressing structure, the distance between the power device and the impedance device can be shortened, thereby making the distance for the power device and the impedance device to achieve electrical connection shorter, reducing the electrical loss, and since the impedance device is pressed into the pressing structure, the installation space and wiring space of the impedance device are also saved. In a fourth aspect, an energy storage system is provided, including the energy storage valve sub-module in any of the above embodiments. In the above energy storage system, by simultaneously pressing the power device, the cooling part, and the impedance device into the pressing space of the pressing structure, the distance between the power device and the impedance device can be shortened, thereby making the distance for the power device and the impedance device to achieve electrical connection shorter, reducing the electrical loss, and since the impedance device is pressed into the pressing structure, the installation space and wiring space of the impedance device are also saved. The above description is only an overview of the technical solution of this application. In order to understand the technical means of this application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of this application more obvious and understandable, the following specific embodiments of this application are specifically given. Brief Description of the Drawings In order to more clearly illustrate the technical solutions of the embodiments of this application, the drawings required to be used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings. In the drawings: FIG. 1 is a schematic structural diagram of a valve assembly in one or more embodiments. FIG. 2 is a schematic structural diagram of an impedance device in one or more embodiments. FIG. 3 is a schematic structural diagram of a power module in another or more embodiments. FIG. 4 is a schematic structural diagram of a partial structure of the power module shown in FIG. 3. FIG. 5 is a topological schematic diagram of a energy storage valve sub-module in the related art. FIG. 6 is a schematic diagram of the equivalent stray inductance and equivalent internal resistance of the energy storage unit in the energy storage valve sub-module shown in FIG. 5. FIG. 7 is a topological schematic diagram of an energy storage valve sub-module in one or more embodiments. FIG. 8 is a topological schematic diagram of an energy storage valve sub-module in another or more embodiments. FIG. 9 is a schematic structural diagram of a power module in another or more embodiments. FIG. 10 is a schematic structural diagram of a power module in yet another or more embodiments. FIG. 11 is a schematic structural diagram of another perspective of the power module shown in FIG. 10. FIG. 12 is a schematic structural diagram of a partial structure of another perspective of the power module shown in FIG. 10. FIG. 13 is a schematic structural diagram of another perspective of the power module shown in FIG. 10. Reference Numerals: Valve assembly 100; First side 101, second side 102, third side 103, fourth side 104, fifth side 105; Power device 10, cooling member 20; Impedance device 30, contact conductive surface 31, pin hole 32; Press-fitting structure 40, first press-fitting assembly 41, frame plate 411, equalizing plate 412, insulating block 413, second press-fitting assembly 42, connection assembly 43, pull rod 431; First stacked busbar 50; DC busbar 55; AC busbar 60; First capacitor 65, end face 651; Second capacitor 70; Second laminated busbar 75; Bypass switch 78; Adapter busbar 80; Power supply 85; Inlet and outlet water pipes 88; Explosion-proof insulating part 90; Flow guide box 95 Power module 200. Specific implementation mode Hereinafter, embodiments of the technical solution of the present application will be described in detail with reference to the drawings. The following embodiments are only used to illustrate the technical solution of the present application more clearly, so they are only examples and cannot be used to limit the protection scope of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion. In the description of the embodiments of this application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of this application, "a plurality" means more than two, unless otherwise specifically defined. Referring to "embodiment" herein means that the specific features, structures or characteristics described in connection with the embodiment may be included in at least one embodiment of this application. The phrase appears in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments. In the description of the embodiments of this application, the term " / and" is only a description of the association relationship of the associated objects, indicating that three relationships may exist. For example, 1 and / or 2 may mean: 1 exists alone, 1 and 2 exist simultaneously, and 2 exists alone. In addition, the character " / " herein generally means that the front and rear associated objects are in an "or" relationship. In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two). Similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to two or more pieces (including two pieces). In the description of the embodiments of the present application, the orientation or positional relationship indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation on the embodiments of the present application. In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific situations. As shown in FIG. 1, FIG. 1 is a schematic structural diagram of a valve assembly according to one or more embodiments. Referring to the drawings, an embodiment of the present application provides a valve assembly 100. The valve assembly 100 includes a power device 10, a cooling member 20, an impedance device 30, and a press-fitting structure 40. The press-fitting structure 40 has a press-fitting space AA, and the power device 10, the cooling member 20, and the impedance device 30 are disposed in the press-fitting space AA, and the power device 10 and the impedance device 30 are electrically connected. The valve assembly 100 in the embodiments of the present application is a part of the energy storage valve sub-module, specifically a part of the power module 200. The energy storage valve sub-module can be applied to a high-voltage direct-connected energy storage system. Each energy storage valve sub-module further includes an energy storage unit, and the energy storage unit includes a battery pack. In practical applications, a plurality of energy storage valve sub-modules are cascaded in the high-voltage direct-connected energy storage system, and the charging and discharging of the energy storage units in each energy storage valve sub-module can be realized by controlling the cascaded energy storage valve sub-modules. The power device 10 is also called a power semiconductor device. The power device 10 can form a half-bridge circuit or a full-bridge circuit, etc. in the energy storage valve sub-module to form a power conversion unit in the energy storage valve sub-module. The main function of the power change unit is to realize the two working modes of the energy storage unit being put into and cut off in the charging and discharging states through different paths. Specifically, the power device 10 can include one of a unidirectional conduction tube, an IGBT device, or a thyristor. In some embodiments, the power device 10 can be discrete or integrated, and the number of power devices 10 can be one or more. When the power device 10 is connected to the impedance device 30 in the electrical topology, by pressing the power device 10 and the impedance device 30 together, a high-reliability connection is achieved, and it is beneficial to reduce the device size. The cooling member 20 refers to a device that can achieve a cooling effect on external components. The cooling method of the cooling member 20 can generally be water cooling, or it can also be air cooling, air blast cooling, or other cooling methods. Specifically, the cooling member 20 can include a cooling plate, and the cooling plate has a larger area and better heat dissipation effect. The impedance device 30 can be any device with a resistance value. Specifically, it can be a resistor, or some other passive devices containing resistance values, such as inductors. The press-fit structure 40 can be in the form of an assembly formed by multiple components, which can apply pressure to the power device 10, the cooling member 20, and the impedance device 30, so that there is a close relationship between the power device 10, the cooling member 20, and the impedance device 30. This close relationship can be a contact relationship, specifically, it can be the contact relationship between the contact conductive surface and the cooling member 20, or between the contact conductive surfaces, or it can also be a close spacing relationship. Press-fitting the power device can improve the connection reliability and good heat dissipation performance, and is suitable for the operating environment of high current and high power in the power system. The press-fit space AA is formed by the press-fit structure 40. When the power device 10, the cooling member 20, and the impedance device 30 are arranged in the press-fit space AA, they can be pressed by the press-fit structure 40. That is to say, when the power device 10, the cooling member 20, and the impedance device 30 are arranged outside the press-fit space AA, the pressure of the press-fit structure 40 may not reach the devices, resulting in press-fit failure. Therefore, for the valve assembly 100 of the present application, by pressing the power device 10, the cooling member 20, and the impedance device 30 into the press-fit space AA of the press-fit structure 40 at the same time, the distance between the power device 10 and the impedance device 30 can be shortened, and further the distance for the electrical connection between the power device 10 and the impedance device 30 can be made shorter, reducing the electrical loss. And since the impedance device 30 is press-fitted in the press-fit structure 40, the installation space and wiring space of the impedance device 30 are also saved. Please continue to refer to FIG. 1. According to some embodiments of the present application, the power device 10, the cooling member 20, and the impedance device 30 are arranged along a preset direction, and each power device 10 and impedance device 30 is adjacent to at least one cooling member 20. The preset direction referred to here can be the Z direction shown in FIG. 1. Specifically, after the valve assembly 100 is installed, the preset direction can be the vertical direction. Of course, the preset direction is not limited to the Z direction and the vertical direction, and can also be other directions or the horizontal direction. In an embodiment of the present application, the preset direction is also the direction in which the press-fitting structure 40 applies pressure to the power device 10, the cooling member 20, and the impedance device 30. Adjacency means that two objects are adjacent to each other and connected, and can also be referred to as being in close contact. That is, the power device 10 is adjacent to and connected to at least one cooling member 20, and the impedance device 30 is adjacent to and connected to at least one cooling member 20. Since each power device 10 and impedance device 30 is adjacent to at least one cooling member 20, each power device 10 and impedance device 30 can be cooled by the cooling member 20 to achieve heat dissipation and cooling, thus improving the operating reliability of the power device 10 and impedance device 30 during operation. Specifically, in the embodiment of the present application, the impedance device 30 and the power device 10 are disposed between the same two adjacent cooling members 20; and / or the impedance device 30 and the power device 10 are respectively disposed between two different adjacent cooling members 20. A cooling space can be formed between any two adjacent cooling members 20, and the devices placed in this cooling space can obtain a better cooling effect. In the embodiment of the present application, the cooling members 20 are arranged at intervals along the preset direction. Specifically, the impedance device 30 and the power device 10 are disposed between the same two adjacent cooling members 20, that is, without increasing the cooling members 20, the impedance device 30 and the power device 10 share the cooling members 20. In another embodiment, the impedance device 30 and the power device 10 are respectively disposed between two different adjacent cooling members 20. Therefore, the impedance device 30 can be independently disposed between two adjacent cooling members 20, and the power device 10 can also be independently disposed between other two adjacent cooling members 20. In still another embodiment, when there are multiple impedance devices 30, at least one impedance device 30 can be disposed between the same two adjacent cooling members 20 as at least one power device 10, and at least another impedance device 30 is disposed between the remaining two different adjacent cooling members 20. When there are multiple power devices 10, at least one power device 10 can be disposed between the same two adjacent cooling members 20 as at least one impedance device 30, and at least another power device 10 is disposed between the remaining two different adjacent cooling members 20. In summary, for the valve assembly 100 of the embodiment of the present application, regardless of where the impedance device 30 and the power device 10 are specifically disposed, both sides thereof are adjacent to the cooling member 20, and thus the impedance device 30 and the power device 10 can be more efficiently cooled by the cooling member 20. In some embodiments, when the impedance device 30 and the power device 10 are disposed between the same two adjacent cooling members 20, the impedance device 30 can be arranged side by side with the power device 10, or stacked, or offset. When the impedance device 30 and the power device 10 are arranged between two adjacent cooling components 20, the impedance device 30 can be arranged between two adjacent cooling components 20 at one end of all the power devices 10 along a preset direction, or can be arranged alternately between two adjacent cooling components 20 between two adjacent power devices 10. Furthermore, there are multiple power devices 10, and the multiple power devices 10 and the cooling components 20 are alternately arranged along a preset direction. In this way, any power device 10 can be cooled by the cooling component 20 to achieve heat dissipation and cooling, improving the heat dissipation efficiency and effect. Even further, the power device 10 includes an IGBT or a unidirectional conduction tube, the valve assembly 100 includes two IGBTs and two unidirectional conduction tubes, and each IGBT and each unidirectional conduction tube are alternately arranged along a preset direction. In this way, each IGBT is arranged between two adjacent cooling components 20, each unidirectional conduction tube is arranged between another two adjacent cooling components 20, and each IGBT and unidirectional conduction tube of the power device 10 can be cooled by the cooling component 20 to achieve heat dissipation and cooling, improving the heat dissipation efficiency and effect. In other embodiments, the valve assembly 100 can also include four IGBTs and four unidirectional conduction tubes, and each IGBT and each unidirectional conduction tube are alternately arranged along a preset direction. In the embodiments of the present application, the press-fitting structure 40 includes a first press-fitting component 41, a second press-fitting component 42 and a connecting component 43. The first press-fitting component 41 and the second press-fitting component 42 are arranged opposite to each other and form a press-fitting space AA. The connecting component 43 connects the first press-fitting component 41 and the second press-fitting component 42 to generate a pressing force for pressing the power device 10, the cooling component 20 and the impedance device 30 between the first press-fitting component 41 and the second press-fitting component 42. The press-fitting component is formed by combining multiple components that apply pressure to the power device 10, the cooling component 20 and the impedance device 30. By setting the opposite first press-fitting component 41 and second press-fitting component 42 to apply pressure to the power device 10, the cooling component 20 and the impedance device 30, the pressing force can be made more uniform and the pressure application is stable and reliable. More specifically, the first press-fitting component 41 and the second press-fitting component 42 are arranged opposite to each other along a preset direction. The structures of the first press-fitting component 41 and the second press-fitting component 42 can be the same or different. The first press-fitting component 41 includes a frame plate 411, a pressure equalizing plate 412 and an insulating block 413. The pressure equalizing plate 412 and the insulating block 413 are connected to the inner side of the frame plate 411, and the uniform plate 412 is located between the insulating block 413 and the frame plate 411. In some embodiments, in order to make the pressure applied by the first press-fitting component 41 and the second press-fitting component 42 to the device more uniform, some elastic components, such as compression springs, can also be set to adjust the magnitude of the applied pressure. The connecting component 43 may include a plurality of tie rods 431. One end of each tie rod 431 is connected to the first press-fitting component 41, and the other end is connected to the second press-fitting component 42. The tie rods 431 are arranged at intervals in a ring shape. In an embodiment of the present application, the first press-fitting component 41, the second press-fitting component 42, and the connecting component 43 can be combined to form a frame structure, so that the power device 10, the cooling component 20, and the impedance device 30 are located inside the frame structure. This not only makes the relationship between the power device 10, the cooling component 20, and the impedance device 30 closer, but also protects each device. According to some embodiments of the present application, the power device 10 and the impedance device 30 have contact conductive surfaces. The contact conductive surface refers to a surface that can contact a conductive device to achieve electrical connection. Here, the label of the contact conductive surface of the impedance device 30 is 31. The contact conductive surfaces of the power device 10 and the impedance device 30 may include only one, or may include a plurality. And when the contact conductive surfaces of the power device 10 and the impedance device 30 include a plurality, the different contact conductive surfaces may be located on different surfaces of the power device 10 and the impedance device 30. For example, the contact conductive surfaces of the power device 10 and the impedance device 30 include two, and the two contact conductive surfaces are respectively located on the opposite sides of the power device 10 and the impedance device 30. By setting the power device 10 and the impedance device 30 to have contact conductive surfaces, the power device 10 and the impedance device 30 can directly contact and conduct electricity with the conductive device, simplifying the electrical connection relationship between the power device 10 and the impedance device 30 and the conductive device. Compared with the traditional copper busbar or cable connection, a large amount of space and cost can be saved. In an embodiment of the present application, the contact conductive surfaces of the power device 10 and the impedance device 30 are both located on the sides of the power device 10 and the impedance device 30 along a preset direction. In this way, when the contact conductive surface of the power device 10 comes into conductive contact with the impedance device 30 and the cooling component 20, due to the pressing force of the press-fitting structure 40, the reliability of the electrical connection can be further improved. Combined with FIG. 2, further, the impedance device 30 is flat, and the contact conductive surface is located on the flat surface of the impedance device 40. The flat impedance device 30 has a larger flat surface area, making the area of the contact conductive surface larger and improving the stability of the electrical connection between the impedance device 30 and the conductive device. According to some embodiments of the present application, the cooling component 20 is a conductive cooling component, and the conductive contact surfaces of the power device 10 and the impedance device 30 are in contact with the cooling component 20 to achieve electrical connection. The conductive cooling member means that the cooling member 20 has the function of conducting electricity. Specifically, the cooling member 20 may have a metal housing, such as a copper housing or an aluminum housing, etc. By setting the cooling member 20 as a conductive cooling member, and making the conductive contact surfaces of the power device 10 and the impedance device 30 contact the cooling member 20 to achieve electrical connection, the electrical connection relationship between the power device 10 and the impedance device 30 can be simplified. Compared with the traditional copper busbar or cable connection, a large amount of space and cost can be saved. And since the devices in the valve assembly 100 are pressed together by the pressing structure 40, the reliability of the electrical connection is further improved. For example, when the power device 10 includes an IGBT device, the IGBT device has a collector contact conductive surface and an emitter contact conductive surface, and the cooling member 20 can be electrically connected to the collector contact conductive surface and the emitter contact conductive surface. By means of electrical connection, the connection line can be simplified and the reliability of the connection can be improved. In some embodiments, the impedance device 30 may be in a disc shape, and in other embodiments, it may also be in a square flat block shape. In some embodiments, the power device 10 may also be in a disc shape, and the absolute value of the difference between the diameter of the impedance device 30 and the diameter of the power device 10 is not greater than 10% of the diameter of the power device 10. By setting the absolute value of the difference between the diameter of the impedance device 30 and the diameter of the power device 10 to be not greater than 10% of the diameter of the power device 10, the diameter of the impedance device 30 can be made close to the diameter of the power device 10, so that the pressing force between the devices is more uniform during pressing, improving the pressing stability during the pressing process, and further improving the electrical connection reliability between the contact conductive surfaces of the impedance device 30 and the power device 10 and the cooling member 20. In other embodiments, the power devices 10 may also be directly electrically connected to each other through the contact conductive surfaces. For example, when one power device 10 is an IGBT and the other power device 10 is a unidirectional conduction tube, the contact conductive surface of the IGBT is in direct contact with the contact conductive surface of the unidirectional conduction tube to achieve electrical connection. Similarly, the power device 10 and the impedance device 30 may also be directly electrically connected to each other through the contact conductive surfaces. According to some embodiments of the present application, the valve assembly 100 further includes at least one positioning member, and at least one positioning member is disposed between the impedance device 30 and the cooling member 20. The positioning member refers to a component that can position an object to clarify its location. By setting the positioning member, the stability of the positional relationship between the impedance device 30 and the cooling member 20 can be improved, thereby improving the reliability of pressing and the electrical connection reliability between the impedance device 30 and the cooling member 20. Specifically, the positioning member can position the impedance device 30 relative to the cooling member 20. In some embodiments, the positioning member may be a positioning pin, and corresponding through holes 32 may be formed in the impedance device 30 and the cooling device 20 for the positioning pin to pass through and cooperate with. Similarly, a positioning member may also be provided between the power device 10 and the cooling device 20, or a positioning member may be provided between the power devices 10. In addition, as shown in FIGS. 3 and 4, an embodiment of the present application further provides a power module 200, including the valve assembly 100 in any of the above embodiments. In the power module 200 of the present application, by simultaneously press-fitting the power device 10, the cooling device 20, and the impedance device 30 into the press-fitting space AA of the press-fitting structure 40, the distance between the power device 10 and the impedance device 30 can be shortened, so that the distance for the power device 10 and the impedance device 30 to achieve electrical connection is shorter, reducing electrical losses. And since the impedance device 30 is press-fitted into the press-fitting structure 40, the installation space and wiring space of the impedance device 30 are also saved, making the structure of the power module 200 more compact. According to some embodiments of the present application, when the cooling device 20 is a conductive cooling device, the power module 200 further includes a first laminated busbar 50. The first laminated busbar 50 is disposed on one side of all the cooling devices 20 and is electrically connected to some of the cooling devices 20 to electrically connect the power device 10 and the impedance device 30. The first laminated busbar 50 refers to a composite busbar with a multi-layer structure. Specifically, the laminated busbar may include two-layer, three-layer busbars stacked, etc. In this way, the electrical connection of the power device 10 and the impedance device 30 can be realized through the multi-layer busbars of the first laminated busbar 50. In other words, the electrical connection circuit of the impedance device 30 is simplified by the connection method of the busbar. Therefore, the DC electrical connection relationship of the entire valve assembly 10 becomes simple, and the overall structure of the valve assembly 10 is also more compact. Please refer to FIG. 4. Further, the power module 200 further includes a DC busbar 55. The DC busbar 55 is disposed on the side of the first laminated busbar 50 facing away from all the cooling devices 20 and is electrically connected to the first laminated busbar 50. Specifically, the DC busbar 55 refers to a conductive busbar for flowing DC current. One end of the DC busbar 55 can be connected to the DC main circuit of the energy storage system, and the other end is electrically connected to the first laminated busbar 50. In some embodiments, the DC busbar 55 is a DC flexible copper busbar. By disposing the DC busbar 55 and the first laminated busbar 50 on the same side and electrically connecting them, the loop path can be made the shortest, optimizing the loop path. According to some embodiments of the present application, the power module 200 further includes an AC busbar 60. The AC busbar 60 and the first laminated busbar 50 are disposed on opposite sides of all the cooling devices 20, and the AC busbar 60 is electrically connected to another part of the cooling devices 20. The AC busbar 60 refers to a current-carrying busbar for circulating alternating current. One end of the AC busbar 60 can be connected to the AC busbar of the energy storage system, and the other end is electrically connected to the cooling member 20. In some embodiments, the AC busbar 60 is an AC copper busbar. By arranging the AC busbar 60 on the opposite side of the first stacked busbar 50, on the one hand, the interference between AC and DC is reduced, and on the other hand, the peripheral space of the cooling member 20 is fully utilized, making the structure of the valve assembly 100 more compact. According to some embodiments of the present application, when the impedance device 30 and the power device 10 are respectively disposed between two adjacent cooling members 20, and the cooling member 20 is a conductive cooling member, the power module 200 further includes a first capacitor 65. The first capacitor 65 is connected in series with the cooling member 20 adjacent to the impedance device 30 through the first stacked busbar 50 to form a resistor-capacitor branch. The power device 10 and the cooling member 20 adjacent to the power device 10 form a DC output side, and the resistor-capacitor branch is connected in parallel with the DC output side through the first stacked busbar 50. Generally, there are large equivalent internal resistance and equivalent stray inductance inside the energy storage unit. The equivalent internal resistance and equivalent stray inductance not only come from the connection busbars inside the energy storage unit, but also from the busbars connecting the energy storage unit and the power conversion unit in the entire energy storage valve sub-module topology. After the energy storage unit is connected in the manner shown in FIG. 5, the equivalent resistance, equivalent stray inductance inside the energy storage unit, and the DC support capacitor are equivalent to a parallel RLC network. The modes of the energy storage valve sub-module in the entire high-voltage direct-connected energy storage system include two states: the input state and the cut-off state. When the energy storage valve sub-module switches between the input and cut-off states, the current on the main circuit of the high-voltage direct-connected energy storage system enters the energy storage valve sub-module. This current can be regarded as a step current source excitation for the RLC network. Please refer to FIG. 6. FIG. 6 is a schematic diagram of the parallel RLC network equivalent to the energy storage valve sub-module topology. Among them, L represents the equivalent stray inductance, Rdc represents the equivalent internal resistance, I / P represents the step current source excitation, and the power conversion unit in the energy storage valve sub-module is not shown in FIG. 6. Due to the large equivalent stray inductance, the inductive reactance of the equivalent stray inductance L in the energy storage valve sub-module does not match the capacitive reactance of the DC support capacitor. In this case, once under the step current source excitation I / P, the mismatch between the inductive reactance of the equivalent stray inductance L and the capacitive reactance of the DC support capacitor will cause the entire RLC network to undergo underdamped oscillation, forming an underdamped network, thereby causing underdamped oscillation between the DC support capacitor and the energy storage unit. This underdamped oscillation may pose certain hazards to the energy storage valve sub-module, including but not limited to overcurrent in the energy storage unit, resulting in damage, deterioration, and reduced lifespan of the energy storage unit; and an increase in the capacitor current in the energy storage valve sub-module, for example, it can increase by about 30% or so, which will cause an increase in the weight, volume, and cost of the capacitor; if the energy storage valve sub-module is in an overcurrent state for a long time during operation, it will also cause relatively large current stress on the electrical components in the energy storage valve sub-module, etc. Thus, it affects the working reliability of the energy storage valve sub-module. To address this, it can be solved by at least one of the following methods: increasing the capacitance value of the capacitor in the energy storage valve sub-module, reducing the stray inductance, and increasing the resistance. However, considering that the main source of the equivalent stray inductance in the energy storage unit is the connection busbar inside the energy storage unit and the busbar connecting the energy storage unit and the power conversion unit, it is difficult to reduce. And the equivalent internal resistance in the energy storage unit mainly comes from the internal resistance of a large number of series and parallel battery cells. The resistance value of this equivalent internal resistance is relatively low, causing the equivalent internal resistance to fluctuate greatly with the charge and discharge frequency. Therefore, this equivalent internal resistance is not sufficient to suppress the underdamped oscillation either; if a resistor is added to the main circuit of the high-voltage direct-connected energy storage system, since the charge and discharge current of the energy storage in the high-voltage direct-connected energy storage system is as high as thousands of amperes, even adding a resistor of milliohm level will cause huge losses, resulting in a significant temperature rise, which will affect the heat dissipation design and lifespan of the energy storage unit; if the oscillation is suppressed by increasing the capacitance of the capacitor in the energy storage valve sub-module, the capacitance value of the capacitor needs to be increased to several hundred mF, and the increase in the capacitance value of the capacitor is accompanied by a corresponding increase in the volume, weight, and cost of the capacitor, resulting in a certain impact on the applicability and convenience of the energy storage valve sub-module. Taking the above considerations into account, the topology of the energy storage valve sub-module can be improved. Please refer to Figure 7. This application provides a topology schematic diagram of an energy storage valve sub-module. An impedance device 30 for underdamped oscillation is added in the energy storage valve sub-module. The cooling part 20 adjacent to the impedance device 30 is connected in series with the first capacitor 65 through the first laminated busbar 50 to form a resistor-capacitor branch, and this resistor-capacitor branch is connected in parallel with the power device 10 and the cooling part 20 connected to the power device 10 through the first laminated busbar 50 to form a DC output side. Since the impedance device 30 can adjust the resistance value of the impedance in the energy storage valve sub-module to suppress the underdamped oscillation current generated at the moment of switching the switching state of the energy storage valve sub-module, the underdamped oscillation current generated at the moment of switching the switching state of the energy storage valve sub-module is greatly reduced, achieving the effect of suppressing the underdamped oscillation current, and greatly reducing the hazards brought by the underdamped oscillation current to the energy storage valve sub-module, thereby improving the reliability of the energy storage valve sub-module. In addition, in the embodiment of the present application, while the first laminated busbar 50 is electrically connected to the cooling member 20 adjacent to the impedance device 30 and the first capacitor 65, it is also electrically connected to the resistor-capacitor branch and the DC output side. Therefore, the connection lines between the impedance device 30, the first capacitor 65, and the power device 10 can be made simpler through the first laminated busbar 50, reducing the loop resistance and loop stray inductance. Please refer to FIG. 3. Specifically, the first capacitor 65 is disposed on the first side 101 of the valve assembly 100, and the first laminated busbar 50 is disposed on the second side 102 of the valve assembly 100. Among them, the first side 101 and the second side 102 are adjacent. Due to the relative position of the first laminated busbar 50 with respect to the valve assembly 100 being adjacent to the relative position of the first capacitor 65 with respect to the valve assembly 100, it is convenient to place the first laminated busbar 50 and the electrical connection path between the first capacitor 65 and the impedance device 30 can be made shorter. In some embodiments, the directions of the above-mentioned first side 101 and second side 102 on the valve assembly 100 both intersect with the preset direction. Specifically, the direction of the first side 101 on the valve assembly 100 is the Y direction as shown in FIG. 3, and the direction of the second side 102 on the valve assembly 100 is the X direction as shown in FIG. 3. In addition, since the size of the first capacitor 65 is relatively large, in order to reduce the overall size of the power module 200, in the embodiment of the present application, the large surface side of the first capacitor 65 is disposed face-to-face with the first side 101 of the valve assembly 100. The large surface side of the first capacitor 65 is also one side in the thickness direction of the first capacitor 65. Specifically, the thickness direction of the first capacitor 65 is parallel to the direction of the first side 101 on the valve assembly 100. In some embodiments, the end face 651 of the first capacitor 65 near the second side 102 is flush with the side face of the second side 102 of the first capacitor 65. For example, when the end face 651 of the first capacitor 65 near the second side 102 is flush with the side face of the second side 102 of the first capacitor 65, since the size of the first capacitor 65 is relatively large, a part of the first capacitor 65 will protrude from the opposite side, that is, the third side 103 opposite to the second side 102, and a relatively large accommodating space is formed between the first capacitor 65 and the third side 103 of the valve assembly 100. This accommodating space can accommodate other devices without affecting the overall size of the power module 200. In addition, since the first laminated busbar 50 is also disposed on the second side 102, the flush setting method can also keep the first laminated busbar 50 in a relatively flat layer structure, simplify the structure of the first laminated busbar 50, and make the electrical connection line between the first capacitor 65 and the impedance device 30 shorter. Referring to FIG. 8 and in combination with FIG. 9, according to some embodiments of the present application, the power module 200 further includes a second capacitor 70. The capacitance value of the second capacitor 70 is less than that of the first capacitor 65. The second capacitor 70 is connected in parallel with the DC output side through the first laminated busbar 50 and is also connected in parallel with the resistor-capacitor branch. By setting the capacitance value of the second capacitor 70 to be less than that of the first capacitor 65, a certain distinction is also made between the high-frequency current passing through the second capacitor 70 and the high-frequency current passing through the first capacitor 65 at the moment when the energy storage valve sub-module is put into operation. For example, the second capacitor 70 mainly conducts the high-frequency components in the current, and the first capacitor 65 mainly conducts the low-frequency components in the current. In practical applications, when determining the capacitance value of the second capacitor 70, the determination process can be realized through circuit simulation. During the simulation, not only the overvoltage capability at the moment of IGBT turn-off needs to be considered, but also whether the excessive capacitance value of the second capacitor 70 will exacerbate the underdamped oscillation degree of the energy storage valve sub-module. Therefore, the capacitance value of the second capacitor 70 needs to be set within a range that does not cause underdamped oscillation with other devices in the energy storage valve sub-module. In some embodiments, the capacitance value of the second capacitor 70 can be in the order of sub-millifarad (mF). For example, the capacitance value range of the second capacitor 70 includes 10 microfarads (uF) to 300 microfarads (uF). This capacitance value range can be the value range in the high-voltage direct connection scenario. When the second capacitor 70 takes values within this range, it can reduce the overvoltage stress at the moment of IGBT turn-off while reducing the additional impact on the overall topology of the energy storage valve sub-module. In the embodiments of the present application, by integrally connecting a second capacitor 70 in parallel beside the resistor-capacitor branch, the overvoltage stress at the moment of IGBT turn-off can be reduced, the risk of IGBT failure due to excessive overvoltage stress can be reduced, thereby increasing the working reliability of the IGBT and further increasing the working reliability of the energy storage valve sub-module. In addition, in the embodiments of the present application, the second capacitor 70 is connected in parallel with the DC output side through the first laminated busbar 50, which simplifies the connection line between the second capacitor 70, the power device 10 and the resistor-capacitor branch. Referring to FIG. 3, in other embodiments, the power module 200 further includes a second laminated busbar 75. The second capacitor 70 is connected in parallel with the DC output side through the second laminated busbar 75 and is connected in parallel with the resistor-capacitor branch through the first laminated busbar 50. Setting the second laminated busbar 75 to electrically connect the DC output side and the second capacitor 70 makes the connection line simpler, reducing the loop resistance and loop stray inductance. Combining FIG. 3 and FIG. 9, according to some embodiments of the present application, the second capacitor 70 is disposed on the second side 102 or the third side 103 of the valve assembly 10. Among them, the third side 103 is disposed opposite to the second side 102 and is adjacent to the first side 101. Specifically, the second side 102 and the third side 103 are oppositely arranged along the X direction as shown in FIG. 9. By arranging the second capacitor 70 on the second side 102 or the third side 103 of the valve assembly 100, the space on the second side 102 or the third side 103 of the valve assembly 100 can be fully utilized, the structural compactness can be improved, and the second capacitor 70 is also arranged closer to the valve assembly 100, simplifying the electrical connection line of its parallel connection with the resistor-capacitor branch. In some embodiments, the second capacitor 70 is arranged on the third side 103 and is located in the accommodation space formed between the first capacitor 65 and the third side 103 of the valve assembly 100. In some embodiments, the second capacitor 70 is arranged below the AC busbar 60. To better understand the connection relationship between the first stacked busbar 50, the second stacked busbar 75 and the device, the following is described through two specific embodiments. The structures of the valve assemblies 100 in the two specific embodiments are the same. The valve assembly 100 includes two power devices 10, six cooling components 20 and an impedance device 30. The six cooling components 20 are, from top to bottom in sequence, the first cooling component, the second cooling component, the third cooling component, the fourth cooling component, the fifth cooling component and the sixth cooling component. Among them, an impedance device 30 is arranged between the fifth cooling component and the sixth cooling component, and the IGBT and the unidirectional conduction tube of the two power devices 10 are respectively arranged between the other cooling components. In one of the specific embodiments, the second capacitor 70 is arranged on the third side 103 of the valve assembly 100, and the first stacked busbar 50 is arranged on the second side 102 of the valve assembly 100. The first stacked busbar 50 includes three layers of stacked busbars. One layer of the busbar electrically connects the negative terminal of the first capacitor 65 and the sixth cooling component, so that the first capacitor 65 and the sixth cooling component are in series. Another layer of the busbar electrically connects the first cooling component and the fifth cooling component. The last layer of the busbar electrically connects the positive terminal of the first capacitor 65 and the third cooling component. The second stacked busbar 75 includes two layers of stacked busbars. One layer of the busbar electrically connects the negative terminal of the second capacitor 70 and the first cooling component and the fifth cooling component. Another layer of the busbar electrically connects the positive terminal of the second capacitor 70 and the third cooling component. In this way, through the first stacked busbar 50 and the second stacked busbar 75, it is possible to realize that the first capacitor 65 and the impedance device 30 are in series and then in parallel with the second capacitor 70 on the power device 10. In another embodiment, the second capacitor 70 is disposed on the second side 102 of the valve assembly 100, and the first laminated busbar 50 is also located on the second side 102. Thus, the second laminated busbar 75 can be cancelled, and only through the first laminated busbar 50, after the first capacitor 65 and the impedance device 30 are connected in series, they are connected in parallel with the second capacitor 70 on the power device 10. Specifically, the first laminated busbar 50 includes three layers of laminated busbars. One layer of the busbar is electrically connected to the positive terminal of the first capacitor 65, the positive terminal of the second capacitor 70, and the third cooling member. Another layer of the busbar is electrically connected to the first cooling member, the fifth cooling member, and the negative terminal of the second capacitor 70. The last layer of the busbar is electrically connected to the negative terminal of the first capacitor 65 and the sixth cooling member. According to some embodiments of the present application, the impedance device 30 includes a resistor. That is, the suppression circuit in the embodiments of the present application can be implemented by a resistive element. By providing the resistance value required for the resistive element to suppress the underdamped oscillation current generated at the moment when the energy storage valve sub-module is put into operation, it is not only highly economical but also convenient and simple to use, greatly reducing the additional impact on the overall function of the energy storage valve sub-module. Please refer to FIGS. 10 to 13. According to some embodiments of the present application, the power module 200 further includes a bypass switch 78. The bypass switch 78 is disposed on the third side 103 of the valve assembly 100, and one end of the AC busbar 60 is electrically connected to the cooling member 20 through the bypass switch 78. The function of the bypass switch 78 is to disconnect it from the overall circuit when the power device 10 fails, avoiding affecting the operation of the entire energy storage system. Therefore, the operation reliability of the energy storage system is improved. By disposing the bypass switch 78 on the same side as the AC busbar 60, the circuit and structure settings can be simplified. Specifically, the power module 200 further includes an adapter busbar 80. The bypass switch 78 and the cooling member 20 are electrically connected through the adapter busbar 80. In some embodiments, the adapter busbar 80 is disposed on the third side 103 of the valve assembly 100. Further, when the second capacitor 70 is located on the third side 103, the bypass switch 78 and the second capacitor 70 are arranged side by side. Specifically, the direction in which the bypass switch 78 and the second capacitor 70 are arranged side by side is the direction in which the second side 102 and the third side 103 face each other. Specifically, the direction in which the second side 102 and the third side 103 face each other is the X direction as shown in FIG. 6. Of course, in other embodiments, the direction in which the bypass switch 78 and the second capacitor 70 are arranged side by side can also be the direction in which the first side 101 and the fourth side 104 face each other. Specifically, the direction in which the first side 101 and the fourth side 104 face each other is the Y direction as shown in FIG. 9. In this way, the bypass switch 78 and the second capacitor 70 can be centrally arranged, further making the structure of the power module 200 more compact. According to some embodiments of the present application, the power module 200 further includes a controller, which may be a secondary circuit board, or the controller may be disposed on the third side 103 of the valve assembly 100. According to some embodiments of the present application, the power module 200 further includes a power supply 85 connected to the controller. The power supply 85 is disposed on the third side 103 of the valve assembly 100. The second capacitor 70, the bypass switch 78, and the AC busbar 60 form an integral body and are spaced apart from the power supply 85. The fact that the second capacitor 70, the bypass switch 78, and the AC busbar 60 form an integral body and are spaced apart from the power supply 85 means that none of the second capacitor 70, the bypass switch 78, and the AC busbar 60 is inserted into or connected to the power supply 85, and the second capacitor 70, the bypass switch 78, and the AC busbar 60 are all separated from the power supply 85. Since there is sufficient space on the third side 103 of the valve assembly 100 and it is not interfered by the first laminated busbar 50, arranging the relatively large-sized power supply 85 on the third side 103 of the valve assembly 100 can not affect the overall size of the power module 200. In addition, by arranging the second capacitor 70, the bypass switch 78, and the AC busbar 60 to form an integral body and be spaced apart from the power supply 85, the primary AC circuit formed by the second capacitor 70, the bypass switch 78, and the AC busbar 60 can be separated from the secondary control circuit formed by the power supply 85, which not only improves the space utilization rate, but also has good electromagnetic compatibility and takes into account installation and maintenance. In some embodiments, there are multiple power supplies 85, and the multiple power supplies 85 are stacked. According to some embodiments of the present application, the power module 200 further includes an inlet and outlet water pipe 88 communicating with the multiple cooling members 20. The inlet and outlet water pipe 88 is disposed on the fourth side 104 of the valve assembly 100. Although the inlet and outlet water pipe 88 has a small volume, due to its certain extension length, in order to make full use of the surrounding space of the valve assembly 100 and reduce the impact on the size of the power module 200, the inlet and outlet water pipe 88 is disposed on the fourth side 104 of the valve assembly 100. Only the AC busbar 60 protrudes on the fourth side 104, and there is no other device blocking it, so the extension path of the inlet and outlet water pipe 88 is less affected, the structure of the inlet and outlet water pipe 88 is simplified, and the maintenance is facilitated. In addition, the impact on the size of the power module 200 on the fourth side 104 is also small. In some embodiments, the inlet and outlet water pipe 88 extends along the relative direction of the second side 102 and the third side 103. According to some embodiments of the present application, the power module 200 further includes an explosion-proof insulating member 90. The explosion-proof insulating member 90 is disposed on the second side 102 of the valve assembly 100 and is located between the valve assembly 100 and the first laminated busbar 50. In this way, the explosion-proof insulating member 90 can be closely attached to the valve assembly 100, protecting the cooling member 20 from the impact damage caused by the abnormal explosion of the power device 10. According to some embodiments of the present application, the power module 200 further includes a diversion box 95, which is disposed on the fifth side 105 of the valve assembly 100. The fifth side 105 is adjacent to the first side 101, the second side 102, the third side 103, and the fourth side 104, and the inlet and outlet water pipes 88 are located above the diversion box 95 in the vertical direction. By providing the diversion box 95, when abnormal leakage occurs at the inlet and outlet water pipes 88, the cooling member 20, and the connection between the inlet and outlet water pipes 88 and the cooling member 20, the leaked cooling medium can be collected, reducing the damage to each device caused by the leaked cooling medium. In some embodiments, when the inlet and outlet water pipes 88 extend in the relative direction of the second side 102 and the third side 103, the diversion box 95 also extends in the relative direction of the second side 102 and the third side 103. In this way, the diversion box 95 has the same extension direction as the inlet and outlet water pipes 88, and can comprehensively collect the cooling medium leaked on the extension path of the inlet and outlet water pipes 88. Furthermore, the diversion box 95 is provided with a discharge port, which can be connected to the outside for discharge, or connected to the alarm device. Once the alarm is triggered, it will remind the user to handle the leaked cooling medium, improving the operation reliability of the power module 200. According to some embodiments of the present application, referring to FIGS. 10 to 13, a power module 200 is provided, including a valve assembly 100. The valve assembly 100 includes a front side, a rear side, a left side, a right side, an upper side, and a lower side. The first capacitor 65 is disposed on the right side of the valve assembly 100. The first stacked busbar 50 is disposed on the front side of the valve assembly 100 and is electrically connected to the first capacitor 65 and a part of the cooling member 20. The DC busbar 55 is disposed on the front side and is electrically connected to the first stacked busbar 50. The second capacitor 70 is disposed in the accommodation space formed between the rear side of the valve assembly 100 and the first capacitor 65, and is electrically connected to a part of the cooling member 20 through the second stacked busbar 75. The bypass switch 78 is arranged side by side with the second capacitor 70 in the front and rear directions. The AC busbar 60 is disposed on the rear side of the valve assembly 100, and one end of the AC busbar 60 is electrically connected to the cooling member 20 through the bypass switch 78, and the other end extends out from the left side of the valve assembly 100. A plurality of power supplies 85 are disposed on the rear side of the valve assembly 100 and are arranged in upper and lower layers with the second capacitor 70, the bypass switch 78, and the AC busbar 60. The inlet and outlet water pipes 88 are disposed on the left side of the valve assembly 100 and extend in the front and rear directions. In the power module 200 of the embodiment of the present application, by reasonably arranging other devices on the outer periphery of the valve assembly 100, the power module 200 has a compact structure, improves the space utilization rate, has a high power density, good heat dissipation performance, and improves the operation reliability, manufacturability, and maintainability of the power module 200. Secondly, the embodiment of the present application further provides an energy storage valve sub-module, including the power module 200 in any of the above embodiments. In addition, the embodiment of the present application also provides an energy storage system, including the energy storage valve sub-module in any of the above embodiments. Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be covered by the scope of the claims and the description of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A valve assembly, wherein: The invention comprises a power device, a cooling element, an impedance device and a press-fit structure. The press-fit structure has a press-fit space. The power device, the cooling element and the impedance device are arranged in the press-fit space. The power device and the impedance device are electrically connected.

2. The valve assembly according to claim 1, wherein: The power device, the cooling element and the impedance are arranged along a preset direction, and each of the power device and the impedance is adjacent to at least one of the cooling elements.

3. The valve assembly according to claim 2, wherein: The impedance device and the power device are arranged between the same two adjacent cooling members.

4. The valve assembly according to claim 2, wherein: The impedance device and the power device are respectively arranged between two different adjacent cooling members.

5. The valve assembly according to claim 3 or 4, wherein: The power devices include a plurality of power devices, and the plurality of power devices are arranged alternately with the cooling element along the preset direction.

6. The valve assembly according to claim 5, wherein: The power device includes an IGBT or a unidirectional conduction tube, the valve assembly includes two IGBTs and two unidirectional conduction tubes, and the IGBTs and the unidirectional conduction tubes are alternately arranged along the preset direction.

7. The valve assembly according to any one of claims 1 to 6, wherein: The power device and the impedance device have contacting conductive surfaces.

8. The valve assembly according to any one of claims 7, wherein: The impedance device is flat, and the contact conductive surface is located on the flat surface of the impedance device.

9. The valve assembly according to claim 7 or 8, wherein: The cooling member is a conductive cooling member, and the contact conductive surfaces of the power device and the impedance device are in contact with the cooling member to achieve electrical connection.

10. The valve assembly according to claim 9, wherein: The impedance device and the power device are in a pancake shape, and the absolute value of the difference between the diameter of the impedance device and the diameter of the power device is not greater than 10% of the diameter of the power device.

11. The valve assembly according to claim 9 or 10, wherein: The valve assembly further comprises at least one positioning member, and the at least one positioning member is arranged between the impedance device and the cooling member.

12. A power module, wherein: The invention comprises a valve assembly according to any one of claims 1 to 11.

13. The power module according to claim 12, wherein: The impedance device includes a resistor.

14. The power module according to claim 12 or 13, wherein: When the power device, the cooling element and the impedance are arranged along a preset direction, the impedance device and the power device are respectively arranged between two different adjacent cooling elements, and the power device and the impedance device have contact conductive surfaces, the cooling element is a conductive cooling element, and the contact conductive surfaces of the power device and the impedance device are in contact with the cooling element to achieve electrical connection; The power module also includes a first stacked busbar and a first capacitor. The first stacked busbar is arranged on one side of all the cooling elements and is electrically connected to part of the cooling elements. The first capacitor is connected in series with the cooling element adjacent to the impedance device through the first stacked busbar to form a resistor-capacitor branch. The power device and the cooling element adjacent to the power device form a DC output side, and the resistor-capacitor branch is connected in parallel with the DC output side through the first stacked busbar.

15. The power module according to claim 14, wherein: The power module further includes a second capacitor, wherein the capacity of the second capacitor is smaller than that of the first capacitor; The power module also includes a second laminated busbar, through which the second capacitor is connected in parallel with the DC output side and in parallel with the RC branch through the first laminated busbar; or the second capacitor is connected in parallel with the DC output side and in parallel with the RC branch through the first laminated busbar.

16. A storage valve submodule, wherein: Comprising a power module as claimed in any one of claims 12 to 15.

17. An energy storage system, wherein: Comprising the energy storage valve submodule as claimed in claim 15.

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