Power unit and power electronic equipment thereof
By integrating capacitor components and power modules into independent power units and adopting bus capacitors and DC busbar structures, the problems of assembly complexity and insufficient heat dissipation in traditional power electronic equipment are solved, achieving high power density, easy maintenance and efficient heat dissipation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2026-04-07
AI Technical Summary
In traditional power electronic devices, the dispersed installation of capacitor components and power modules increases the complexity of the equipment, makes assembly difficult, results in poor heat dissipation, and leads to insufficient power density, making it difficult to meet the requirements of high reliability and high power density.
The capacitor assembly and power module are integrated into a single power unit. The structure design adopts bus capacitor, BUS-DC bus, BUSN DC bus and BUS+ DC bus. The electrical connection is optimized through insulation settings and connection terminals to achieve modular design and centralized heat dissipation.
It improves the power density and heat dissipation efficiency of the equipment, simplifies assembly and maintenance costs, enhances the structural compactness and flexibility of the equipment, and adapts to the needs of different application scenarios.
Smart Images
Figure CN224097583U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of power electronic equipment technology, specifically a power unit and its power electronic equipment. Background Technology
[0002] With the rapid development of industrial technology, large-scale power electronic equipment is increasingly widely used in numerous industries such as power, transportation, communications, and industrial automation. These devices not only require high reliability and stability, but also place increasingly higher demands on the power rating and power density of the electrical equipment they use. Against this backdrop, how to improve the power density of power electronic equipment, reduce its size and weight, while ensuring the compact structure and ease of maintenance of its internal power units, has become an important direction for current technological research and development. In traditional power electronic equipment, capacitor components and power modules are usually distributed and installed in different parts of the equipment. This design not only increases the complexity and assembly difficulty of the equipment, but also limits further improvements in power density.
[0003] To meet market demand for high-power-density, miniaturized power electronic devices, capacitor components and power modules are increasingly being integrated into a single power unit design. However, this integrated design also faces a series of challenges in practical applications. For example, how to ensure that the capacitor components and power modules inside the power unit maintain good heat dissipation performance and electrical connection reliability while maintaining high power density; how to design a compact and easy-to-maintain power unit to adapt to the needs of different application scenarios; and how to maintain product quality and performance while reducing costs.
[0004] To address the aforementioned issues, while some existing technologies have attempted to integrate capacitor components and power modules into a single independent power unit, these solutions often suffer from problems such as complex structure, difficult assembly, poor heat dissipation, or insufficient power density. Utility Model Content
[0005] To address the shortcomings of existing technologies, this utility model proposes a power unit and its power electronic equipment, aiming to improve the power density and heat dissipation efficiency of the equipment by optimizing the internal structure and electrical connection method of the power unit, while reducing assembly difficulty and maintenance costs, so as to meet the market demand for high-performance, miniaturized power electronic equipment.
[0006] To achieve the above objectives, this utility model provides the following technical solution: A power unit includes a capacitor mounting cavity, a bus capacitor, a BUS-DC bus, a BUSN DC bus, and a BUS+ DC bus. The bus capacitor is uniformly disposed inside the capacitor mounting cavity. The BUS-DC bus, BUSN DC bus, and BUS+ DC bus are fixedly disposed on one side of the capacitor mounting cavity and electrically connected to the bus capacitor. The BUS-DC bus, BUSN DC bus, and BUS+ DC bus are stacked and insulated from each other. Connection terminals are provided on the BUS-DC bus, BUSN DC bus, and BUS+ DC bus.
[0007] In a preferred embodiment, a fixing strip or fixing plate is fixedly provided on the side of the capacitor mounting cavity near the BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar. The fixing strip is located on the outside of the BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar, and the fixing plate is located on the inside of the BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar. The fixing plate is uniformly provided with circular holes, and the outer edge of the busbar capacitor terminal is tangent to the circular hole and inserted into the circular hole.
[0008] In a preferred embodiment, the connection terminal is an L-shaped connecting claw or L-shaped connecting flange extending from one or both ends of the BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar. Each of the BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar has three L-shaped connecting claws extending from one end. The upper sides of the L-shaped connecting claws are at the same height. Each of the BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar has one L-shaped connecting flange extending from one end. The three L-shaped connecting flanges located at the same end are at different heights and are divided into three sections: upper, middle, and lower.
[0009] In a preferred embodiment, the connection terminal is a straight section extending from one or both ends of the BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar. The straight sections on the BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar have different lengths and are divided into three sections: front, middle, and rear.
[0010] In a preferred embodiment, the connection terminal is a planar interface provided at both ends or in the middle of the BUS-DC bus, BUSN DC bus, and BUS+ DC bus. Each of the BUS-DC bus, BUSN DC bus, and BUS+ DC bus has three planar interfaces at one end, or two sets of planar interfaces are provided in the middle of each of the BUS-DC bus, BUSN DC bus, and BUS+ DC bus, with each set of planar interfaces having three interfaces.
[0011] A power electronic device including the power unit further includes a power module. One side of the power module is provided with a DC connection terminal, and the other side of the power module is provided with an AC connection terminal. The DC connection terminal of the power module is one or more of the following: L-shaped connecting claw type, L-shaped folded edge type, straight section type, or planar interface type. The DC connection terminal of the power module is connected to the connection terminal of the power unit.
[0012] A preferred technical solution is a power electronic device including the power unit, which further includes a body and a power electronic device mounting beam. The power electronic device mounting beam is located in the middle of the inner side of the body, and the power unit and power module are stacked vertically or arranged side by side on the power electronic device mounting beam.
[0013] A preferred technical solution is a power electronic device including the aforementioned power unit, wherein the power unit is fixedly installed on the upper side of the power electronic device mounting beam, the connection terminals of the power unit are located on the upper, lower or side part of the power unit, and the power module is fixedly installed on the upper, lower or side part of the power unit.
[0014] In a preferred embodiment, the n power units can be connected to 3n single-phase power modules or to n three-phase power modules, where n is an integer greater than or equal to 1.
[0015] In a preferred embodiment, the connection terminals are stacked together, either vertically or in a single unit, with the BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar separated by an insulating film.
[0016] This invention provides a power unit. It has the following advantages:
[0017] Compact structure and increased power density: The power unit and power electronic equipment are designed with a compact and simple structure, which effectively reduces the assembly difficulty, while the overall size is small and the power density is high.
[0018] Modular design facilitates maintenance: The bus capacitor is designed as a separate modular power unit, achieving functional decoupling and simplifying installation and maintenance. This design makes the independent power module and independent power unit less expensive and smaller in size compared to traditional power modules (containing the bus capacitor).
[0019] Flexible connectivity and configuration: The power unit can be connected to multiple single-phase or three-phase power modules, providing flexible connectivity and configuration options. Furthermore, various connection terminal types are available, including L-shaped claws, L-shaped folded edges, straight sections, and planar interfaces, meeting the needs of different application scenarios.
[0020] High heat dissipation efficiency: The capacitor assembly is centrally installed, which facilitates the design of air ducts for centralized heat dissipation, thereby improving the heat dissipation efficiency of power electronic equipment.
[0021] Simplified electrical connections: The electrical connection between the power module and the capacitor assembly is simple, reducing the difficulty of production operation and on-site maintenance.
[0022] Lightweight design: The power module adopts a busless capacitor solution, which achieves a lightweight design and improves the portability and application range of the equipment.
[0023] High versatility: The shape and connection terminal positions of the power module are not limited to a specific form and can be flexibly adjusted according to actual needs, which enhances the versatility of the design.
[0024] In summary, this utility model, through innovative power unit and power electronic device design, achieves multiple benefits such as compact structure, high power density, easy maintenance, high heat dissipation efficiency, flexible connection, and lightweight design, providing strong support for technological advancement and application promotion in related fields. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of the exploded structure of Embodiment 1 of this utility model;
[0026] Figure 2 This is a schematic diagram of the planar structure of Embodiment 1 of the present utility model;
[0027] Figure 3 This is a schematic diagram of the exploded structure of Embodiment 2 of this utility model;
[0028] Figure 4 This is a three-dimensional structural diagram of Embodiment 3 of the present utility model;
[0029] Figure 5 This is a schematic diagram of the main structure of Embodiment 3 of this utility model;
[0030] Figure 6 This is a schematic diagram of the left-side structure of Embodiment 3 of this utility model;
[0031] Figure 7 This is a three-dimensional structural diagram of Embodiment 4 of the present utility model;
[0032] Figure 8 This is a schematic diagram of the main structure of Embodiment 4 of this utility model;
[0033] Figure 9 This is a schematic diagram of the left side of Embodiment 4 of this utility model;
[0034] Figure 10 This is a three-dimensional structural diagram of Embodiment 5 of the present utility model;
[0035] Figure 11 This is a schematic diagram of the main structure of Embodiment 5 of this utility model;
[0036] Figure 12 This is a schematic diagram of the left side of Embodiment 5 of the present invention;
[0037] Figure 13 This is a schematic diagram of the main structure of Embodiment Six of this utility model;
[0038] Figure 14 This is a top view of the structure of Embodiment Six of this utility model;
[0039] Figure 15 This is a schematic diagram of the power unit structure in Embodiment Six of this utility model;
[0040] Figure 16 This is a schematic diagram of the main structure of Embodiment 7 of this utility model;
[0041] Figure 17 This is a top view of the structure of Embodiment 7 of this utility model;
[0042] Figure 18 This is a schematic diagram of the power unit structure in Embodiment 7 of this utility model;
[0043] Figure 19 This is a schematic diagram of the structure of embodiment eight of the present utility model;
[0044] Figure 20 This is a schematic diagram of the structure of Embodiment Nine of this utility model;
[0045] Figure 21 This is a schematic diagram of the structure of Embodiment 10 of the present utility model;
[0046] In the diagram: 1-Capacitor mounting cavity, 2-Bus capacitor, 3-BUS-DC busbar, 4-BUSN DC busbar, 5-BUS+ DC busbar, 6-Power module, 7-Fixing pressure strip, 8-Fixing pressure plate, 9-Round hole, 10-L-type connecting claw, 11-L-type connecting flange, 12-Straight section, 13-Planar interface, 14-Power module DC connection terminal, 15-AC connection terminal, 16-Power electronic equipment mounting beam, 17-Body. Detailed Implementation
[0047] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example
[0048] Please see Figure 1 and Figure 2 A power unit includes a capacitor mounting cavity 1, a bus capacitor 2, a BUS-DC bus 3, a BUSN DC bus 4, and a BUS+ DC bus 5. The bus capacitors 2 are evenly arranged inside the capacitor mounting cavity 1. The BUS-DC bus 3, BUSN DC bus 4, and BUS+ DC bus 5 are fixedly arranged on one side of the capacitor mounting cavity 1 and electrically connected to the bus capacitors 2. The BUS-DC bus 3, BUSN DC bus 4, and BUS+ DC bus 5 are stacked and insulated from each other. Connection terminals are provided on the BUS-DC bus 3, BUSN DC bus 4, and BUS+ DC bus 5.
[0049] A fixing strip 7 is fixedly installed on one side of the capacitor mounting cavity 1 near the BUS-DC busbar 3, BUSN DC busbar 4 and BUS+ DC busbar 5. The fixing strip 7 is located on the outside of the BUS-DC busbar 3, BUSN DC busbar 4 and BUS+ DC busbar 5. Example
[0050] Please see Figure 3 A power unit includes a capacitor mounting cavity 1, a bus capacitor 2, a BUS-DC bus 3, a BUSN DC bus 4, and a BUS+ DC bus 5. The bus capacitors 2 are evenly arranged inside the capacitor mounting cavity 1. The BUS-DC bus 3, BUSN DC bus 4, and BUS+ DC bus 5 are fixedly arranged on one side of the capacitor mounting cavity 1 and electrically connected to the bus capacitors 2. The BUS-DC bus 3, BUSN DC bus 4, and BUS+ DC bus 5 are stacked and insulated from each other. Connection terminals are provided on the BUS-DC bus 3, BUSN DC bus 4, and BUS+ DC bus 5.
[0051] A fixing plate 8 is fixedly installed on one side of the capacitor mounting cavity 1 near the BUS-DC busbar 3, BUSN DC busbar 4 and BUS+ DC busbar 5. The fixing plate 8 is located inside the BUS-DC busbar 3, BUSN DC busbar 4 and BUS+ DC busbar 5. The fixing plate 8 is evenly provided with circular holes 9. The outer edge of the terminal of the bus capacitor 2 is tangent to the circular hole 9 and is inserted into the circular hole 9. Example
[0052] Please see Figure 1 , Figure 4 , Figure 5 and Figure 6A power electronic device including the power unit of Embodiment 1, further includes a power module 6. One side of the power module 6 is provided with a power module DC connection terminal 14, and the other side of the power module 6 is provided with an AC connection terminal 15. The lower part of the power module 6 is the AC connection terminal 15, which is connected to other internal components of the power electronic device. The power module DC connection terminal 14 is an L-shaped connection claw type, and the power module DC connection terminal 14 is connected to the power module BUS- DC bus, the power module BUSN DC bus, and the power module BUS+ DC bus, respectively.
[0053] The power unit's connection terminals are L-shaped connecting claws 10 extending from both ends of the BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5. Three L-shaped connecting claws 10 extend from one end of each of the BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5, with all L-shaped connecting claws 10 having the same height on their upper sides. The power module DC connection terminals 14 of the power module BUS-DC busbar, power module BUSN DC busbar, and power module BUS+ DC busbar are respectively connected to the L-shaped connecting claws 10 on the power unit's BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5. Example
[0054] Please see Figure 1 , Figure 7 , Figure 8 and Figure 9 A power electronic device including the power unit of Embodiment 1, further includes a power module 6. One side of the power module 6 is provided with a power module DC connection terminal 14, and the other side of the power module 6 is provided with an AC connection terminal 15. The power module DC connection terminal 14 is L-shaped with folded edges, and the power module DC connection terminal 14 is connected to the power module BUS- DC bus, the power module BUSN DC bus and the power module BUS+ DC bus respectively.
[0055] The power unit's connection terminals are L-shaped connecting flanges 11 extending from both ends of the BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5. Each of the three BUS-DC busbars 3, BUSN DC busbar 4, and BUS+ DC busbar 5 has an L-shaped connecting flange 11 extending from one end. The three L-shaped connecting flanges 11 at the same end are at different heights and are divided into upper, middle, and lower sections. The power module DC connection terminals 14 of the power module BUS-DC busbar, power module BUSN DC busbar, and power module BUS+ DC busbar are connected to the L-shaped connecting flanges 11 on the power unit's BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5, respectively. Example
[0056] Please see Figure 1 , Figure 10 , Figure 11 and Figure 12 A power electronic device including the power unit of Embodiment 1, further includes a power module 6. One side of the power module 6 is provided with a power module DC connection terminal 14, and the other side of the power module 6 is provided with an AC connection terminal 15. The power module DC connection terminal 14 is an L-shaped connection claw type, and the power module DC connection terminal 14 is connected to the power module BUS- DC bus, the power module BUSN DC bus and the power module BUS+ DC bus respectively.
[0057] The connection terminals of the power unit are straight sections 12 extending from one or both ends of the BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5. The lengths of the straight sections 12 on the BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5 are different and are divided into three sections: front, middle, and rear. The power module DC connection terminals 14 of the power module BUS-DC busbar, power module BUSN DC busbar, and power module BUS+ DC busbar are respectively connected to the L-shaped connecting claws 10 on the power unit's BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5. Example
[0058] Please see Figure 1 , Figure 13 , Figure 14 and Figure 15 A power electronic device including the power unit of Embodiment 1, further includes a power module 6. One side of the power module 6 is provided with a power module DC connection terminal 14, and the other side of the power module 6 is provided with an AC connection terminal 15. The power module DC connection terminal 14 is an L-shaped connection claw type, and the power module DC connection terminal 14 is connected to the power module BUS- DC bus, the power module BUSN DC bus and the power module BUS+ DC bus respectively.
[0059] The power unit's connection terminals are planar interfaces 13 located at both ends of the BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5. Each of the BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5 has three planar interfaces 13 located at one end. The power module DC connection terminals 14 of the power module's BUS-DC busbar, BUSN DC busbar, and BUS+ DC busbar are connected to the L-shaped connecting claws 10 on the power unit's BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5, respectively. Example
[0060] Please see Figure 1 , Figure 16 , Figure 17 and Figure 18A power electronic device including the power unit of Embodiment 1, further includes a power module 6. One side of the power module 6 is provided with a power module DC connection terminal 14, and the other side of the power module 6 is provided with an AC connection terminal 15. The power module DC connection terminal 14 is an L-shaped connection claw type, and the power module DC connection terminal 14 is connected to the power module BUS- DC bus, the power module BUSN DC bus and the power module BUS+ DC bus respectively.
[0061] The power unit's connection terminals are planar interfaces 13 located in the middle of BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5. Each of these busbars has two sets of planar interfaces 13, with three interfaces in each set. The power module DC connection terminals 14 of the power module BUS-DC busbar, power module BUSN DC busbar, and power module BUS+ DC busbar are connected to the L-shaped connecting claws 10 on the power unit's BUS-DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5, respectively. Example
[0062] Please see Figure 19 A power electronic device including a power unit, further including a power module 6, wherein a power module DC connection terminal 14 is provided on one side of the power module 6 and an AC connection terminal 15 is provided on the other side of the power module 6, wherein the power module DC connection terminal 14 is one or more of the following: L-shaped connection claw type, L-shaped folded edge type, straight section type or planar interface type.
[0063] It also includes a body 17 and a power electronic equipment mounting beam 16. The power electronic equipment mounting beam 16 is located in the middle of the inner side of the body 17. The power units and power modules 6 are stacked vertically or arranged side by side on the power electronic equipment mounting beam 16.
[0064] The power unit is fixedly installed on the upper side of the power electronic equipment mounting beam 16, the connection terminal of the power unit is located on the upper part of the power unit, and the power module 6 is fixedly installed on the upper part of the power unit. Example
[0065] Please see Figure 20 A power electronic device including a power unit, further including a power module 6, wherein a power module DC connection terminal 14 is provided on one side of the power module 6 and an AC connection terminal 15 is provided on the other side of the power module 6, wherein the power module DC connection terminal 14 is one or more of the following: L-shaped connection claw type, L-shaped folded edge type, straight section type or planar interface type.
[0066] It also includes a body 17 and a power electronic equipment mounting beam 16. The power electronic equipment mounting beam 16 is located in the middle of the inner side of the body 17. The power units and power modules 6 are stacked vertically or arranged side by side on the power electronic equipment mounting beam 16.
[0067] The power unit is fixedly installed on the upper side of the power electronic equipment mounting beam 16, the connection terminal of the power unit is located at the lower part of the power unit, and the power module 6 is fixedly installed at the lower part of the power unit. Example
[0068] Please see Figure 21 A power electronic device including a power unit, further including a power module 6, wherein a power module DC connection terminal 14 is provided on one side of the power module 6 and an AC connection terminal 15 is provided on the other side of the power module 6, wherein the power module DC connection terminal 14 is one or more of the following: L-shaped connection claw type, L-shaped folded edge type, straight section type or planar interface type.
[0069] It also includes a body 17 and a power electronic equipment mounting beam 16. The power electronic equipment mounting beam 16 is located in the middle of the inner side of the body 17. The power units and power modules 6 are stacked vertically or arranged side by side on the power electronic equipment mounting beam 16.
[0070] The power unit is fixedly installed on the upper side of the power electronic equipment mounting beam 16, the connection terminal of the power unit is located on the side of the power unit, and the power module 6 is fixedly installed on the side of the power unit.
[0071] In summary, the n power units in this invention can be connected to 3n single-phase power modules 6, or to n three-phase power modules 6, where n is an integer greater than or equal to 1. The connection terminals are stacked together vertically or encapsulated into a single unit, with the BUS- DC busbar 3, BUSN DC busbar 4, and BUS+ DC busbar 5 separated by an insulating film. The power module 6 is not limited to a cuboid shape and can be other irregular shapes. The positions of the DC connection terminals 14 and AC connection terminals 15 of the power module 6 are not limited to the upper and lower parts of the power module 6 and can be other positions. The power module 6 and power units can be two-level or three-level power devices. The order of the DC busbars (Bus+, -, N) inside the power unit from top to bottom is not limited to Bus+ DC busbar 5, BusN DC busbar 4, and Bus- DC busbar 3. The power unit and power module 6 of this utility model have a compact and simple structure, low assembly difficulty, small overall size, and high power density. The power module 6 adopts a busless capacitor-free solution and a lightweight design. The bus capacitor is designed as a separate modular power unit, decoupling its function and facilitating installation and maintenance. The independent power module + independent power unit is lower in cost and smaller in size than the traditional power module (containing a bus capacitor). The capacitor assembly is centrally installed, which facilitates the design of air ducts for centralized heat dissipation and improves the heat dissipation efficiency of power electronic equipment. The electrical connection between the power module and the capacitor assembly is simple, reducing the difficulty of production operation and on-site maintenance.
[0072] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A power unit, characterized in that: The device includes a capacitor mounting cavity (1), a bus capacitor (2), a BUS-DC busbar (3), a BUSN DC busbar (4), and a BUS+ DC busbar (5). The bus capacitor (2) is evenly arranged inside the capacitor mounting cavity (1). The BUS-DC busbar (3), BUSN DC busbar (4), and BUS+ DC busbar (5) are fixedly arranged on one side of the capacitor mounting cavity (1) and electrically connected to the bus capacitor (2). The BUS-DC busbar (3), BUSN DC busbar (4), and BUS+ DC busbar (5) are stacked and insulated from each other. Connection terminals are provided on the BUS-DC busbar (3), BUSN DC busbar (4), and BUS+ DC busbar (5).
2. A power unit according to claim 1, characterized in that: The capacitor mounting cavity (1) is fixedly provided with a fixing strip (7) or a fixing plate (8) on the side near the BUS-DC bus (3), BUSN DC bus (4) and BUS+ DC bus (5). The fixing strip (7) is located outside the BUS-DC bus (3), BUSN DC bus (4) and BUS+ DC bus (5), and the fixing plate (8) is located inside the BUS-DC bus (3), BUSN DC bus (4) and BUS+ DC bus (5). The fixing plate (8) is evenly provided with round holes (9). The outer edge of the terminal of the bus capacitor (2) is tangent to the round hole (9) and inserted into the round hole (9).
3. A power unit according to claim 1, characterized in that: The connection terminal is an L-shaped connecting claw (10) or L-shaped connecting flange (11) extending from one or both ends of the BUS-DC bus (3), BUSN DC bus (4) and BUS+ DC bus (5). Three L-shaped connecting claws (10) extend from one end of the BUS-DC bus (3), BUSN DC bus (4) and BUS+ DC bus (5). The upper height of the L-shaped connecting claws (10) is the same. One L-shaped connecting flange (11) extends from one end of the BUS-DC bus (3), BUSN DC bus (4) and BUS+ DC bus (5). The three L-shaped connecting flanges (11) located at the same end are not at the same height and are divided into three sections: upper, middle and lower.
4. A power unit according to claim 1, characterized in that: The connection terminal is a straight section (12) extending from one or both ends of the BUS-DC busbar (3), BUSN DC busbar (4) and BUS+ DC busbar (5). The straight sections (12) on the BUS-DC busbar (3), BUSN DC busbar (4) and BUS+ DC busbar (5) have different lengths and are divided into three sections: front, middle and rear.
5. A power unit according to claim 1, characterized in that: The connection terminals are planar interfaces (13) provided at both ends or in the middle of the BUS-DC bus (3), BUSN DC bus (4) and BUS+ DC bus (5). Three planar interfaces (13) are provided at one end of the BUS-DC bus (3), BUSN DC bus (4) and BUS+ DC bus (5), or two sets of planar interfaces (13) are provided in the middle of the BUS-DC bus (3), BUSN DC bus (4) and BUS+ DC bus (5), with three planar interfaces (13) in each set.
6. A power electronic device comprising the power unit according to any one of claims 1-5, characterized in that: It also includes a power module (6), one side of which is provided with a power module DC connection terminal (14), and the other side of which is provided with an AC connection terminal (15). The power module DC connection terminal (14) is one or more of the following: L-shaped connection claw type, L-shaped folded edge type, straight section type or planar interface type. The power module DC connection terminal (14) is connected to the connection terminal of the power unit.
7. A power electronic device for a power unit according to claim 6, characterized in that: It also includes a body (17) and a power electronic equipment mounting beam (16), the power electronic equipment mounting beam (16) being located in the middle of the inner side of the body (17), and the power unit and power module (6) being stacked vertically or arranged side by side on the power electronic equipment mounting beam (16).
8. A power electronic device for a power unit according to claim 7, characterized in that: The power unit is fixedly installed on the upper side of the power electronic equipment mounting beam (16), and the connection terminal of the power unit is located on the upper, lower or side of the power unit. The power module (6) is fixedly installed on the upper, lower or side of the power unit.
9. A power electronic device for a power unit according to claim 6, characterized in that: The n power units are connected to 3n single-phase power modules (6) or to n three-phase power modules (6), where n is an integer greater than or equal to 1.
10. A power electronic device for a power unit according to claim 6, characterized in that: The connection terminals are BUS-DC busbar (3), BUSN DC busbar (4) and BUS+ DC busbar (5), which are stacked together or encapsulated into a whole stacked busbar group through an insulating film.