Power assembly and three-level energy storage inverter

Abstract

The utility model provides a kind of power component and three-level energy storage inverter, belong to energy storage inverter technical field, including liquid cooling radiator and IGBT unit, liquid cooling radiator has two cooling surfaces;Two cooling surfaces are symmetrically set relative to first plane;IGBT unit includes two parallel IGBT subunits, two IGBT subunits are one-to-one corresponding and set on two cooling surfaces, and two IGBT subunits are symmetrically set relative to first plane.The utility model's liquid cooling radiator adopts double-sided symmetric cooling structure, doubles heat dissipation area, cooling liquid can simultaneously take away heat from both sides flow channel;Double-sided radiating structure makes single liquid cooling radiator can bear twice the number of IGBT of conventional design, on equivalent volume or smaller volume liquid cooling radiator, more parallel IGBT power components can be integrated, without increasing the size of liquid cooling radiator, reduce cost;Or make existing number of IGBT work at higher power, improve the power density and power level of single power component.

Description

Technical Field

[0001] This utility model belongs to the field of energy storage inverter technology, and more specifically, it relates to a power component and a three-level energy storage inverter. Background Technology

[0002] For three-level energy storage inverters, the current common approach is to use multiplexed parallel IGBTs (Insulated Gate Transistors) to form high-power-density IGBT power modules, thereby increasing the power rating of the energy storage inverter. IGBT cooling typically employs liquid cooling plates, where the IGBTs are mounted on a liquid cooling plate with channels designed and coolant introduced into these channels to dissipate heat from the IGBTs.

[0003] Traditional liquid cooling plates have limited heat dissipation capabilities and cannot effectively remove the large amount of heat generated by high-power-density IGBTs, thus limiting the number of IGBTs that can be integrated into a single module or the maximum output power. To obtain greater power, larger heat sinks or multiple parallel modules are often required, resulting in a large overall size and high cost of power components. Utility Model Content

[0004] The purpose of this invention is to provide a power component and a three-level energy storage inverter, which aims to solve the technical problems of large overall size and high cost of power components due to high power density in the existing technology.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is: to provide a power component, comprising: A liquid-cooled radiator has two cooling surfaces; the two cooling surfaces are symmetrically arranged with respect to a first plane; and The IGBT unit includes two parallel IGBT sub-units, which are attached to the two cooling surfaces in a one-to-one correspondence, and the two IGBT sub-units are symmetrically arranged with respect to the first plane.

[0006] In one possible implementation, the IGBT subunit includes multiple IGBTs, with the multiple IGBTs of two IGBT subunits connected in parallel in a one-to-one correspondence, and arranged symmetrically with respect to the first plane.

[0007] In some embodiments, the plurality of IGBTs in each IGBT subunit are spaced apart along a first direction.

[0008] In some embodiments, the plurality of IGBTs are respectively a first IGBT, a second IGBT, and a third IGBT, wherein the losses of the first IGBT and the second IGBT are equal, and the third IGBT is located between the first IGBT and the second IGBT.

[0009] In some embodiments, each IGBT and its corresponding other IGBT are electrically connected via a first copper busbar; multiple first copper busbars in each IGBT unit are electrically connected via a second copper busbar.

[0010] In some embodiments, the power component is applied to a three-level energy storage inverter, with three groups of IGBT units spaced apart along the first direction, each group of IGBT units constituting a phase IGBT module.

[0011] In one possible implementation, the liquid-cooled radiator has cooling channels, with both ends of the cooling channels extending to the periphery of the IGBT unit.

[0012] In some embodiments, the IGBT subunit includes multiple IGBTs; The cooling channel includes a connected inlet channel and an outlet channel; in the direction of the cooling channel, both the inlet channel and the outlet channel cover multiple IGBTs, the extension paths of the inlet channel and the outlet channel are parallel, and the coolant flows in opposite directions.

[0013] In some embodiments, the cooling channel further includes an intermediate channel connected to the same end of the inlet channel and the outlet channel, and the intermediate channel is located on the periphery of the IGBT unit; One end of the liquid inlet channel is connected to the intermediate channel, and the other end forms a liquid inlet; one end of the liquid outlet channel is connected to the intermediate channel, and the other end forms a liquid outlet; the liquid inlet and the liquid outlet are located on the same side wall of the liquid-cooled radiator.

[0014] The beneficial effects of the power component provided by this utility model are as follows: Compared with the prior art, the power component of this utility model splits the IGBT unit into two symmetrical IGBT sub-units, which are respectively attached to two oppositely arranged cooling surfaces of the liquid cooler, directly doubling the heat dissipation area of ​​the liquid cooler. The liquid cooler efficiently removes the huge heat generated by the two IGBT sub-units from both cooling surfaces. This allows more parallel IGBTs to be integrated on the same or smaller volume liquid cooler without increasing the size of the liquid cooler, thus reducing costs; or it allows the existing number of IGBTs to operate at higher power, improving the power density and power level of a single power component; the symmetrical arrangement of the two parallel IGBT sub-units can increase the current level of the circuit and make the heat generated by the two parallel IGBT sub-units symmetrically applied to the two cooling surfaces of the liquid cooler in space, making the internal temperature field of the cooling plate more uniform.

[0015] This invention also provides a three-level energy storage inverter, including the aforementioned power components.

[0016] The three-level energy storage inverter provided by this utility model, by adopting the above-mentioned power components, can improve the heat dissipation efficiency of the power components, avoid the problem of local hot spots, and can also reduce the size of the power components and reduce costs. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of the power component provided in an embodiment of this utility model; Figure 2 for Figure 1 The right view; Figure 3 A schematic diagram of the internal structure of the liquid-cooled heat sink of the power component provided in an embodiment of the present utility model; Figure 4 for Figure 3 Enlarged structural diagram of point A in the middle circle; Figure 5 A schematic diagram of the power component provided in this embodiment of the present invention, omitting one phase IGBT module; Figure 6 A schematic diagram of the circuit structure of a one-phase IGBT module of the power component provided in this embodiment of the utility model; Figure 7 A schematic diagram of the structure of a one-phase IGBT module of the power component provided in an embodiment of this utility model.

[0019] In the picture: 1. Liquid-cooled radiator; 11. Cooling channel; 111. Liquid inlet channel; 112. Liquid outlet channel; 113. Intermediate channel; 114. Liquid inlet; 115. Liquid outlet; 12. Cooling surface; 13. Radiator body; 131. Heat dissipation base plate; 132. Heat dissipation fins; 133. Baffle plate; 14. Liquid inlet pipe; 15. Liquid outlet pipe; 16. Heat spreader; 2. IGBT unit; 21. First IGBT; 211. Positive terminal; 212. First neutral terminal; 22. Second IGBT; 221. Second neutral terminal; 222. Negative terminal; 23. Third IGBT; 231. First output terminal; 232. Second output terminal; 24. First copper busbar; 25. Second copper busbar; 26. Input copper busbar; 27. Output copper busbar. Detailed Implementation

[0020] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0021] Please refer to the following: Figure 1 and Figure 2 The power component provided by this utility model will now be described. The power component includes a liquid-cooled heat sink 1 and an IGBT unit. The liquid-cooled heat sink 1 has two cooling surfaces 12. The two cooling surfaces 12 are symmetrically arranged with respect to a first plane. The IGBT unit 2 includes two parallel IGBT sub-units. The two IGBT sub-units are attached to the two cooling surfaces 12 in a one-to-one correspondence, and the two IGBT sub-units are symmetrically arranged with respect to the first plane.

[0022] The two cooling surfaces 12 of the liquid cooler 1 can be regarded as the two outer surfaces of the liquid cooler 1. The heat of the IGBT during operation is transferred to the interior of the liquid cooler 1 through the cooling surfaces 12. Coolant flows inside the liquid cooler 1. The coolant flows through the liquid cooler 1 and carries away the heat of each IGBT to dissipate heat from the IGBT.

[0023] The two cooling surfaces 12 are symmetrically arranged with respect to the first plane. It should be noted that the first plane mentioned above is a hypothetical plane and does not actually exist. The first plane is defined here only to clearly show the positional relationship between the two cooling surfaces 12 and the two IGBT sub-units.

[0024] Compared with the prior art, the power component provided by this utility model has a double-sided symmetrical cooling structure in the liquid-cooled heat sink 1, which directly doubles the heat dissipation area. The coolant can efficiently remove heat from both sides of the flow channel at the same time. The double-sided heat dissipation structure allows a single liquid-cooled heat sink 1 to support twice the number of IGBTs in a traditional design. More parallel IGBT power components can be integrated on the liquid-cooled heat sink 1 of the same or smaller volume without increasing the size of the liquid-cooled heat sink 1, thus reducing costs. Alternatively, it can allow the existing number of IGBTs to operate at higher power, thereby improving the power density and power level of a single power component. Furthermore, the two IGBT sub-units are symmetrically arranged, so the heat generated is symmetrically applied to the two cooling surfaces 12 of the liquid cooler 1, making the temperature field inside the cooling plate more uniform. This ensures that the two IGBT sub-units are in an isothermal heat dissipation environment, avoiding the local hot spot problem caused by uneven heat dissipation in traditional parallel modules. This double-sided balanced heat dissipation makes the IGBT chip temperature distribution more uniform, extending device lifespan and improving system reliability.

[0025] In some embodiments, the above-mentioned IGBT subunit may also employ, as Figure 1 The structure shown is described in the following document. Figure 1 An IGBT subunit includes multiple IGBTs. The multiple IGBTs in two IGBT subunits are connected in parallel in a one-to-one correspondence and are arranged symmetrically with respect to the first plane.

[0026] Specifically, each IGBT in one IGBT subunit is connected in parallel with one IGBT in another IGBT subunit, and they are symmetrically arranged along the first plane. This symmetrical power circuit design makes the impedance difference of each parallel branch approach zero, avoiding uneven current distribution caused by impedance differences. Moreover, the corresponding IGBTs in the two IGBT subunits are under exactly the same thermal boundary conditions, which fundamentally eliminates the problem of current imbalance in parallel branches caused by uneven heat dissipation and avoids local overheating failure.

[0027] When the heat generated by an IGBT increases instantaneously, the symmetrical heat dissipation structure can simultaneously improve the cooling efficiency of the IGBTs at its symmetrical positions, forming a thermal balance negative feedback and suppressing heat escape.

[0028] Please see Figure 1 Based on the above implementation method, the multiple IGBTs in each IGBT subunit are distributed at intervals along the first direction.

[0029] Preferably, the liquid-cooled radiator 1 is a cuboid plate structure, with the first direction being the length direction of the liquid-cooled radiator 1. Two cooling surfaces 12 are spaced apart along a second direction, which is the thickness direction of the liquid-cooled radiator 1. The two cooling surfaces 12 can be regarded as the two largest outer surfaces of the liquid-cooled radiator 1.

[0030] Multiple IGBTs are spaced apart along the first direction, which increases the contact area between each IGBT and the cooling surface 12, allowing heat to be transferred more evenly to the cooling surface 12 and effectively reducing the generation of local hot spots. This distribution increases the length of the heat dissipation path, allowing the coolant to more fully absorb the heat generated by the IGBTs in the flow channel, thereby improving the overall heat dissipation efficiency, helping to reduce the junction temperature of the IGBTs, and enhancing their performance and reliability.

[0031] Furthermore, the spacing of multiple IGBTs along the first direction helps to make the electrical connections between the IGBTs more uniform, reducing the unevenness of current distribution. When multiple IGBTs are connected in parallel, if the distribution is too dense, factors such as wiring and parasitic parameters may cause uneven current distribution among the IGBTs. The spacing along the first direction makes the current path more symmetrical and uniform, allowing each IGBT to share the current more evenly, reducing the risk of individual IGBTs being damaged by overcurrent, and improving the stability and reliability of the entire IGBT subunit.

[0032] Furthermore, the spacing of multiple IGBTs along the first direction simplifies the structure of the liquid-cooled heat sink 1, reducing manufacturing difficulty and cost.

[0033] Please see Figure 1 Based on the above implementation, each IGBT and its corresponding IGBT are electrically connected through a first copper busbar 24; the multiple first copper busbars 24 in each IGBT unit 2 are electrically connected through a second copper busbar 25.

[0034] The first copper busbar 24 is used to connect multiple IGBTs in each IGBT subunit, enabling them to be connected in parallel. This allows current to be distributed among the multiple IGBTs, thereby improving the current carrying capacity and power handling capacity of the entire IGBT subunit.

[0035] The second copper busbar 25 is used to connect multiple first copper busbars 24 in each IGBT unit 2, and to collect the current on each first copper busbar 24, thereby realizing the electrical connection between IGBT units 2. This enables the entire power component to transmit and distribute current more efficiently, meeting the demand for high power output.

[0036] In addition, the first copper busbar 24 and the second copper busbar 25 also have good thermal conductivity, which can help dissipate heat from the IGBT to a certain extent. They can conduct the heat generated by the IGBT to the surrounding environment, or transfer the heat to the heat dissipation device through contact with the liquid cooling radiator 1, thereby helping to reduce the temperature of the IGBT and improve its operating stability and reliability.

[0037] In some embodiments, the power components described above are applied to a three-level energy storage inverter, with three groups of IGBT units 2 spaced apart along a first direction, each group of IGBT units 2 constituting a phase IGBT module.

[0038] Three-level inverters typically employ topologies such as neutral point clamping, flying capacitors, or cascaded H-bridges, requiring multiple sets of switching devices to achieve three-phase output. Distributing IGBT units 2 in three groups along the first direction forms a three-phase IGBT module, directly corresponding to the A, B, and C three-phase bridge arm structure of the inverter. For example, in an NPC topology, each phase bridge arm requires multiple IGBTs and diodes, while the three-phase spacing allows for independent layout of the IGBT modules in each phase bridge arm, forming a modular structure. This not only simplifies the topology complexity but also supports flexible expansion. Each phase module can be maintained or replaced independently, improving system maintainability and redundancy.

[0039] In some embodiments, the above-mentioned IGBT subunit may adopt the following... Figure 1 and Figure 5 The structure shown is described in the following document. Figure 1 and Figure 5 The multiple IGBTs are designated as IGBT 21, IGBT 22, and IGBT 23. IGBT 21 and IGBT 22 have equal losses, and IGBT 23 is located between IGBT 21 and IGBT 22.

[0040] Specifically, this power component is applied to a three-level energy storage inverter. For inverter operation, the first IGBT21 and the second IGBT22 have high losses; for rectification operation, the third IGBT23 has high losses; regardless of the operation, the losses of the first IGBT21 and the second IGBT22 are the same.

[0041] Under inverter operation, the first IGBT 21 and the second IGBT 22 undertake the main switching and conduction tasks, with significantly higher losses than the third IGBT 23. Under rectification operation, the third IGBT 23 module becomes the main source of loss, with significantly higher losses than the first IGBT 21 / second IGBT 22. Therefore, the same cooling system needs to handle two distinctly different locations of the highest heat source (the region of the first IGBT 21 / second IGBT 22 during inverter operation and the region of the third IGBT 23 during rectification operation), and the losses of the first IGBT 21 and the second IGBT 22 are the same under all operating conditions, forming a fixed high-temperature zone.

[0042] To solve the above problems, the third IGBT 23 is placed between the first IGBT 21 and the second IGBT 22. Under inverter operation, heat diffuses towards the low-temperature central region, and under rectification operation, heat diffuses towards the low-temperature sides. Regardless of the operating condition, the thermal field is symmetrical, and there is no off-center load problem, ensuring the temperature uniformity of the three IGBTs.

[0043] In the spatial distribution of the cooling surface 12, the first IGBT 21 and the second IGBT 22 are arranged symmetrically with the third IGBT 23 as the center. This ensures that the heat dissipation requirements of the IGBTs on both sides are consistent, avoiding local heat concentration caused by excessive heat generation from one IGBT. The third IGBT 23 is located between the two, and its heat can be evenly transferred to both sides through the cooling surface 12. At the same time, the first IGBT 21 and the second IGBT 22, which have the same heat generation on both sides, will not cause additional heat accumulation in the middle area, reducing the heat dissipation bottleneck in the middle area caused by the high heat generation devices on both sides. The overall heat of the IGBT unit 2 is more evenly distributed on the cooling surface 12, effectively alleviating the problem of local hot spots, improving the service life of the power components, and enhancing operational reliability.

[0044] By reducing hot spots, the temperature of each IGBT is brought closer to the upper limit of its safe operating threshold, avoiding situations where an IGBT is forced to derate due to reaching its temperature limit prematurely. This allows power components to operate stably at higher power levels, indirectly supporting the improvement of the power level of energy storage inverters.

[0045] Please see Figure 6 and Figure 7 Let's take a single-phase IGBT module as an example for explanation. Figure 6 This is a circuit diagram of a single-phase IGBT module. Figure 7 This is a connection diagram of a single-phase IGBT module. The module includes a first IGBT 21, a second IGBT 22, and a third IGBT 23, with the third IGBT 23 located between the first IGBT 21 and the second IGBT 22. The first IGBT 21 and the second IGBT 22 are input IGBTs, and the third IGBT 23 is an output IGBT.

[0046] The upper end of the first IGBT 21 is provided with a positive terminal 211 and a first neutral terminal 212. The upper end of the second IGBT 22 is provided with a second neutral terminal 221 and a negative terminal 222. The positive terminal 211 is connected to the positive plate of the input copper busbar 26, the first neutral terminal 212 and the second neutral terminal 221 are connected to the neutral plate of the input copper busbar 26, and the negative terminal 222 is connected to the negative plate of the input copper busbar 26.

[0047] The lower terminals of the first IGBT 21 and the second IGBT 22 are connected to each other via the first copper busbar 24, and then connected to the lower terminal of the third IGBT 23 via the second copper busbar 25. The upper end of the third IGBT 23 is provided with a first output terminal 231 and a second output terminal 232, both of which are connected to the output copper busbar 27.

[0048] The first IGBT21 includes Figure 6 T1, D1, and Da; the second IGBT22 may include Figure 6The T4, D4, and Db in the third IGBT23 may include... Figure 6 T2, T3, D2, and D3 in the example.

[0049] In some embodiments, the liquid-cooled heat sink 1 described above may also employ, for example... Figure 1 and Figure 5 The structure shown is described in the following document. Figure 1 and Figure 5 A heat exchange plate 16 is provided on the cooling surface 12, and the IGBT sub-unit is fixed on the heat exchange plate 16.

[0050] The heat spreader 16 is used to further eliminate local hot spots. Specifically, the heat spreader 16 has ultra-high planar thermal conductivity, which can instantly diffuse the high heat concentrated on a small area of ​​the IGBT chip core to the entire surface area of ​​the heat spreader 16, preventing the local temperature of a single IGBT chip from becoming too high.

[0051] After the heat from a single IGBT is diffused through the heat spreader 16, the high heat flux density originally concentrated in the IGBT chip core is transformed into a relatively uniform heat load with a lower heat flux density covering the entire area of ​​the heat spreader 16, providing optimized heat exchange conditions for subsequent liquid cooling and improving the heat dissipation efficiency and reliability of the entire liquid cooler 1.

[0052] The heat generated by the first IGBT 21 and the second IGBT 22 can be quickly diffused to the surroundings through the heat spreader 16. The third IGBT 23 is located in the middle, and its heat can be symmetrically diffused to both sides through the heat spreader 16, further reducing the temperature difference between each IGBT. Even if there are slight differences in the local cooling capacity of the liquid cooler 1, the heat spreader 16 can make up for it through efficient heat conduction, further weakening the hot spot from a spatial perspective.

[0053] In some embodiments, the liquid-cooled heat sink 1 described above may also employ, for example... Figure 5 The structure shown is described in the following document. Figure 5 The liquid-cooled radiator 1 has a cooling channel 11 inside; the cooling surface 12 has an opening that covers the IGBT sub-unit; the heat spreader 16 is fixed on the cooling surface 12 and covers the opening, and the heat spreader 16 can directly contact the coolant in the cooling channel 11.

[0054] One side of the heat spreader 16 is in direct contact with the cooling channel 11. On the one hand, the heat conductor between the heat spreader 16 and the cooling channel 11 is omitted; on the other hand, the heat transfer path is shortened, and heat is directly transferred from the heat spreader 16 to the coolant. The path is short and the heat dissipation efficiency is high.

[0055] Specifically, the vapor chamber 16 first diffuses the extremely high local heat flux density of the IGBT, transforming it into a relatively uniform and lower heat flux density on the plate surface that is in direct contact with the coolant. The coolant then directly performs forced convection heat transfer on the diffused plate surface, directly flushing the entire contact surface of the vapor chamber 16 within the flow channels, ensuring that the cooling capacity is evenly applied to the entire plate surface, thereby guaranteeing uniform heat dissipation for each IGBT.

[0056] In some embodiments, the liquid-cooled heat sink 1 described above may also employ, for example... Figure 3 The structure shown is described in the following document. Figure 3 The liquid-cooled radiator 1 has a cooling channel 11, and the two ends of the cooling channel 11 extend to the periphery of the IGBT unit 2.

[0057] Specifically, the cooling channel 11 includes a connected inlet channel 111 and an outlet channel 112; in the direction of the cooling channel 11, both the inlet channel 111 and the outlet channel 112 cover multiple IGBTs, the extension paths of the inlet channel 111 and the outlet channel 112 are parallel, and the coolant flows in opposite directions.

[0058] Coolant flows through the cooling channels 11 of the liquid-cooled radiator 1. Specifically, the liquid-cooled radiator 1 has an inlet 114 communicating with the inlet channel 111 and an outlet 115 communicating with the outlet channel 112. The coolant enters the cavity of the liquid-cooled radiator 1 through the inlet 114, flows through the inlet channel 111 and the outlet channel 112, carries away the heat from each IGBT, and finally flows out from the outlet 115.

[0059] The liquid-cooled radiator 1 has a cavity, within which a cooling channel 11 is formed. The cooling channel 11 can extend in a straight line, in a curved direction, or in a wave-like pattern. The extension path defined here refers to the actual path of the inlet channel 111 and the outlet channel 112.

[0060] In the cooling channel 11, both the inlet channel 111 and the outlet channel 112 cover multiple IGBTs. The coolant passes through each IGBT sequentially in the inlet channel 111, flows back to the outlet channel 112, and then passes through each IGBT sequentially again. The inlet channel 111 and the outlet channel 112 are directly connected to form a single closed loop. The coolant is forced to flow through all preset paths, avoiding local low-speed zones or dead zones caused by uneven flow distribution in traditional multi-branch parallel channels, and ensuring that the coolant velocity and flow rate in the channel corresponding to each IGBT are highly consistent.

[0061] For the inlet channel 111, the coolant flows from the lowest-temperature end to the lowest-temperature end, where the temperature gradually increases due to heat absorption. For the outlet channel 112, the coolant flows from the higher-temperature end (corresponding to the lowest-temperature end of the inlet channel 111) to the outlet 115. Since the inlet channel 111 and the outlet channel 112 have the same extension path but opposite directions, at any point along the first direction, both the lower-temperature portion of the inlet channel 111 and the higher-temperature portion of the outlet channel 112 are simultaneously covered. This structure allows the heat load on the entire cooling surface 12 to be more evenly distributed across the coolant regions with different temperatures.

[0062] The inlet channel 111 receives low-temperature coolant, while the outlet channel 112 ultimately receives high-temperature coolant. The hot and cold channels are adjacent and parallel. The coolant absorbs heat and rises in temperature in the inlet channel 111, but the reverse flow in the outlet channel 112 suppresses the overall temperature rise through heat exchange. The heat dissipated by the high-temperature outlet channel 112 is partially absorbed by the adjacent low-temperature inlet channel 111, thereby reducing the thermal contamination of the outlet channel 112 on the downstream IGBT.

[0063] Compared to traditional unidirectional or non-parallel reverse flow channel designs, the combination of the inlet flow channel 111 and the outlet flow channel 112 in this embodiment balances the differences in heat dissipation capacity at different locations on the cooling surface 12. All IGBTs are in an equivalent cold source environment. Whether located at the front or the end of the inlet flow channel 111, the heat generation per unit flow channel length is approximately equal, significantly reducing the temperature difference between different IGBTs and effectively avoiding the hot spot phenomenon where the temperature of an IGBT at a specific location is much higher than that of other devices.

[0064] By eliminating hot spots, all IGBTs can operate at more similar temperatures, without exceeding safe limits. This means the system's power output is no longer limited by a single overheated IGBT. Under the same cooling conditions, the sustainable output power of the entire power module is increased; or, while outputting the same power, the IGBTs operate at lower and safer temperatures.

[0065] Preferably, the liquid-cooled radiator 1 has a cuboid structure, and its length direction is such that the liquid inlet channel 111 and the liquid outlet channel 112 extend along the first direction.

[0066] In some embodiments, the cooling channel 11 may also employ, for example... Figure 3 The structure shown is described in the following document. Figure 3 The cooling channel 11 also includes an intermediate channel 113, which is connected to the same end of the inlet channel 111 and the outlet channel 112, and is located on the periphery of the IGBT unit 2. The intermediate channel 113 is used to connect the inlet channel 111 and the outlet channel 112, so that the entire cooling channel 11 forms a single closed loop.

[0067] If the inlet channel 111 and the outlet channel 112 are directly connected in the area corresponding to the IGBT unit 2, the high-temperature outlet channel 112 will conduct heat directly to the adjacent inlet channel 111 through the channel wall, resulting in an increase in the inlet temperature; it will also complicate the local channel structure and weaken the mechanical strength of the cooling plate.

[0068] In this embodiment, the intermediate flow channel 113 is located on the periphery of the IGBT unit 2, so that the heat exchange between the liquid inlet flow channel 111 and the liquid outlet flow channel 112 only occurs in the non-heat load area, physically isolating the IGBT heat source from the interface between the hot and cold flow channels, thus blocking the risk of thermal short circuit.

[0069] In addition, after the intermediate flow channel 113 moves the heat exchange between the hot and cold flow channels out of the IGBT area, the liquid inlet flow channel 111 and the liquid outlet flow channel 112 can focus on unidirectional heat absorption and unidirectional heat dissipation within the IGBT unit 2 area. There is only a preset benign heat exchange between the reverse-flowing liquid inlet flow channel 111 and the liquid outlet flow channel 112.

[0070] In some implementations, the aforementioned cooling channel 11 can also adopt, for example... Figure 3 and Figure 4 The structure shown is described in the following document. Figure 3 and Figure 4 One end of the liquid inlet channel 111 is connected to the intermediate channel 113, and the other end forms the liquid inlet 114; one end of the liquid outlet channel 112 is connected to the intermediate channel 113, and the other end forms the liquid outlet 115; the liquid inlet 114 and the liquid outlet 115 are not connected to each other, and the liquid inlet 114 and the liquid outlet 115 are located on the same side wall of the liquid cooler 1.

[0071] The inlet 114 and outlet 115 are not connected and are separated by a baffle 133. The inlet 114 and outlet 115 are located on the same side wall of the liquid cooler 1 to simplify the liquid inlet and outlet structure. Preferably, the inlet 114 and outlet 115 are located on a side wall perpendicular to the first direction.

[0072] The inlet 114 is connected to the inlet pipe 14, and the outlet 115 is connected to the outlet pipe 15. The inlet pipe 14 and the outlet pipe 15 can be made of the same type and model of pipe head, which simplifies installation and reduces costs.

[0073] In some embodiments, the liquid-cooled heat sink 1 described above may also employ, for example... Figure 3 The structure shown is described in the following document. Figure 3 The liquid-cooled radiator 1 has a radiator body 13 inside, which is arranged along the direction of the cooling channel 11. There are gaps between the two ends of the radiator body 13 and the inner cavity sidewall of the liquid-cooled radiator 1. One of the gaps forms an intermediate channel 113. The other gap is provided with a baffle 133, which forms an inlet 114 and an outlet 115.

[0074] The radiator body 13 is used to increase the contact area between the coolant and the solid part inside the liquid-cooled radiator 1. Under the same flow rate and temperature difference, the coolant can remove more heat per unit time, thereby improving the overall heat dissipation efficiency of the liquid-cooled radiator 1.

[0075] The radiator body 13 is arranged along the entire direction of the inlet channel 111 and the outlet channel 112, ensuring that the coolant can continuously and efficiently exchange heat with the radiator body 13 as it flows through the entire effective cooling area. Both the lower temperature inlet channel 111 and the higher temperature outlet channel 112 are supported by the enhanced heat dissipation of the radiator body 13.

[0076] One end of the radiator body 13 is isolated from one side wall of the inner cavity of the liquid-cooled radiator 1, forming an intermediate flow channel 113, which acts as a "U-bend" between the inlet flow channel 111 and the outlet flow channel 112. Coolant flows into this intermediate flow channel 113 from the end of the inlet flow channel 111, and then turns to enter the beginning of the outlet flow channel 112. This space avoids complex bends inside the radiator body 13, simplifies the structure of the radiator body 13, and ensures the continuity of the coolant flow path and low flow resistance.

[0077] The other end of the radiator body 13, the other side wall of the inner cavity of the liquid-cooled radiator 1, and the baffle 133 isolate the inlet 114 and the outlet 115, clearly defining the inlet and outlet areas of the coolant, avoiding short circuits, helping to reduce the local flow resistance of the coolant at the inlet and the back pressure at the outlet, and optimizing the flow characteristics of the entire cooling circuit.

[0078] In some embodiments, the heat sink body 13 may be adopted as follows: Figure 3 and Figure 4 The structure shown is described in the following document. Figure 3 and Figure 4 The heat sink body 13 includes a heat sink substrate 131 and a heat sink tooth 132 group; the heat sink tooth 132 group is disposed on the plate surface of the heat sink substrate 131 parallel to the cooling surface 12; the heat sink tooth 132 group includes a plurality of heat sink teeth 132, which are distributed at intervals along a direction perpendicular to the cooling flow channel 11; each heat sink tooth 132 abuts against the cooling surface 12.

[0079] Among them, some of the heat dissipation teeth 132, heat dissipation substrate 131 and cooling surface 12 form an inlet flow channel 111, and some of the heat dissipation teeth 132, heat dissipation substrate 131 and cooling surface 12 form an outlet flow channel 112.

[0080] Multiple heat dissipation teeth 132 are distributed at intervals perpendicular to the first direction, and in the first direction, the two ends of each heat dissipation tooth 132 are aligned with the two ends of the heat dissipation substrate 131. Each heat dissipation tooth 132 abuts against the cooling surface 12, so the space between each two adjacent heat dissipation teeth 132 can form a flow channel for coolant to flow.

[0081] Specifically, the heat dissipation substrate 131 has a baffle 133 in the middle. One end of the baffle 133 is aligned with one end of the heat dissipation substrate 131, and the other end extends to connect with the cavity sidewall to physically block the liquid inlet 114 and the liquid outlet 115. The baffle 133 divides the heat dissipation teeth 132 into two parts. One part consists of multiple heat dissipation teeth 132, the heat dissipation substrate 131 and the cooling surface 12 forming a liquid inlet channel 111, and the other part consists of multiple heat dissipation teeth 132, the heat dissipation substrate 131 and the cooling surface 12 forming a liquid outlet channel 112.

[0082] The radiator body 13 employs a toothed structure, which disrupts the laminar boundary layer of the coolant and induces turbulence. Under turbulent conditions, the heat exchange between the coolant and the wall of the radiator body 13 is more intense, significantly improving the convective heat transfer coefficient. With the same heat transfer area, the heat dissipation capacity is stronger. Turbulence also helps reduce coolant temperature stratification, resulting in a more uniform temperature distribution across the cross-section of the cooling channel 11.

[0083] Each heat dissipation tooth 132 also abuts against the cooling surface 12, playing a supporting and reinforcing role inside the cooling channel 11, enhancing the mechanical strength and rigidity of the liquid-cooled radiator 1, enabling it to withstand pressure fluctuations in the cooling system, preventing the cooling channel 11 from deforming or collapsing under pressure, and ensuring the stability of the shape of the cooling channel 11 and the flow path of the coolant.

[0084] Based on the same inventive concept, this application also provides a three-level energy storage inverter, including the power components described above.

[0085] The three-level energy storage inverter provided by this utility model, by adopting the above-mentioned power components, can improve the heat dissipation efficiency of the power components, avoid the problem of local hot spots, and can also reduce the size of the power components and reduce costs.

[0086] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A power assembly, characterized by, include: The liquid-cooled radiator (1) has two cooling surfaces (12); The two cooling surfaces (12) are symmetrically arranged with respect to the first plane; and The IGBT unit (2) includes two parallel IGBT sub-units, which are attached to the two cooling surfaces (12) in a one-to-one correspondence, and the two IGBT sub-units are symmetrically arranged with respect to the first plane.

2. The power pack of claim 1, wherein, The IGBT subunit includes multiple IGBTs, and the multiple IGBTs of two IGBT subunits are connected in parallel in a one-to-one correspondence and are arranged symmetrically with respect to the first plane.

3. The power pack of claim 2, wherein, The IGBTs in each IGBT subunit are spaced apart along a first direction.

4. The power pack of claim 3, wherein, The IGBTs are a first IGBT (21), a second IGBT (22), and a third IGBT (23). The first IGBT (21) and the second IGBT (22) have the same loss. The third IGBT (23) is located between the first IGBT (21) and the second IGBT (22).

5. The power pack of claim 3, wherein, Each IGBT and its corresponding other IGBT are electrically connected via a first copper busbar (24); multiple first copper busbars (24) in each IGBT unit (2) are electrically connected via a second copper busbar (25).

6. The power component as claimed in claim 3, characterized in that, The power component is applied to a three-level energy storage inverter, and three groups of IGBT units (2) are distributed at intervals along the first direction. Each group of IGBT units (2) constitutes a phase IGBT module.

7. The power pack of claim 1, wherein, The liquid-cooled radiator (1) has a cooling channel (11), and both ends of the cooling channel (11) extend to the periphery of the IGBT unit (2).

8. The power pack of claim 7, wherein, The IGBT subunit includes multiple IGBTs; The cooling channel (11) includes a connected inlet channel (111) and an outlet channel (112); in the direction of the cooling channel (11), both the inlet channel (111) and the outlet channel (112) cover multiple IGBTs, the extension paths of the inlet channel (111) and the outlet channel (112) are parallel, and the coolant flows in opposite directions.

9. The power pack of claim 8, wherein, The cooling channel (11) further includes an intermediate channel (113), which is connected to the same end of the liquid inlet channel (111) and the liquid outlet channel (112), and the intermediate channel (113) is located on the periphery of the IGBT unit (2); One end of the liquid inlet channel (111) is connected to the intermediate channel (113), and the other end forms a liquid inlet (114); one end of the liquid outlet channel (112) is connected to the intermediate channel (113), and the other end forms a liquid outlet (115); the liquid inlet (114) and the liquid outlet (115) are located on the same side wall of the liquid-cooled radiator (1).

10. A three-level energy storage inverter, characterized by, Includes the power component as described in any one of claims 1-9.

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