Power conversion device, power assembly and electric vehicle

Abstract

The invention provides a power conversion device, a power assembly and an electric vehicle, and relates to the technical field of power electronics. The power conversion device comprises a circuit board, a power module and an integrated magnetic device. The integrated magnetic device and the power module are electrically connected with the circuit board, and the power module and the circuit board are arranged on the same side of the integrated magnetic device. The integrated magnetic device includes a heat dissipation housing and a plurality of magnetic devices. A plurality of containing cavities are formed in the heat dissipation shell and at least comprise the first containing cavity and the second containing cavity. The plurality of devices includes at least a first magnetic device and a second magnetic device. The first magnetic device is located in the first containing cavity, and the second magnetic device is located in the second containing cavity. According to the integrated magnetic device, a plurality of magnetic devices are arranged in a centralized manner, so that integrated heat dissipation of the magnetic devices can be realized, the loss density of the magnetic devices is improved, and the loss of the power conversion device is reduced.

Description

Technical Field

[0001] The present application relates to the field of power electronics technology, and in particular to a power conversion device, a powertrain, and an electric vehicle. Background Art

[0002] In recent years, with the increasing demand for energy conservation and environmental protection, the proportion of new energy vehicles in the market has also increased year by year. The on-board charger (OBC) is an important part of the power system in new energy vehicles, used to charge the power of the charging pile into the power battery of the electric vehicle. OBC mainly has the functions of rectification charging, DC output and vehicle power distribution. OBC includes power factor correction (PFC) module, direct current-direct current converter (DC-DC) module and LLC (inductance capacitance) module. The magnetic devices of these modules cooperate with the power tube to act as voltage ratio and other functions in the OBC.

[0003] As the OBC works for a long time, the magnetic components of the OBC will generate heat. However, due to the scattered distribution of the magnetic components, the heat dissipation efficiency of the magnetic components is low, resulting in a high internal temperature of the OBC, which affects the working efficiency of the magnetic components and other components, and even causes losses to the magnetic components and other components. In addition, the scattered layout of the magnetic components is not conducive to the high density and integration of the OBC. Summary of the invention

[0004] The present application provides a power conversion device, a powertrain and an electric vehicle to realize an integrated layout of magnetic devices within the power conversion device, thereby realizing integrated heat dissipation of the magnetic devices, and further increasing the loss density of the magnetic devices inside the power conversion device to reduce the loss of the power conversion device.

[0005] In a first aspect, the present application provides a power conversion device. The power conversion device includes a circuit board, a power module and an integrated magnetic device, the integrated magnetic device and the power module are electrically connected to the circuit board, respectively, and the power module and the circuit board are arranged on the same side of the integrated magnetic device. Specifically, the integrated magnetic device includes a heat dissipation housing and a plurality of magnetic devices. A retaining wall is arranged in the heat dissipation housing. The retaining wall divides the internal space of the heat dissipation housing into a plurality of receiving chambers. The aforementioned plurality of receiving chambers may include at least a first receiving chamber and a second receiving chamber. The aforementioned plurality of magnetic devices include at least a first magnetic device and a second magnetic device. In the heat dissipation housing, the first magnetic device is placed in the first receiving chamber, and the second magnetic device is placed in the second receiving chamber.

[0006] In the power conversion device of the present application, the integrated magnetic device centrally arranges multiple magnetic devices in a heat dissipation housing, so that the heat of the multiple magnetic devices can be centrally dissipated through the heat dissipation housing. The integrated magnetic device can realize the integrated layout of the magnetic devices on the one hand, and the integrated heat dissipation of the magnetic devices on the other hand, thereby increasing the loss density of the magnetic devices inside the power conversion device to reduce the loss of the power conversion device.

[0007] In one possible implementation, the thermal conductivity of the baffle wall is smaller than the thermal conductivity of the heat dissipation shell, thereby guiding the heat of the magnetic device to be transferred to the heat dissipation shell and reducing the heat transfer between the magnetic devices in two adjacent accommodating cavities. The baffle wall and the heat dissipation shell may be made of different materials. Specifically, the baffle wall may be made of a material with low thermal conductivity, such as plastic parts, to reduce the manufacturing cost. In this technical solution, the baffle wall may be detachably connected to the heat dissipation shell. Alternatively, in another possible implementation, the baffle wall may also be an integrally formed structure with the heat dissipation shell, so that the heat of the magnetic device may also be transferred to the heat dissipation shell through the baffle wall, thereby increasing the heat dissipation area.

[0008] In a possible implementation, at least one heat dissipation protrusion is provided on the inner wall of the plurality of receiving cavities. One of the at least one heat dissipation protrusion corresponds to a recess of the first magnetic device or the second magnetic device, so that the heat conduction path between the recessed area and the inner wall can be shortened, making the heat conduction path between the outer surface of the magnetic device and the inner wall more uniform.

[0009] In a possible implementation, in the above-mentioned multiple receiving cavities, the distance between the surface of the magnetic device in each receiving cavity and the inner wall of each receiving cavity is less than or equal to a set threshold, thereby reducing the heat conduction path between the magnetic device and the heat dissipation housing to reduce the heat dissipation thermal resistance, and at the same time can reduce the amount of potting glue used, thereby reducing costs. In a specific technical solution, the set threshold can be set to 4 mm.

[0010] In a possible implementation, the inner walls of the plurality of receiving cavities are provided with a plurality of heat dissipation teeth, which are distributed in an array. The plurality of heat dissipation teeth can increase the heat dissipation area between the heat dissipation housing and the magnetic device, and further improve the heat dissipation efficiency.

[0011] In a possible implementation, the high heat loss area of ​​the first magnetic device is arranged in a direction away from the second receiving cavity, and the high heat loss area of ​​the second magnetic device is arranged in a direction away from the first receiving cavity. In this way, the low heat loss area of ​​the magnetic device is placed close to the center of the heat dissipation shell, and the high heat loss area of ​​the magnetic device is placed close to the periphery of the heat dissipation shell, realizing a layout of low-temperature cohesion and high-temperature externalization, so that most of the heat of the magnetic device can be directly transferred out through the heat dissipation shell to reduce thermal coupling between the magnetic devices.

[0012] In one possible implementation, the power conversion device may include an on-board charger. Specifically, the first magnetic device includes a DC-DC transformer and a DC-DC inductor, and the second magnetic device includes an LLC transformer and an LLC inductor. This technical solution can realize the integrated layout and integrated heat dissipation of the DC-DC magnetic device and the LLC magnetic device of the on-board charger.

[0013] In one possible implementation, the heat loss of the DC-DC transformer is smaller than the heat loss of the DC-DC inductor, the DC-DC transformer is arranged in a direction close to the second receiving cavity, and the DC-DC inductor is located on the side of the DC-DC transformer away from the second receiving cavity. The heat loss of the LLC transformer is smaller than the heat loss of the LLC inductor, the LLC transformer is placed in a direction close to the first receiving cavity, and the LLC inductor is located on the side of the LLC transformer away from the first receiving cavity. In the first receiving cavity and the second receiving cavity, the magnetic components with smaller heat loss are placed close to the center of the heat dissipation shell, and the magnetic components with higher heat loss are placed close to the periphery of the heat dissipation shell, realizing a layout of low-temperature internal cohesion and high-temperature external placement, so that most of the heat of the magnetic components can be directly transferred out through the heat dissipation shell to reduce thermal coupling between the magnetic components.

[0014] In a possible implementation, the power conversion device further includes a DC-DC converter and a power distribution unit (PDU), and the DC-DC converter and the PDU are respectively located around the integrated magnetic device. The power conversion device in this technical solution can integrate the OBC, the DC-DC converter and the PDU, which is conducive to the integration and lightweight of the powertrain.

[0015] In a possible implementation, the power conversion device further includes a first cooling plate and a second cooling plate that are arranged opposite to each other. The first cooling plate is provided with a first cooling channel, and the second cooling plate is provided with a second cooling channel. The circuit board is located between the first cooling plate and the second cooling plate. The power module is located between the second cooling plate and the circuit board, and the integrated magnetic device is located between the first cooling plate and the circuit board. In this technical solution, the integrated magnetic device can dissipate heat through the first cooling plate, and the power module can dissipate heat through the second cooling plate, thereby transferring the heat in the power conversion device to the outside.

[0016] Of course, the integrated magnetic device can dissipate heat with multiple cooling plates to increase the heat dissipation efficiency. In another possible implementation, the power conversion device also includes a first cooling plate and a second cooling plate arranged opposite to each other. The first cooling plate is provided with a first cooling channel, and the second cooling plate is provided with a second cooling channel. The circuit board is located on the side of the second cooling plate away from the first cooling plate. The power module is located between the circuit board and the second cooling plate, and the integrated magnetic device is located between the first cooling plate and the second cooling plate. Therefore, the integrated magnetic device can be dissipated through the first cooling plate and the second cooling plate.

[0017] In one possible implementation, the first cooling plate may be a part of the outer shell of the power conversion device. Specifically, the power conversion device may further include a cover plate and a plurality of side plates. The cover plate is arranged opposite to the first cooling plate. The aforementioned plurality of side plates are sequentially connected and located between the cover plate and the first cooling plate. The cover plate, the aforementioned plurality of side plates and the first cooling plate enclose the outer shell of the power conversion device, and the circuit board, the power module, the integrated magnetic device and the second cooling plate are located in the outer shell. The second cooling plate is located between the integrated magnetic device and the cover plate, and the heat dissipation housing is fixedly connected to a side surface of the first cooling plate facing the cover plate. In this technical solution, further, the heat dissipation housing can also be detachably connected to the first cooling plate, so that the integrated magnetic device can be disassembled as a whole for maintenance or replacement.

[0018] In a possible implementation, a heat conduction pad is provided between the heat dissipation housing and the first cooling plate, and the heat conduction pad has a thermal conductivity greater than that of the retaining wall. The heat of the heat dissipation housing is transferred to the outer shell through the heat conduction pad, thereby increasing the heat dissipation rate.

[0019] In another possible implementation, the first cooling plate may also be independently arranged relative to the housing of the power conversion device. The power conversion device may also include a bottom shell and a cover plate, and the cover plate covers the bottom shell. The circuit board, the power module, the integrated magnetic device and the second cooling plate are located in the bottom shell. The first cooling plate is fixedly connected to the side of the bottom shell facing away from the cover plate, and the second cooling plate is located between the integrated magnetic device and the cover plate. In this technical solution, further, the heat dissipation housing can also be an integrated structure with the bottom shell, that is, the bottom plate of the heat dissipation housing can be a part of the bottom shell, which can reduce the height size of the power conversion device.

[0020] In a possible implementation, at least one of the plurality of receiving cavities includes a through hole on a side facing the first cooling plate, and the magnetic device in the at least one receiving cavity partially extends out of the through hole. The magnetic device extends out of the heat dissipation housing, which can shorten the heat conduction distance between the magnetic device and the first cooling channel, thereby reducing the heat dissipation thermal resistance, and at the same time, the material consumption of the heat dissipation housing is reduced, which can reduce the cost.

[0021] In the power converter of the present application, the specific number of the above-mentioned multiple magnetic devices is not limited to two, and these magnetic devices can be placed independently in different receiving chambers. In a possible implementation, when the power conversion device is an on-board charger, the above-mentioned multiple receiving chambers may also include a third receiving chamber, and the first receiving chamber and the second receiving chamber are respectively arranged adjacent to the third receiving chamber. The above-mentioned multiple magnetic devices may also include a third magnetic device, and the third receiving chamber is used to accommodate the third magnetic device, and the third magnetic device is a PFC magnetic device.

[0022] In one possible implementation, the openings of the first receiving chamber, the second receiving chamber, and the third receiving chamber are oriented in the same direction, which can facilitate the installation and removal of the magnetic device. In addition, the first receiving chamber, the second receiving chamber, and the third receiving chamber are arranged in a herringbone shape, which can achieve the miniaturization of the heat dissipation housing. In another possible implementation, the openings of at least two of the first receiving chamber, the second receiving chamber, and the third receiving chamber are oriented in different directions. In this technical solution, the heat dissipation housing has different openings, so that the magnetic device can be installed and removed from different directions according to the actual application scenario.

[0023] In a possible implementation, potting glue is filled between the first receiving cavity and the first magnetic device, and between the second receiving cavity and the second magnetic device, respectively, and the thermal conductivity of the potting glue is greater than the thermal conductivity of the retaining wall. The potting glue can not only fix the magnetic device in the heat dissipation housing, but also transfer the heat of the magnetic device to the heat dissipation housing.

[0024] In a second aspect, the present application provides a powertrain. The powertrain includes a motor, a reducer, and a power conversion device of the first aspect. The motor is connected to the power conversion device, and the motor is connected to the reducer. In the powertrain, the power conversion device can provide electrical energy to the motor so that the motor can operate. The input shaft of the reducer is drivingly connected to the output shaft of the motor to transmit the kinetic energy of the motor. The integrated magnetic device of the power conversion device can realize the integrated layout of the magnetic device and the integrated heat dissipation, thereby increasing the loss density of the magnetic device inside the power conversion device to reduce the loss of the power conversion device, thereby improving the working efficiency of the powertrain.

[0025] In a third aspect, the present application provides an electric vehicle. The electric vehicle includes a power battery and the powertrain of the second aspect described above. The power conversion device of the powertrain is used to charge the power battery, and the power battery is used to provide direct current to the powertrain. In the electric vehicle of the present application, the internal loss of the power conversion device is small, which can improve the efficiency of the power conversion device charging the power battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of charging an electric vehicle provided in an embodiment of the present application;

[0027] Figure 2 A schematic diagram of a power system of an electric vehicle provided in an embodiment of the present application;

[0028] Figure 3 A schematic diagram of a power conversion device provided in an embodiment of the present application;

[0029] Figure 4 Another schematic diagram of a power conversion device provided in an embodiment of the present application;

[0030] Figure 5 A schematic diagram of an integrated magnetic device provided in an embodiment of the present application;

[0031] Figure 6 Another schematic diagram of an integrated magnetic device provided in an embodiment of the present application;

[0032] Figure 7 An exploded schematic diagram of an integrated magnetic device provided in an embodiment of the present application;

[0033] Figure 8 A schematic diagram of a heat dissipation housing provided in an embodiment of the present application;

[0034] Fig. 9 A schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in an embodiment of the present application;

[0035] Fig.10 Another exploded schematic diagram of an integrated magnetic device provided in an embodiment of the present application;

[0036] Fig.11 for Figure 8 A schematic cross-sectional view of the middle heat dissipation housing and the third magnetic device along the AA direction;

[0037] Fig.12 for Figure 8 A schematic cross-sectional view of the middle heat dissipation housing and the second magnetic device along the BB direction;

[0038] Fig.13 Another exploded schematic diagram of the heat dissipation housing and the magnetic device provided in an embodiment of the present application;

[0039] Fig.14 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in an embodiment of the present application;

[0040] Fig.15 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in an embodiment of the present application;

[0041] Fig.16 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in an embodiment of the present application;

[0042] Fig.17 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in an embodiment of the present application;

[0043] Fig.18 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in an embodiment of the present application;

[0044] Fig.19 Another schematic diagram of a power conversion device provided in an embodiment of the present application;

[0045] Fig. 20 Another schematic diagram of a power conversion device provided in an embodiment of the present application;

[0046] Fig.21 Another schematic diagram of a heat dissipation housing provided in an embodiment of the present application;

[0047] Fig. 22 Another schematic diagram of a power conversion device provided in an embodiment of the present application.

[0048] Reference numerals:

[0049] 10-Electric Vehicles

[0050] 11-Power battery

[0051] 12-Powertrain

[0052] 20-Power conversion device

[0053] 21- Shell

[0054] 22-Circuit Board

[0055] 23-Power module

[0056] 24-Integrated Magnetic Devices

[0057] 25-DC-DC Converter

[0058] 26-PDU

[0059] 211- bottom shell

[0060] 212-Cover

[0061] 213-First cooling plate

[0062] 214- Second cooling plate

[0063] 215-Thermal pad

[0064] 241-Heat dissipation housing

[0065] 242-First Magnetic Device

[0066] 243-Second magnetic device

[0067] 244-Third Magnetic Device

[0068] 2411-First Receiving Chamber

[0069] 2412-Second Receiving Chamber

[0070] 2413-Third Storage Chamber

[0071] 2414-Retaining Wall

[0072] 2415-Heat dissipation bulge

[0073] 2416-Heat dissipation gear

[0074] 2417-First through hole

[0075] 2418-Second through hole

[0076] 2419-Third through hole

[0077] 2421-DC-DC Transformer

[0078] 2422-DC-DC Inductor

[0079] 2431-LLC Transformer

[0080] 2432-LLC Inductor DETAILED DESCRIPTION

[0081] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings.

[0082] In order to facilitate understanding of the power conversion device, power assembly and electric vehicle provided by the embodiments of the present application, the application scenarios thereof are described below. As electric vehicle technology gradually matures, users have higher and higher requirements for the performance of electric vehicles. Figure 1 A schematic diagram of charging an electric vehicle provided in an embodiment of the present application, Figure 2 Schematic diagram of the power system of an electric vehicle provided in an embodiment of the present application. Figure 1 and Figure 2As shown, the electric vehicle 10 includes a power battery 11 and a powertrain 12. The powertrain 12 may include a power conversion device 20, a motor and a reducer. Further, the power conversion device 20 may include at least one of a motor controller (MCU), an OBC, a DC-DC converter and a PDU. Among them, the motor controller (MCU) can be used to control the motor. The OBC is used to connect to the charging pile and charge the power battery 11. The power battery 11 is used to provide electrical energy to the electric vehicle 10. In the electric vehicle 10, the problem of charging the power battery 11 is a key issue that determines the performance of the electric vehicle 10 and the user experience. At present, the charging methods of the power battery 11 in the electric vehicle 10 mainly include fast charging and slow charging. Among them, fast charging is that the DC charging pile directly charges the power battery 11 with direct current (DC). Slow charging is that the AC charging pile directly connects the alternating current (AC) to the electric vehicle 10, converts the alternating current into direct current through the OBC, and then charges the power battery 11. Specifically, the power conversion device 20 includes a plurality of magnetic components. For example, the OBC includes a PFC circuit, a DC-DC circuit, and an LLC resonant circuit, and each circuit includes at least one magnetic component. After the PFC circuit converts the connected AC power into DC power, the DC-DC circuit and the LLC resonant circuit convert the DC power from the PFC circuit into high-voltage DC power to charge the power battery 11.

[0083] In this application, OBC is used to convert the DC power of the charging pile into AC power, and supply it to the power battery 11 for charging. The power battery 11 can also provide DC power to the OBC, which is converted into AC power by the OBC to supply external AC power equipment, such as charging other vehicles in vehicle emergency rescue scenarios, or charging small electronic devices. Of course, OBC can also output the DC power of the power battery 11 to the DC-DC converter. The DC-DC converter can output low-voltage DC power of 9V to 16V for charging the on-board battery (such as a 12V battery). The PDU can be connected to the power battery 11, OBC, DC-DC converter, MCU and other components respectively to distribute power to these components to ensure the safety of power use of the entire vehicle.

[0084] In the current power conversion device, taking OBC as an example, the PFC circuit, DC-DC circuit and LLC resonant circuit each include at least one magnetic device. For example, the PFC circuit includes a PFC inductor, the DC-DC magnetic device includes a DC-DC inductor and a DC-DC transformer, and the LLC resonant circuit includes an LLC inductor and an LLC transformer. However, these magnetic devices are dispersed in the OBC. When the OBC is in operation for a long time, the magnetic device will gradually generate heat, causing high heat in multiple locations inside the OBC.

[0085] In view of this, the present application provides a power conversion device, a powertrain and an electric vehicle to realize the integrated layout of magnetic devices within the power conversion device, thereby realizing integrated heat dissipation of the magnetic devices, and further increasing the loss density of the magnetic devices inside the power conversion device to reduce the loss of the power conversion device.

[0086] It should be noted that the terms used in the following embodiments are only for the purpose of describing specific embodiments and are not intended to be limiting of the present application. As used in the specification and appended claims of the present application, the singular expressions "a", "an", "said", "above", "the" and "this" are intended to also include expressions such as "one or more", unless there is a clear indication to the contrary in the context.

[0087] References to "one embodiment" or "some embodiments" etc. described in this specification mean that a particular feature, structure or characteristic described in conjunction with the embodiment is included in one or more embodiments of the present application. Thus, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear at different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0088] In this application, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0089] In addition, in this article, directional terms such as "top", "bottom", "upper" and "lower" are defined relative to the orientation of the structure schematically placed in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they can change accordingly according to the change of the orientation of the structure.

[0090] In the electric vehicle 10 of the present application, the power assembly 12 can adopt a stacked structure. For example, the input shaft of the reducer is connected to the output shaft of the motor, and the power conversion device 20 is stacked on top of the motor and the reducer. The MCU is connected to the power battery 11 and can be used to convert the direct current of the power battery 11 into alternating current and output it to the motor. The motor converts electrical energy into kinetic energy and drives the electric vehicle 10 to travel through the reducer.

[0091] Figure 3 A schematic diagram of a power conversion device provided in an embodiment of the present application, Figure 4 Another schematic diagram of a power conversion device provided in an embodiment of the present application. Figure 3 and Figure 4 As shown, the power conversion device 20 includes a housing 21, and a circuit board 22, a power module 23 and an integrated magnetic device 24 placed in the housing 21. The power module 23 and the integrated magnetic device 24 are electrically connected to the circuit board 22 respectively, and the power module 23 and the integrated magnetic device 24 can be electrically connected through the circuit board 22. The power module 23 and the circuit board 22 are arranged on the same side of the integrated magnetic device 24.

[0092] The integrated magnetic device 24 includes a heat dissipation housing 241 and a plurality of magnetic devices, and the heat dissipation housing 241 is used to accommodate the aforementioned plurality of magnetic devices. A retaining wall 2414 is provided in the heat dissipation housing 241, and the retaining wall 2414 divides the internal space of the heat dissipation housing 241 into a plurality of receiving cavities. The aforementioned plurality of receiving cavities may include at least two receiving cavities. The aforementioned plurality of magnetic devices include at least two magnetic devices.

[0093] Figure 5 A schematic diagram of an integrated magnetic device provided in an embodiment of the present application. Figure 5 As shown, in one embodiment, the plurality of receiving chambers include a first receiving chamber 2411 and a second receiving chamber 2412, and the plurality of magnetic components include a first magnetic component 242 and a second magnetic component 243. In the heat dissipation housing 241, the first magnetic component 242 is placed in the first receiving chamber 2411, and the second magnetic component 243 is placed in the second receiving chamber 2412.

[0094] In the above embodiment, the first magnetic device 242 and the second magnetic device 243 are centrally arranged in the heat dissipation housing 241, and the gap between the first magnetic device 242 and the inner wall of the first receiving cavity 2411, and the gap between the second magnetic device 243 and the inner wall of the second receiving cavity 2412 can be filled with potting glue, so as to fix the first magnetic device 242 and the second magnetic device 243 in the heat dissipation housing 241. In addition, the first receiving cavity 2411 and the second receiving cavity 2412 are separated by a retaining wall 2414, which reduces the thermal coupling between the first magnetic device 242 and the second magnetic device 243, and can reduce the amount of potting glue, thereby reducing costs. The integrated magnetic device 24 of the present application can realize the integrated layout of the magnetic device on the one hand, and realize the integrated heat dissipation of the magnetic device on the other hand, thereby improving the magnetic device loss density inside the power conversion device 20 to reduce the loss of the power conversion device 20.

[0095] In the above embodiment, the thermal conductivity of the potting glue is greater than the thermal conductivity of the retaining wall 2414. The potting glue can not only fix the magnetic device in the heat dissipation housing 241, but also transfer the heat of the magnetic device to the heat dissipation housing 241.

[0096] In addition, the retaining wall 2414 and the heat dissipation housing 241 can be made of different materials. Specifically, the thermal conductivity of the retaining wall 2414 can be smaller than the thermal conductivity of the heat dissipation housing 241, so as to guide the heat of the magnetic device to be transferred to the heat dissipation housing 241 and reduce the heat transfer between the magnetic devices in two adjacent receiving cavities. The retaining wall 2414 can be made of a material with a low thermal conductivity, such as a plastic part, to reduce costs.

[0097] In some embodiments, the high heat loss region of the first magnetic device 242 is arranged in a direction away from the second receiving cavity 2412, and the high heat loss region of the second magnetic device 243 is arranged in a direction away from the first receiving cavity 2411. In this way, the low heat loss regions of the first magnetic device 242 and the second magnetic device 243 are placed close to the center of the heat dissipation housing 241, and the high heat loss regions of the first magnetic device 242 and the second magnetic device 243 are placed close to the periphery of the heat dissipation housing 241, so as to realize a layout of low temperature cohesion and high temperature externalization, so that most of the heat of the first magnetic device 242 and the second magnetic device 243 can be directly transferred out through the heat dissipation housing 241, so as to reduce the thermal coupling between the first magnetic device 242 and the second magnetic device 243. For example, in one embodiment, the first magnetic device 242 may include a DC-DC transformer 2421 and a DC-DC inductor 2422, and the second magnetic device 243 may include an LLC transformer 2431 and an LLC inductor 2432. In practical applications, if the heat loss of the inductor can be less than the heat loss of the transformer, the DC-DC inductor 2422 and the LLC inductor 2432 can be placed at the center of the heat dissipation housing 241, and the DC-DC transformer 2421 and the LLC transformer 2431 can be placed at the periphery of the heat dissipation housing 241. If the heat loss of the inductor can be greater than the heat loss of the transformer, the DC-DC inductor 2422 and the LLC inductor 2432 can be placed at the periphery of the heat dissipation housing 241, and the DC-DC transformer 2421 and the LLC transformer 2431 can be placed at the center of the heat dissipation housing 241.

[0098] In an embodiment of the present application, the specific number of multiple magnetic components of the power conversion device 20 is not limited. The heat dissipation shell 241 can set up receiving cavities corresponding to these magnetic components, so that these magnetic components can be placed independently in a single receiving cavity, thereby isolating these magnetic components from each other.

[0099] The specific structure of the power conversion device 20 is described below using OBC as an example. Figure 6 Another schematic diagram of an integrated magnetic device provided in an embodiment of the present application, Figure 7 An exploded schematic diagram of an integrated magnetic device provided in an embodiment of the present application, Figure 8 A schematic diagram of a heat dissipation housing provided in an embodiment of the present application, Fig. 9 A schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in the embodiment of the present application. Figures 6 to 9As shown, the aforementioned multiple receiving chambers may include a first receiving chamber 2411, a second receiving chamber 2412, and a third receiving chamber 2413. Among them, the first receiving chamber 2411, the second receiving chamber 2412, and the third receiving chamber 2413 are arranged adjacent to each other. The aforementioned multiple magnetic devices include a first magnetic device 242, a second magnetic device 243, and a third magnetic device 244. The first magnetic device 242 is accommodated in the first receiving chamber 2411, the second magnetic device 243 is accommodated in the second receiving chamber 2412, and the third magnetic device 244 is accommodated in the third receiving chamber 2413. Specifically, in the OBC, the first magnetic device 242 may include a DC-DC transformer 2421 and a DC-DC inductor 2422, the second magnetic device 243 includes an LLC transformer 2431 and an LLC inductor 2432, and the third magnetic device 244 includes a PFC magnetic device. The multiple magnetic devices of the OBC are placed centrally to achieve an integrated layout and integrated heat dissipation of the magnetic devices.

[0100] It should be noted that the three magnetic devices and three receiving cavities in this embodiment are only for illustrating the structure of the OBC, and the number of magnetic devices and the number of receiving cavities are not limited to only three. When the heat dissipation housing 241 contains magnetic devices of an MCU, a DC-DC converter and / or a PDU, the specific number of receiving cavities is set according to the number of magnetic devices that need to be placed.

[0101] like Figure 7 As shown, the retaining wall 2414 can be an integrally formed structure with the heat dissipation housing 241 , so the heat of the magnetic device can also be transferred to the heat dissipation housing 241 through the retaining wall 2414 , thereby increasing the heat dissipation area. Fig.10 Another exploded schematic diagram of the integrated magnetic device provided in the embodiment of the present application. Fig.10 As shown, the retaining wall 2414 can also be detachably connected to the heat dissipation housing 241 .

[0102] Fig.11 for Figure 8 A schematic cross-sectional view of the heat dissipation housing and the third magnetic device along the AA direction, Fig.12 for Figure 8 A schematic cross-sectional view of the heat dissipation housing and the second magnetic device along the BB direction. Fig.11 and Fig.12 As shown, in some embodiments, the inner wall of at least one of the plurality of receiving cavities is provided with at least one heat dissipation protrusion 2415. One heat dissipation protrusion 2415 of the at least one heat dissipation protrusion 2415 corresponds to a depression of the magnetic device, so that the heat conduction path between the depression area and the inner wall can be shortened, and the heat conduction path between the outer surface of the magnetic device and the inner wall can be made more uniform, thereby reducing the heat conduction path between the magnetic device and the heat dissipation housing 241 to reduce the heat dissipation thermal resistance, and at the same time, the amount of potting glue used can be reduced, thereby reducing the cost.

[0103] In the above-mentioned multiple receiving cavities, the distance between the surface of the magnetic device in each receiving cavity and the inner wall of each receiving cavity is less than or equal to a set threshold, thereby reducing the heat conduction path between the magnetic device and the heat dissipation housing 241 to reduce the heat dissipation thermal resistance, and at the same time can reduce the amount of potting glue used, thereby reducing costs. In a specific embodiment, the set threshold can be set to 4 mm, that is, the distance between the surface of the magnetic device and the inner wall of the corresponding receiving cavity is less than or equal to 4 mm.

[0104] Fig.13 Another exploded schematic diagram of the heat dissipation housing and magnetic device provided in the embodiment of the present application. Fig.13 As shown, in one embodiment, the inner wall of at least one of the plurality of receiving cavities is provided with a plurality of heat dissipation teeth 2416, and the plurality of heat dissipation teeth 2416 are distributed in an array. The plurality of heat dissipation teeth 2416 can increase the heat dissipation area between the heat dissipation housing 241 and the magnetic device, further improving the heat dissipation efficiency. In the present application, the shape of the heat dissipation teeth 2416 is not specifically limited, for example, the shape of the heat dissipation teeth 2416 can be cylindrical, conical or other irregular shapes.

[0105] In the present application, the heat loss of the above three magnetic components is different, and the temperature of each magnetic component is also different when the power conversion device 20 is working. Specifically, in the OBC, the heat loss of the DC-DC transformer 2421 can be smaller than the heat loss of the DC-DC inductor 2422. Fig.14 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in the embodiment of the present application. Fig. 9 and Fig.14 As shown, the DC-DC transformer 2421 is placed adjacent to the second receiving cavity 2412 and adjacent to the third receiving cavity 2413. In the first receiving cavity 2411, the DC-DC transformer 2421 with lower heat loss is placed close to the center of the heat dissipation housing 241, and the DC-DC inductor 2422 with higher heat loss is placed close to the periphery of the heat dissipation housing 241, so that a low-temperature internal cohesion and high-temperature external layout can be achieved, so that most of the heat of the DC-DC inductor 2422 can be directly transferred out through the heat dissipation housing 241 to reduce thermal coupling between magnetic components.

[0106] Similarly, the heat loss of LLC transformer 2431 may be smaller than the heat loss of LLC inductor 2432 . Fig.15 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in an embodiment of the present application, Fig.16 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in the embodiment of the present application. Fig. 9 , Fig.15 and Fig.16As shown, the LLC transformer 2431 is placed adjacent to the first receiving cavity 2411 and adjacent to the third receiving cavity 2413. In the second receiving cavity 2412, the LLC transformer 2431 with smaller heat loss is placed close to the center of the heat dissipation housing 241, and the LLC inductor 2432 with higher heat loss is placed close to the periphery of the heat dissipation housing 241, so that a layout of low-temperature internal cohesion and high-temperature external placement can be achieved, so that most of the heat of the LLC inductor 2432 can be directly transferred out through the heat dissipation housing 241 to reduce thermal coupling between magnetic components.

[0107] The above-mentioned low-temperature internal cohesion and high-temperature external layout can increase the loss density of the magnetic components inside the power conversion device 20 to reduce the loss of the power conversion device 20, thereby improving the efficiency of the power conversion device 20 charging the power battery 11.

[0108] Of course, the temperature of the transformer and inductor can also be changed by adjusting the loss distribution of the magnetic components. Fig.17 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in the embodiment of the present application. Fig.15 , Fig.16 and Fig.17 As shown, the heat loss of the DC-DC inductor 2422 is less than the heat loss of the DC-DC transformer 2421. The DC-DC inductor 2422 is placed adjacent to the second receiving cavity 2412 and adjacent to the third receiving cavity 2413. Fig.17 As shown, the heat loss of the LLC transformer 2431 may be greater than the heat loss of the LLC inductor 2432. The LLC inductor 2432 is placed adjacent to the first receiving cavity 2411 and adjacent to the third receiving cavity 2413.

[0109] like Figure 7 As shown, in one embodiment, the openings of the first receiving cavity 2411, the second receiving cavity 2412 and the third receiving cavity 2413 are oriented in the same direction, which can facilitate the installation and removal of the magnetic device. In addition, the first receiving cavity 2411, the second receiving cavity 2412 and the third receiving cavity 2413 are arranged in a herringbone shape, which can achieve the miniaturization of the heat dissipation housing 241. At this time, the retaining wall 2414 is in a T-shape.

[0110] In another embodiment, the openings of at least two of the first receiving cavity 2411, the second receiving cavity 2412, and the third receiving cavity 2413 are oriented in different directions. In this embodiment, the heat dissipation housing 241 has different openings, so that the magnetic device can be installed and removed from different directions according to the actual application scenario. Fig.18 Another schematic diagram of the layout of the first magnetic device, the second magnetic device and the third magnetic device provided in the embodiment of the present application. Fig.18As shown, the heat dissipation housing 241 can be opened from two opposite sides. The opening direction of the first receiving cavity 2411 is the same as the opening direction of the third receiving cavity 2413, and the opening direction of the second receiving cavity 2412 is opposite to the opening direction of the first receiving cavity 2411. In this embodiment, the second magnetic device 243 can be located above the first magnetic device 242 and the third magnetic device 244.

[0111] Fig.19 Another schematic diagram of a power conversion device provided in an embodiment of the present application. Fig.19 As shown, the housing 21 of the power conversion device 20 includes a bottom shell 211 and a cover plate 212, and the cover plate 212 covers the bottom shell 211 to form a receiving space, and the circuit board 22, the power module 23 and the integrated magnetic device 24 are located in the receiving space. In addition, the housing 21 also includes a first cooling plate 213 and a second cooling plate 214 arranged opposite to each other, the first cooling plate 213 is provided with a first cooling channel, and the second cooling plate 214 is provided with a second cooling channel. In one embodiment, the circuit board 22 is located between the first cooling plate 213 and the second cooling plate 214. The power module 23 is located between the second cooling plate 214 and the circuit board 22, and the integrated magnetic device 24 is located between the first cooling plate 213 and the circuit board 22. In this embodiment, the integrated magnetic device 24 can dissipate heat through the first cooling plate 213, and the power module 23 can dissipate heat through the second cooling plate 214, so as to transfer the heat in the power conversion device 20 to the outside.

[0112] Of course, the integrated magnetic device 24 can dissipate heat with multiple cooling plates to increase the heat dissipation efficiency. Fig. 20 Another schematic diagram of a power conversion device provided in an embodiment of the present application. Fig. 20 As shown, in another embodiment, the circuit board 22 is located on a side of the second cooling plate 214 away from the first cooling plate 213. The power module 23 is located between the circuit board 22 and the second cooling plate 214, and the integrated magnetic device 24 is located between the first cooling plate 213 and the second cooling plate 214. Therefore, the integrated magnetic device 24 can be dissipated through the first cooling plate 213 and the second cooling plate 214.

[0113] In one embodiment, the first cooling plate 213 may be a part of the housing 21 of the power conversion device 20. Specifically, the bottom shell 211 includes the first cooling plate 213 and a plurality of side plates. The cover plate 212 is arranged opposite to the first cooling plate 213. The aforementioned plurality of side plates are sequentially connected and located between the cover plate 212 and the first cooling plate 213. The cover plate 212, the aforementioned plurality of side plates and the first cooling plate 213 enclose the housing 21 of the power conversion device 20, and the circuit board 22, the power module 23, the integrated magnetic device 24 and the second cooling plate 214 are located in the housing 21. The second cooling plate 214 is located between the integrated magnetic device 24 and the cover plate 212, and the heat dissipation housing 241 is fixedly connected to a side surface of the first cooling plate 213 facing the cover plate 212. In this embodiment, further, the heat dissipation housing 241 can also be detachably connected to the first cooling plate 213, so that the integrated magnetic device 24 can be disassembled as a whole for maintenance or replacement.

[0114] like Fig.19 and Fig. 20 As shown, in one embodiment, a thermal pad 215 is provided between the heat dissipation housing 241 and the first cooling plate 213, and the thermal conductivity of the thermal pad 215 is greater than the thermal conductivity of the retaining wall 2414. The heat of the heat dissipation housing 241 is transferred to the housing 21 through the thermal pad 215, thereby increasing the heat dissipation rate.

[0115] In another embodiment, the first cooling plate 213 may also be independently arranged relative to the housing 21 of the power conversion device 20. The circuit board 22, the power module 23, the integrated magnetic device 24 and the second cooling plate 214 are located in the bottom shell 211. The heat dissipation housing 241 and the bottom shell 211 are an integral structure. The first cooling plate 213 is fixedly connected to the side of the bottom shell 211 away from the cover plate 212, and the second cooling plate 214 is located between the integrated magnetic device 24 and the cover plate 212. In this embodiment, further, the heat dissipation housing 241 can also be an integral structure with the bottom shell 211, that is, the bottom plate of the heat dissipation housing 241 can be a part of the bottom shell 211, so that the height dimension of the power conversion device 20 can be reduced.

[0116] In some embodiments, at least one of the plurality of receiving cavities includes a through hole on a side facing the first cooling plate 213 , and a portion of the magnetic device in the at least one receiving cavity extends out of the through hole. Fig.21 Another schematic diagram of the heat dissipation housing provided in the embodiment of the present application. Fig.21As shown, a first through hole 2417 is provided on a side of the first receiving cavity 2411 facing the first cooling plate 213, and a portion of the first magnetic device 242 extends out of the first through hole 2417. Similarly, a second through hole 2418 is provided on a side of the second receiving cavity 2412 facing the first cooling plate 213, and a portion of the second magnetic device 243 extends out of the second through hole 2418. Similarly, a third through hole 2419 is provided on a side of the third receiving cavity 2413 facing the first cooling plate 213, and a portion of the third magnetic device 244 extends out of the third through hole 2419. The magnetic device extends out of the heat dissipation housing 241, which can shorten the heat conduction distance between the magnetic device and the cooling channel, thereby reducing the heat dissipation thermal resistance, and at the same time, the material consumption of the heat dissipation housing 241 is reduced, which can reduce the cost.

[0117] Fig. 22 Another schematic diagram of a power conversion device provided in an embodiment of the present application. Fig. 22 As shown, the power conversion device 20 further includes a DC-DC converter 25 and a PDU 26 located in the housing 21, and the DC-DC converter 25 and the PDU 26 are respectively located around the integrated magnetic device 24. The power conversion device 20 in this embodiment can integrate the OBC, the DC-DC converter 25 and the PDU 26, which is beneficial to the integration and lightweight of the powertrain 12. Fig. 22 The dotted box in FIG. 1 may be indicated as OBC.

[0118] The above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A power conversion device, characterized in that: The invention comprises a circuit board, a power module and an integrated magnetic device, wherein the integrated magnetic device and the power module are electrically connected to the circuit board respectively, and the power module and the circuit board are arranged on the same side of the integrated magnetic device, wherein: The integrated magnetic device comprises a heat dissipation housing and a plurality of magnetic devices; a retaining wall is arranged inside the heat dissipation housing, and the retaining wall divides the internal space of the heat dissipation housing into a plurality of receiving cavities; the plurality of receiving cavities at least comprises a first receiving cavity and a second receiving cavity arranged adjacently; The plurality of magnetic components include at least a first magnetic component and a second magnetic component; the first magnetic component is placed in the first receiving cavity, and the second magnetic component is placed in the second receiving cavity.

2. The power conversion device according to claim 1, characterized in that: The thermal conductivity of the retaining wall is smaller than the thermal conductivity of the heat dissipation housing.

3. The power conversion device according to claim 1 or 2, characterized in that: At least one heat dissipation protrusion is provided on the inner walls of the plurality of receiving cavities, and one heat dissipation protrusion among the at least one heat dissipation protrusion corresponds to a recess of the first magnetic component or the second magnetic component.

4. The power conversion device according to any one of claims 1 to 3, characterized in that: In the plurality of receiving cavities, a distance between a surface of the magnetic device in each receiving cavity and an inner wall of each receiving cavity is less than or equal to a set threshold.

5. The power conversion device according to any one of claims 1 to 4, characterized in that: The inner walls of the plurality of receiving cavities are provided with a plurality of heat dissipation teeth, and the plurality of heat dissipation teeth are distributed in an array.

6. The power conversion device according to any one of claims 1 to 5, characterized in that: The high heat loss region of the first magnetic device is arranged in a direction away from the second receiving cavity, and the high loss region of the second magnetic device is arranged in a direction away from the first receiving cavity.

7. The power conversion device according to any one of claims 1 to 6, characterized in that: The first magnetic device includes a DC-DC transformer and a DC-DC inductor, and the second magnetic device includes an LLC transformer and an LLC inductor.

8. The power conversion device according to claim 7, characterized in that: The heat loss of the DC-DC transformer is smaller than the heat loss of the DC-DC inductor, the DC-DC transformer is arranged in a direction close to the second receiving cavity, and the DC-DC inductor is located on a side of the DC-DC transformer away from the second receiving cavity; The heat loss of the LLC transformer is smaller than the heat loss of the LLC inductor. The LLC transformer is placed in a direction close to the first receiving cavity, and the LLC inductor is located on a side of the LLC transformer away from the first receiving cavity.

9. The power conversion device according to claim 7 or 8, characterized in that: The power conversion device further includes a DC-DC converter and a power distribution unit, and the DC-DC converter and the power distribution unit are respectively located on the peripheral sides of the integrated magnetic device.

10. The power conversion device according to any one of claims 1 to 9, characterized in that: The power conversion device further comprises a first cooling plate and a second cooling plate arranged opposite to each other; The first cooling plate is provided with a first cooling channel, and the second cooling plate is provided with a second cooling channel; the circuit board is located between the first cooling plate and the second cooling plate; the power module is located between the second cooling plate and the circuit board, and the integrated magnetic device is located between the first cooling plate and the circuit board.

11. The power conversion device according to any one of claims 1 to 9, characterized in that: The power conversion device further comprises a first cooling plate and a second cooling plate arranged opposite to each other; The first cooling plate is provided with a first cooling channel, and the second cooling plate is provided with a second cooling channel; the circuit board is located on the side of the second cooling plate away from the first cooling plate; the power module is located between the circuit board and the second cooling plate, and the integrated magnetic device is located between the first cooling plate and the second cooling plate.

12. The power conversion device according to claim 10 or 11, characterized in that: The power conversion device also includes a cover plate and multiple side plates, the cover plate is arranged opposite to the first cooling plate, and the multiple side plates are connected in sequence and located between the cover plate and the first cooling plate; the cover plate, the multiple side plates and the first cooling plate form a shell of the power conversion device, the circuit board, the power module, the integrated magnetic device and the second cooling plate are located in the shell; the second cooling plate is located between the integrated magnetic device and the cover plate, and the heat dissipation shell is fixedly connected to a side surface of the first cooling plate facing the cover plate.

13. The power conversion device according to claim 12, characterized in that: A thermal pad is provided between the heat dissipation housing and the first cooling plate, and the thermal conductivity of the thermal pad is greater than the thermal conductivity of the retaining wall.

14. The power conversion device according to claim 10 or 11, characterized in that: The power conversion device also includes a bottom shell and a cover plate, the cover plate covers the bottom shell; the circuit board, the power module, the integrated magnetic device and the second cooling plate are located in the bottom shell; the heat dissipation shell and the bottom shell are an integral structure; the first cooling plate is fixedly connected to a side of the bottom shell away from the cover plate, and the second cooling plate is located between the integrated magnetic device and the cover plate.

15. The power conversion device according to any one of claims 10 to 11, characterized in that: At least one of the plurality of receiving cavities comprises a through hole on a side facing the first cooling plate, and a magnetic component portion in the at least one receiving cavity extends out of the through hole.

16. The power conversion device according to any one of claims 7 to 12, characterized in that: The multiple receiving cavities also include a third receiving cavity, and the first receiving cavity and the second receiving cavity are respectively arranged adjacent to the third receiving cavity; the multiple magnetic devices also include a third magnetic device; the third receiving cavity is used to accommodate the third magnetic device, and the third magnetic device is a PFC magnetic device.

17. The power conversion device according to claim 16, characterized in that: The openings of the first receiving cavity, the second receiving cavity and the third receiving cavity are oriented in the same direction, and the first receiving cavity, the second receiving cavity and the third receiving cavity are arranged in a herringbone shape; or At least two of the first receiving cavity, the second receiving cavity and the third receiving cavity have openings in different directions.

18. The power conversion device according to any one of claims 1 to 17, characterized in that: Potting glue is filled between the first receiving cavity and the first magnetic component, and between the second receiving cavity and the second magnetic component, respectively. The thermal conductivity of the potting glue is greater than the thermal conductivity of the retaining wall.

19. A powertrain, characterized in that: The invention comprises a motor, a reducer and a power conversion device as claimed in any one of claims 1 to 14, wherein the motor is connected to the power conversion device, and the motor is connected to the reducer.

20. An electric vehicle, characterized in that: It comprises a power battery and a power assembly as claimed in claim 19, wherein the power conversion device of the power assembly is used to charge the power battery, and the power battery is used to provide direct current to the power assembly.

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