Inverter and electric vehicle

Abstract

The utility model provides an inverter. In the inverter, a recessed space is formed in the surface of one side, close to a printed circuit board assembly, of an electromagnetic shielding plate, and a power conversion auxiliary circuit element on the surface of one side, close to the electromagnetic shielding plate, of a printed circuit board is arranged to be inserted into the recessed space of the electromagnetic shielding plate. Therefore, the distance between the printed circuit board assembly and the power device is reduced, the size of the inverter is reduced, and the working performance of the inverter is improved.

Description

Technical Field

[0001] This utility model generally relates to the field of power conversion, and more particularly to inverters and electric vehicles. Background Technology

[0002] Inverters are key components of the e-drive system in electric vehicles, converting the direct current (DC) stored in the vehicle's battery into alternating current (AC) to power the vehicle's motors. This conversion process allows the vehicle's motors to operate efficiently under various speed and load conditions. Furthermore, inverters also manage energy flow during regenerative braking, converting the AC power generated by the vehicle's motors back to DC to charge the vehicle's battery.

[0003] During inverter operation, the power devices within the inverter frequently perform switching operations. These high-frequency switching operations generate significant electromagnetic interference (EMI) noise, which degrades the electrical performance of the power conversion auxiliary circuitry on the printed circuit board assembly (PCBA) placed close to the power devices. For example, it worsens the signal quality generated by the power conversion drive circuitry and power conversion control circuitry on the PCBA. Therefore, an electromagnetic shielding plate is needed between the power devices and the PCBA to reduce the EMI interference from the power devices to the electrical components on the PCBA.

[0004] Figure 1 A schematic diagram of the structure of a conventional inverter 100 is shown.

[0005] like Figure 1 As shown, a conventional inverter 100 includes a housing, a heat sink 110, power devices 120, an electromagnetic shielding plate 130, and a PCBA 140. The heat sink 110, power devices 120, electromagnetic shielding plate 130, and PCBA 140 are arranged sequentially from bottom to top within the housing. A DC-Link capacitor 150 is arranged between the electromagnetic shielding plate 130 and the bottom plate of the housing. Furthermore, a bus assembly connected to the DC-Link capacitor 150, such as an AC bus 151 and a high-voltage DC bus 153, is arranged on the upper surface of the power devices 120. The PCBA 140 can be formed as a multilayer printed circuit board, and electrical components for power conversion auxiliary circuitry are arranged on the upper and lower surfaces of the printed circuit board, respectively. The power conversion auxiliary circuitry may include, for example, a power conversion control circuit and a power conversion drive circuit, such as a gate drive circuit 161 and an ISO PSU circuit 163. In addition, a low-voltage terminal (LV Terminal) 170 for a low-voltage electrical system can be arranged on the PCBA 140, and the LV Terminal 170 extends upward through the upper cover plate 180 of the housing.

[0006] exist Figure 1 In the example, the upper and lower surfaces of the electromagnetic shielding plate 130 are formed as flat surfaces. For electrical safety design considerations, such as clearance and creepage distance between electrical components and electromagnetic interference from power devices to electrical components on the PCBA 140, a specified spacing needs to be maintained between the surface of the electromagnetic shielding plate 130 and the electrical components on the PCBA 140, as well as between the surface of the electromagnetic shielding plate 130 and the electrical components on the power device 120. The spacing in the Z-direction between the electromagnetic shielding plate 130 and the PCBA 140 depends on the maximum component height of the electrical components arranged on the side surface of the PCBA 140 closest to the electromagnetic shielding plate 130. The side surface of the PCBA 140 closest to the electromagnetic shielding plate 130 typically houses electrical components with larger component heights, such as inductors or transformers, resulting in a larger spacing in the Z-direction between the electromagnetic shielding plate 130 and the PCBA 140. This leads to a larger device size in the inverter (e.g., ...). Figure 1 The inverter in the middle has a dimension of 65mm in the Z direction, which is not conducive to the miniaturization of the inverter.

[0007] Furthermore, PCBA 140 contains power conversion control circuitry for controlling the power conversion of power device 120. This necessitates establishing an electrical connection between PCBA 140 and power device 120 for signal transmission. For example, an electrical connection is established between the device pins of power device 120 and the electrical component pins on PCBA 140 for signal transmission. This electrical connection causes signal transmission loss, thereby reducing the signal quality of the transmitted signal. The greater the distance between PCBA 140 and power device 120 in the Z-direction, the longer the electrical connection between them becomes, resulting in greater signal transmission loss. This leads to significant signal transmission loss between PCBA 140 and power device 120, ultimately affecting the inverter's operating performance. Utility Model Content

[0008] This invention provides an inverter. In this inverter, a recessed space is formed on the surface of the electromagnetic shielding plate near the printed circuit board assembly, and the power conversion auxiliary circuit elements on the surface of the printed circuit board near the electromagnetic shielding plate are arranged to be inserted into the recessed space of the electromagnetic shielding plate. This reduces the distance between the printed circuit board assembly and the power devices, thereby reducing the size of the inverter and reducing signal transmission loss between the printed circuit board assembly and the power devices, thus improving the operating performance of the inverter.

[0009] According to one aspect of the present invention, an inverter is provided, comprising: at least one power device for performing unidirectional power conversion from direct current to alternating current or bidirectional power conversion between direct current and alternating current; a printed circuit board assembly including a printed circuit board and power conversion auxiliary circuitry disposed on the printed circuit board; and an electromagnetic shielding plate disposed between the power device and the printed circuit board assembly, wherein a recessed space is formed on a side surface of the electromagnetic shielding plate near the printed circuit board assembly, wherein power conversion auxiliary circuitry elements on the side surface of the printed circuit board near the electromagnetic shielding plate are arranged to be inserted into the recessed space of the electromagnetic shielding plate.

[0010] Optionally, the recessed space may be formed at a position corresponding to a first power conversion auxiliary circuit element in the power conversion auxiliary circuit elements on the surface of the printed circuit board near the electromagnetic shielding plate, the first power conversion auxiliary circuit element including a power conversion auxiliary circuit element with a height greater than a predetermined element height.

[0011] Optionally, the recessed space may include at least two recessed spaces, the recessed depth of each recessed space being determined according to the component height of the corresponding first power conversion auxiliary circuit element, or the recessed depth of each recessed space being determined according to the component height of the corresponding first power conversion auxiliary circuit element, the electromagnetic interference parameters of the power device, and the magnetic permeability of the electromagnetic shielding plate.

[0012] Optionally, the position of the first power conversion auxiliary circuit element on the printed circuit board can be arranged to be offset from the position of the power device.

[0013] Optionally, the first power conversion auxiliary circuit element can be an electromagnetic interference insensitive element, and the element height of the first power conversion auxiliary circuit element exceeds the element height of all electromagnetic interference sensitive elements on the surface of the printed circuit board near the electromagnetic shielding plate.

[0014] Optionally, the electromagnetic shielding plate may be made of a material with a permeability not less than a first permeability.

[0015] Optionally, the first permeability can be determined based on the electromagnetic interference parameters of the power device and the spacing between the printed circuit board assembly and the power device.

[0016] Optionally, the electromagnetic interference parameters may include the switching frequency and switching speed of the power device.

[0017] Optionally, some or all of the recessed spaces can be formed as through recessed spaces.

[0018] Optionally, the surfaces of the power conversion auxiliary circuit elements on the surface of the printed circuit board near the electromagnetic shielding plate may be coated with an electromagnetic interference shielding enhancement material. The surface of the first power conversion auxiliary circuit element on the surface of the printed circuit board near the electromagnetic shielding plate may be coated with an electromagnetic interference shielding enhancement material. The first power conversion auxiliary circuit element includes a power conversion auxiliary circuit element with a height greater than a predetermined element height. Alternatively, the surface of the electromagnetic interference sensitive element on the surface of the printed circuit board near the electromagnetic shielding plate may be coated with an electromagnetic interference shielding enhancement material.

[0019] According to another aspect of the embodiments of this specification, an electric vehicle is provided, including the inverter described above. Attached Figure Description

[0020] A further understanding of the nature and advantages of this specification can be achieved by referring to the following figures. In the figures, similar components or features may have the same reference numerals.

[0021] Figure 1 An example schematic diagram of a conventional inverter is shown.

[0022] Figure 2 A side view of an inverter according to an embodiment of the present invention is shown.

[0023] Figure 3 A top view of an electromagnetic shielding plate according to an embodiment of the present invention is shown.

[0024] Figure 4 It shows Figure 3 The diagram shows a cross-sectional view of the electromagnetic shielding plate.

[0025] Figure 5 A cross-sectional schematic diagram of an electromagnetic shielding plate according to another embodiment of the present invention is shown.

[0026] Figure 6 A cross-sectional schematic diagram of an electromagnetic shielding plate according to another embodiment of the present invention is shown.

[0027] Attached image description

[0028] 100 Inverter 110 Heatsink 120 Power Devices 130 Electromagnetic Shielding Plate

[0029] 140PCBA, 150DC-Link capacitor, 161 gate driver circuit, 163ISO PSU

[0030] 170 Low-voltage terminal block 180 Housing top cover plate

[0031] 200 inverter, 210 heat sink, 220-1 power device, 220-2 power device

[0032] 220-3 Power Devices; 230 Electromagnetic Shielding Boards; 240 PCBAs; 251 Electromagnetic Interference-Insensitive Components

[0033] 253 Electromagnetic Interference Sensing Component; 260 Housing Top Cover; 270 Low-Voltage Terminal Block

[0034] 310 Electromagnetic shielding plate, 320 through hole, 321 groove, 321-1 groove, 321-2 groove, 323 through hole Detailed Implementation

[0035] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed merely to enable those skilled in the art to better understand and implement the subject matter described herein, and are not intended to limit the scope, applicability, or examples set forth in the claims. The function and arrangement of the elements discussed may be changed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the various examples. For example, the described methods may be performed in a different order than described, and steps may be added, omitted, or combined. Furthermore, features described in some examples may be combined in other examples.

[0036] As used herein, the term "comprising" and its variations are open terms meaning "including but not limited to". The term "based on" means "at least partially based on". The terms "one embodiment" and "an embodiment" mean "at least one embodiment". The term "another embodiment" means "at least one other embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other definitions, whether explicit or implicit, may be included below. Unless explicitly indicated by the context, the definition of a term shall remain consistent throughout the specification.

[0037] It should be noted that the terms "upper," "lower," "inner," and "outer" appearing in the description of this specification are used to indicate the orientation or positional relationship based on the drawings, or the orientation or positional relationship in which the product of this utility model is usually placed when in use. They are only for the convenience of description and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0038] An inverter according to an embodiment of the present invention will now be described with reference to the accompanying drawings.

[0039] Figure 2A side view of an inverter 200 according to an embodiment of the present invention is shown.

[0040] like Figure 2 As shown, inverter 200 may include a housing for providing support for the inverter assembly. The housing may include a housing body structure and a housing top cover 260. The housing body structure may include a housing bottom plate and housing side plates for providing support for the inverter assembly. In some examples, the housing body structure may be manufactured using a one-piece die-casting process, thereby increasing the rigidity and strength of the housing body structure.

[0041] Within the housing, the inverter 200 may include, from bottom to top, a heat sink 210, power devices / power modules (collectively referred to as "power devices" hereinafter), an electromagnetic shielding plate 230, and a printed circuit board assembly (PCBA) 240. The heat sink 210 may be mounted on the base plate of the inverter 200 housing and is arranged to contact the surface of the power devices away from the electromagnetic shielding plate 230 for heat dissipation during inverter operation. In some examples, the heat sink 210 may be implemented using heat sink fins. In some examples, the heat sink 210 may be implemented as a cooling system. The cooling system may, for example, include a cooling plate, cooling pipes, or a cooling assembly system consisting of a cooling plate, cooling pipes, and heat sink fins.

[0042] A power device may include one or more power devices. Figure 2 In the example, three power devices 220-1, 220-2, and 220-3 are shown. In other embodiments, more or fewer power devices may be included. Power devices are used to perform unidirectional power conversion from DC to AC or bidirectional power conversion between DC and AC. Examples of implementations of power devices may include, but are not limited to, bipolar junction transistors (BJTs), insulated-gate bipolar transistors (IGBTs), and metal-oxide-semiconductor field-effect transistors (MOSFETs). In some examples, power devices may be implemented using silicon carbide (SiC) semiconductor devices, for example. In some embodiments, power devices may be formed with the same device height.

[0043] PCBA 240 may include a printed circuit board and power conversion auxiliary circuitry disposed on the printed circuit board. The printed circuit board may be formed as a multilayer printed circuit board, and the power conversion auxiliary circuitry may be disposed on the upper and lower surfaces of the printed circuit board, respectively. The power conversion auxiliary circuitry is used to assist power devices in performing power conversion. Examples of power conversion auxiliary circuitry may include, but are not limited to, power conversion drive circuitry, power conversion control circuitry, filtering and output circuitry, detection and protection circuitry, auxiliary power supply circuitry, communication and interface circuitry, and / or heat dissipation and thermal management circuitry.

[0044] The power conversion drive circuit provides the drive signals required by the power devices to turn them on and off. For example, the power conversion drive circuit may include a gate drive circuit. The power conversion control circuit provides the control signals required by the power devices, such as control signals for controlling the switching timing and duty cycle of the power devices. The filtering and output circuit filters out high-frequency switching noise to output a noise-free sine wave signal. The detection and protection circuit monitors the inverter's operating status in real time and triggers protection mechanisms in case of abnormal operation. The auxiliary power supply circuit provides low-voltage power to the power conversion drive circuit and power conversion control circuit. The communication and interface circuit is used for human-machine interaction and remote monitoring. The heat dissipation and thermal management circuit ensures that the power devices operate within a safe temperature range.

[0045] Each power conversion auxiliary circuit can be composed of different types of electrical components (hereinafter referred to as "power conversion auxiliary circuit components"), such as inductors, capacitors, transistors, MOSFETs, transformer assemblies, etc. It should be noted that in this specification, "electrical components" of a power conversion auxiliary circuit can refer to the power conversion auxiliary circuit itself, individual constituent electrical components of the power conversion auxiliary circuit, or assemblies of electrical components. The performance degradation of these electrical components varies in the presence of electromagnetic interference. Based on the degree of degradation of electrical component performance caused by electromagnetic interference, electrical components can be classified into electromagnetic interference-sensitive components and electromagnetic interference-insensitive components, for example, Figure 2 The circuit includes an electromagnetic interference-insensitive element 251 and an electromagnetic interference-sensitive element 253. Furthermore, the electrical components of the power conversion auxiliary circuit can have different component heights.

[0046] An electromagnetic shielding plate 230 is disposed between the power devices and the PCBA 240 to shield or reduce electromagnetic interference from the power devices to the electrical components on the PCBA 240. Furthermore, the electromagnetic shielding plate 230 can ensure the integrity of low-power signals on the PCBA 240 by preventing noise and crosstalk from high-power circuits in the inverter. Moreover, the electromagnetic shielding plate 230 can also provide thermal protection for the PCBA 240 to prevent overheating of the PCBA 240 caused by heat generated by the power devices, thereby affecting the electrical performance of the electrical components on the PCBA 240.

[0047] The electromagnetic shielding plate 230 is typically a few millimeters thick, and a recessed space is formed on the surface of the electromagnetic shielding plate 230 near the PCBA 240. During inverter assembly, power conversion auxiliary circuitry components on the surface of the PCBA 240 near the electromagnetic shielding plate 230 can be inserted into the recessed space of the electromagnetic shielding plate. In some examples, when inserting the power conversion auxiliary circuitry components into the recessed space of the electromagnetic shielding plate, the components can be positioned as close as possible to the bottom inner wall of the recessed space without causing electrical safety issues.

[0048] In some embodiments, the recessed space can be formed such that after the power conversion auxiliary circuit elements on the surface of the printed circuit board of PCBA240 near the electromagnetic shielding plate 230 are inserted into the recessed space of the electromagnetic shielding plate, the spacing between PCBA240 and the power devices is within a predetermined spacing range. The predetermined spacing range can be determined in advance. For example, the predetermined spacing range can be determined in advance according to design requirements, or according to electrical safety requirements parameters, the permeability and shape parameters of the electromagnetic shielding plate.

[0049] In some embodiments, a corresponding recessed space can be formed on the side of the electromagnetic shielding plate 230 near the PCBA 240 for each power conversion auxiliary circuit element on the side of the printed circuit board of the PCBA 240 near the electromagnetic shielding plate 230. The recessed depth of each recessed space can be the same or different. In some examples, the recessed depth of each recessed space can be determined according to the element height of the corresponding power conversion auxiliary circuit element.

[0050] In some embodiments, recessed spaces can be formed on the side of the electromagnetic shielding plate 230 near the PCBA 240 for some power conversion auxiliary circuit elements on the side of the printed circuit board of the PCBA 240 near the electromagnetic shielding plate 230. For example, a recessed space can be formed at a position corresponding to a first power conversion auxiliary circuit element among the power conversion auxiliary circuit elements on the side of the printed circuit board near the electromagnetic shielding plate. The first power conversion auxiliary circuit element includes power conversion auxiliary circuit elements with a component height greater than a predetermined component height. The predetermined component height can be predetermined according to design requirements. In this way, all power conversion auxiliary circuit elements with a component height greater than the predetermined component height can be inserted into the corresponding recessed spaces, thereby further reducing the spacing between the PCBA 240 and the power devices.

[0051] In some embodiments, the first power conversion auxiliary circuit element may be an electromagnetic interference-insensitive element, and the element height of the first power conversion auxiliary circuit element exceeds the element height of all electromagnetically sensitive elements on the surface of the printed circuit board near the electromagnetic shielding plate 230. In this way, corresponding recessed spaces can be formed only for electromagnetic interference-insensitive elements on the surface of the printed circuit board near the electromagnetic shielding plate 230 whose element height exceeds a predetermined element height and all electromagnetic interference sensitive elements, thereby preventing electromagnetic interference sensitive elements on the surface of the printed circuit board near the electromagnetic shielding plate 230 from being too close to the power devices and causing a significant impact on performance.

[0052] In some embodiments, the circuit elements of the power conversion auxiliary circuit on the surface of the printed circuit board near the electromagnetic shielding plate 230 can be rearranged so that the positions of the first power conversion auxiliary circuit elements on the printed circuit board are staggered from the positions of the power devices. With this component arrangement, the thickness of the electromagnetic shielding plate directly above the power devices can be maintained, thereby reducing the degradation of the electromagnetic shielding performance caused by thinning of certain areas of the electromagnetic shielding plate.

[0053] In some embodiments, the recessed space can be entirely formed as a through-hole, for example. Figure 3 A top view of an electromagnetic shielding plate 310 according to an embodiment of the present invention is shown, and... Figure 4 It shows Figure 3 The diagram shows a cross-sectional view of the electromagnetic shielding plate. Figure 3 In the example, the recessed spaces are all formed as through holes, and the other parts of the electromagnetic shielding plate 310 are integrally formed.

[0054] In some embodiments, such as Figure 5As shown, some recessed spaces can be formed as through-type recessed spaces, and some recessed spaces can be formed as non-through-type recessed spaces, such as grooves. The recess depth of the non-through-type recessed space can be determined according to the component height of the corresponding power conversion auxiliary circuit element. In some embodiments, the recess depth of the non-through-type recessed space can be determined according to the component height of the corresponding power conversion auxiliary circuit element, the electromagnetic interference parameters of the power device, and the permeability of the electromagnetic shielding plate.

[0055] In some embodiments, such as Figure 6 As shown, all recessed spaces can be formed as non-through recessed spaces, and these non-through recessed spaces can have different recess depths. In this case, the recess depth of each non-through recessed space can be determined based on the component height of the corresponding power conversion auxiliary circuit element. Alternatively, the recess depth of each non-through recessed space can be determined based on the component height of the corresponding power conversion auxiliary circuit element, the electromagnetic interference parameters of the power device, and the permeability of the electromagnetic shielding plate.

[0056] In some embodiments, the electromagnetic shielding plate 230 can be made of a high-permeability material. In this way, the high permeability of the electromagnetic shielding plate 230 can compensate for the degradation of the electromagnetic shielding performance caused by thinning in certain areas of the electromagnetic shielding plate. In some examples, the electromagnetic shielding plate can be made of a material with a permeability not less than a first permeability. The first permeability can be a predetermined permeability. The first permeability can be measured using relative permeability, and the value of the first permeability can be, for example, 100. The material used to make the electromagnetic shielding plate 230 can include, but is not limited to, nickel ferrite (N... i Fe2O4) materials, manganese zinc ferrite (Mn x Zn y Materials such as Fe2O4.

[0057] In some embodiments, the first permeability can be determined based on the electromagnetic interference parameters of the power device and the spacing between the printed circuit board assembly and the power device. In this way, given the spacing between the printed circuit board assembly and the power device according to design requirements, the electromagnetic shielding plate can be fabricated using a material with suitable permeability, reducing the degradation of the electromagnetic shielding performance caused by thinning of certain areas of the electromagnetic shielding plate.

[0058] In some embodiments, the degradation of electromagnetic shielding performance due to thinning of certain areas of the electromagnetic shielding plate can be minimized by coordinating the materials used in the electromagnetic shielding plate, the depth of the recessed space, and the spacing between the printed circuit board assembly and the power device.

[0059] In some embodiments, the electromagnetic interference parameters of a power device may include the switching frequency and switching speed of the power device. The switching frequency of a power device refers to the number of times the power device completes a full cycle of turn-on → turn-off → turn-on within a unit of time (typically 1 second). The switching speed of a power device refers to the time required for the power device to switch from turn-on to turn-off or from turn-off to turn-on in a single switching action.

[0060] In some embodiments, to further compensate for the loss of shielding performance due to the electromagnetic shielding plate, an electromagnetic interference (EMI) shielding enhancement material can be coated onto the surface of the power conversion auxiliary circuit elements on the surface of the printed circuit board near the electromagnetic shielding plate. Examples of EMI shielding enhancement materials include, but are not limited to, copper, aluminum, silver, nickel-iron alloys, manganese-zinc ferrite, nickel-zinc ferrite, graphene films, and sodium-carbon nanotube composite materials. In some examples, EMI shielding enhancement material can be coated onto a portion of the power conversion auxiliary circuit elements on the surface of the printed circuit board near the electromagnetic shielding plate. For example, EMI shielding enhancement material can be coated onto the surface of a first power conversion auxiliary circuit element on the surface of the printed circuit board near the electromagnetic shielding plate, or EMI shielding enhancement material can be coated onto the surface of an electromagnetic interference sensitive element on the surface of the power conversion auxiliary circuit elements on the surface of the printed circuit board near the electromagnetic shielding plate.

[0061] In some embodiments, an electric vehicle may also be provided. The electric vehicle includes an inverter as described above according to embodiments of this specification.

[0062] The specific embodiments described above with reference to the accompanying drawings are exemplary embodiments, but do not represent all embodiments that can be implemented or fall within the scope of the claims. The term "exemplary" as used throughout this specification means "serving as an example, instance, or illustration" and does not imply that it is "preferred" or "advantageous" compared to other embodiments. Specific details are included to provide an understanding of the described techniques. However, these techniques can be practiced without these specific details. In some instances, well-known structures and apparatuses are shown in block diagram form to avoid obscuring the concepts of the described embodiments.

[0063] The foregoing description of this disclosure is provided to enable any person skilled in the art to implement or use this disclosure. Various modifications to this disclosure will be apparent to those skilled in the art, and the general principles defined herein can be applied to other variations without departing from the scope of this disclosure. Therefore, this disclosure is not limited to the examples and designs described herein, but is consistent with the widest scope of the principles and novel features disclosed herein.

Claims

1. An inverter, characterized in that, The inverter includes: At least one power device is used to perform unidirectional power conversion from DC to AC or bidirectional power conversion between DC and AC. Printed circuit board assembly, the printed circuit board assembly including a printed circuit board and power conversion auxiliary circuitry disposed on the printed circuit board; and An electromagnetic shielding plate is disposed between the power device and the printed circuit board assembly, and a recessed space is formed on the surface of the electromagnetic shielding plate near the printed circuit board assembly. The power conversion auxiliary circuit elements on the surface of the printed circuit board near the electromagnetic shielding plate are arranged to be inserted into the recessed space of the electromagnetic shielding plate.

2. The inverter as described in claim 1, characterized in that, The recessed space is formed at a position corresponding to the first power conversion auxiliary circuit element in the power conversion auxiliary circuit elements on the surface of the printed circuit board near the electromagnetic shielding plate, and the element height of the first power conversion auxiliary circuit element is greater than a predetermined element height.

3. The inverter as described in claim 2, characterized in that, The recessed space includes at least two recessed spaces. The depth of each recessed space is determined according to the component height of the corresponding first power conversion auxiliary circuit element, or the depth of each recessed space is determined according to the component height of the corresponding first power conversion auxiliary circuit element, the electromagnetic interference parameters of the power device, and the magnetic permeability of the electromagnetic shielding plate.

4. The inverter as described in claim 2, characterized in that, The first power conversion auxiliary circuit element is positioned on the printed circuit board in a manner that is offset from the position of the power device.

5. The inverter as described in claim 2, characterized in that, The first power conversion auxiliary circuit element is an electromagnetic interference insensitive element, and the element height of the first power conversion auxiliary circuit element exceeds the element height of all electromagnetic interference sensitive elements on the surface of the printed circuit board near the electromagnetic shielding plate.

6. The inverter as described in claim 1, characterized in that, The electromagnetic shielding plate is made of a material with a permeability not less than a first permeability.

7. The inverter as described in claim 6, characterized in that, The first permeability is determined based on the electromagnetic interference parameters of the power device and the spacing between the printed circuit board assembly and the power device.

8. The inverter as described in claim 7, characterized in that, The electromagnetic interference parameters include the switching frequency and switching speed of the power devices.

9. The inverter as described in claim 1, characterized in that, Some or all of the recessed spaces are formed as through-type recessed spaces.

10. The inverter as claimed in claim 1, characterized in that, The surfaces of the power conversion auxiliary circuit elements on the side of the printed circuit board near the electromagnetic shielding plate are coated with electromagnetic interference shielding enhancement material. The surface of the first power conversion auxiliary circuit element on the side of the printed circuit board near the electromagnetic shielding plate is coated with electromagnetic interference shielding enhancement material. The height of the first power conversion auxiliary circuit element is greater than a predetermined element height. Alternatively, the surface of the electromagnetic interference sensitive element on the side of the printed circuit board near the electromagnetic shielding plate is coated with electromagnetic interference shielding enhancement material.

11. An electric vehicle, characterized in that, The electric vehicle includes an inverter as described in any one of claims 1 to 10.

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