Vehicle inverter

Abstract

The application provides a vehicle inverter, which comprises a printed circuit board, a DC busbar unit and an AC busbar unit. The printed circuit board comprises power devices and a gate drive circuit for driving the power devices to be turned on or turned off. The DC busbar unit comprises a first DC busbar welded on a first side of the printed circuit board. The first DC busbar comprises a plurality of DC busbar combinations, each of which comprises a DC positive busbar and a DC negative busbar. At least part of the area between the DC positive busbar and the DC negative busbar is arranged in an interlaced manner. The AC busbar unit is welded on a second side of the printed circuit board. The AC busbar unit is connected to output terminals of the power devices and a load, respectively, so as to drive the load based on the turning on or turning off of the power devices. The power characteristics of the power semiconductor in the inverter can be effectively improved.

Description

Technical Field

[0001] This application relates to the field of electronic vehicle technology, and more particularly to a vehicle inverter. Background Technology

[0002] In the development of modern electric vehicles, vehicle inverters, as key power electronic devices, play an important role in converting direct current (DC) into alternating current (AC) to drive electric motors.

[0003] Currently, the power core design of vehicle inverters typically includes a power PCB (Printed Circuit Board) and a driver PCB, resulting in a large physical space. Furthermore, the two PCBs need to be connected via connectors or wiring harnesses, leading to a relatively large overall inverter size and making it difficult to achieve high power density. In addition, longer wires or connectors increase the equivalent series inductance (ESL), resulting in a higher ESL in the inverter. A higher ESL not only limits the inverter's switching speed but may also cause electromagnetic interference (EMI) problems, thus affecting the system's dynamic characteristics and overall efficiency.

[0004] Therefore, there is an urgent need to develop a compact vehicle inverter to improve the inverter's power density or reduce its ESL. Utility Model Content

[0005] This application provides a vehicle inverter to at least solve one of the above-mentioned technical problems.

[0006] In a first aspect, this application provides a vehicle inverter, comprising:

[0007] A printed circuit board, the printed circuit board including power devices and gate drive circuits for driving the power devices to be turned on or off; the power devices include an upper bridge power device and a lower bridge power device;

[0008] A DC bus unit, the DC bus unit includes a first DC bus soldered on a first side of the printed circuit board, the first DC bus includes a DC positive bus and a DC negative bus, the DC positive bus is connected to the first electrode and the DC positive input terminal of the upper bridge power device respectively, and the DC negative bus is connected to the second electrode and the DC negative input terminal of the lower bridge power device;

[0009] An AC busbar unit is soldered to the second side of the printed circuit board. It is connected to the second electrode of the upper bridge power device, the first electrode of the lower bridge power device, and the load, respectively, so as to drive the load based on the on or off state of the power device.

[0010] In one embodiment, at least a portion of the area between the DC positive busbar and the DC negative busbar is arranged in an overlapping configuration; the DC busbar unit further includes:

[0011] An insulating film material is disposed in the overlapping area between the DC positive busbar and the DC negative busbar;

[0012] The insulating film material is configured to provide electrical insulation for the overlapping portion between the DC positive busbar and the DC negative busbar.

[0013] In one embodiment, the gate driving circuit is disposed on the upper surface layer of the printed circuit board, and the power device is embedded in the inner layer of the printed circuit board; a shielding layer for shielding electromagnetic interference is included between the upper surface layer and the inner layer.

[0014] The lower surface layer of the printed circuit board is provided with a thermally conductive layer, and the material of the thermally conductive layer includes a thermally conductive interface material.

[0015] In one implementation, it further includes:

[0016] A heat sink is provided, wherein the printed circuit board is mounted on the heat sink via the thermally conductive layer to dissipate heat from the electronic components on the printed circuit board.

[0017] In one implementation, it further includes:

[0018] A housing disposed below the printed circuit board includes a coolant channel configured to cool the printed circuit board and the DC link capacitors corresponding to the DC bus unit.

[0019] In one embodiment, the DC bus unit further includes a second DC bus disposed on the housing and located below the first DC bus. The second DC bus is used to connect to a DC power supply and has a positive interface for connecting to the DC power supply and a negative interface for connecting to the DC power supply.

[0020] The DC positive busbar is connected to the DC positive input terminal through the DC positive interface of the second DC busbar; the DC negative busbar is connected to the DC negative input terminal through the DC negative interface of the second DC busbar.

[0021] In one embodiment, the printed circuit board includes:

[0022] A first substrate, wherein a first chip packaging unit and a second chip packaging unit are embedded in the first substrate, the first chip packaging unit includes the upper bridge power device, and the second chip packaging unit includes the lower bridge power device;

[0023] A second substrate disposed on the upper layer of the first substrate, the upper surface of the second substrate including the gate driving circuit, the gate driving circuit including a first gate driving circuit and a second gate driving circuit;

[0024] A transmission channel penetrating the first substrate and the second substrate, the transmission channel including a first transmission channel and a second transmission channel, the first transmission channel being configured to transmit the drive signal of the first gate drive circuit to the upper bridge power device to drive the upper bridge power device to turn on or off, and the second transmission channel being configured to transmit the drive signal of the second gate drive circuit to the lower bridge power device to drive the lower bridge power device to turn on or off.

[0025] In one embodiment, the first transmission channel is connected to the first control electrode of the upper bridge power device, and the second transmission channel is connected to the second control electrode of the lower bridge power device; wherein...

[0026] The first control electrode is led out to the upper surface of the second substrate through the first transmission channel, so that the first control electrode is connected to the first gate driving circuit to receive the driving signal transmitted by the first gate driving circuit.

[0027] The second control electrode is led out to the upper surface of the second substrate through the second transmission channel, so that the second control electrode is connected to the second gate driving circuit to receive the driving signal transmitted by the second gate driving circuit.

[0028] In one embodiment, the transmission channel further includes a third transmission channel connected to the first electrode of the upper bridge power device, a fourth transmission channel connected to the upper end of the first metal support block, a fifth transmission channel connected to the second electrode of the lower bridge power device, and a sixth transmission channel connected to the upper end of the second metal support block; wherein, the first metal support block is a conductive support component configured to be embedded in the first substrate and supporting the upper bridge power device in the first chip packaging unit, and the second metal support block is a conductive support component configured to be embedded in the first substrate and supporting the lower bridge power device in the second chip packaging unit;

[0029] The first electrode of the upper bridge power device is led out to the surface of the printed circuit board through the second transmission channel, so that the first electrode is connected to the DC positive busbar; the second electrode of the upper bridge power device is led out to the surface of the printed circuit board through the fourth transmission channel, so that the second electrode of the upper bridge power device is connected to the AC busbar.

[0030] The second electrode of the lower bridge power device is led out to the surface of the printed circuit board through the fifth transmission channel, so that the second electrode is connected to the DC negative busbar; the first electrode of the lower bridge power device is led out to the surface of the printed circuit board through the sixth transmission channel, so that the first electrode of the lower bridge power device is connected to the AC busbar.

[0031] In one embodiment, the transmission channel is a micropore with a metal coating on the inside, and the number of micropores is determined based on a predefined current carrying requirement.

[0032] In one embodiment, the transmission channel further includes:

[0033] A low-voltage connector is disposed on the printed circuit board and connected to the gate drive circuit. The low-voltage connector is configured to receive control commands from an external control board and send drive signals to the gate drive circuit.

[0034] The vehicle inverter provided in this application integrates the drive circuit and power devices on a single PCB board. By soldering DC and AC buses to both sides of the PCB board and using a design where the positive and negative DC buses are partially overlapped, the physical space is significantly reduced. This shortens the signal transmission path between the drive circuit and power devices and reduces ESL problems caused by factors such as excessively long wiring harnesses. As a result, the power characteristics of the power semiconductors in the inverter are improved, and the overall system stability and weight reduction are achieved. Attached Figure Description

[0035] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0036] Figure 1 This is a schematic diagram of the structure of the vehicle inverter provided in the embodiments of this application;

[0037] Figure 2 yes Figure 1 A schematic diagram of the structure of the printed circuit board 100;

[0038] Figure 3 This is one of the cross-sectional views of the vehicle inverter provided in the embodiments of this application;

[0039] Figure 4 This is a second cross-sectional view of the vehicle inverter provided in the embodiments of this application.

[0040] Reference numerals: 1000 - Vehicle inverter; 1100 - Printed circuit board; 1110 - First substrate; 1111 - First chip packaging unit; 1112 - Second chip packaging unit; 11111 - First metal support block; 11121 - Second metal support block; 1120 - Second substrate; 1131 - First transmission channel; 1132 - Second transmission channel; 1133 - Third transmission channel; 1134 - Fourth transmission channel; 1135 - Fifth transmission channel; 1136 - Sixth transmission channel; 1140 - Shielding layer; 1150 - Thermal conductive layer; 1160 - Low-voltage connector; 1200 - AC busbar unit; 1300 - DC busbar unit; 1310 - First DC busbar; 1311 - DC positive busbar; 1312 - DC negative busbar; 1313 - Insulating film material; 1400 - Heat sink; 1500 - Housing; 1510 - Coolant channel.

[0041] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0042] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0043] The terms "upper" and "lower," etc., indicating orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are used only for the convenience of describing this application and simplifying the 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, and therefore should not be construed as a limitation of this application. Furthermore, in the description of this application, when it is said that a device is "connected" to another device, this includes not only direct connection but also indirect connection through other elements.

[0044] It should be noted that, unless otherwise specified, the embodiments of this application and the features in different embodiments can be combined with each other.

[0045] Figures 1-4 This is a structural diagram of the vehicle inverter according to an embodiment of this application, as shown below. Figures 1-4 As shown, the vehicle inverter 1000 may include a printed circuit board 1100, an AC busbar unit 1200, and a DC busbar unit 1300.

[0046] The printed circuit board 1100 includes an upper bridge power device a1, a lower bridge power device a2, a first gate drive circuit b1 for driving the upper bridge power device a1 to turn on or off, and a second gate drive circuit b2 for driving the lower bridge power device a2 to turn on or off.

[0047] The DC bus unit 1300 includes a first DC bus 1310 soldered on a first side of the printed circuit board 1100. The first DC bus includes a DC positive bus 1311 and a DC negative bus 1312. Optionally, at least a portion of the DC positive bus 1311 and the DC negative bus 1312 are arranged in an overlapping manner. The DC positive bus 1311 is connected to the first electrode and the DC positive input terminal of the upper bridge power device a1, and the DC negative bus is connected to the second electrode and the DC negative input terminal of the lower bridge power device a2.

[0048] The AC busbar unit 1200 is soldered to the second side of the printed circuit board 1100. The AC busbar unit 1200 is connected to the second electrode of the upper bridge power device a1, the first electrode of the lower bridge power device a2, and the load, respectively, so as to drive the load based on the on or off of the power device.

[0049] In related technologies, two PCBs, a power PCB and a driver PCB, are deployed and connected by wire harnesses or connectors. In wire harness connections, appropriate wire materials and specifications must be selected, and connector terminals must be installed at both ends of the wires. During wire harness assembly, multiple wires are typically bundled together and secured with cable ties or sheaths before connecting both ends of the harness to connectors on their respective PCBs. This results in an extended signal transmission path. This connection method leads to a larger physical distance between the PCBs, and the extended signal transmission path introduces additional equivalent series inductance (ESL), which can easily cause signal delay and distortion. Especially under high-frequency operation, this can severely degrade the dynamic characteristics of power semiconductors, thereby affecting the overall performance and efficiency of the inverter.

[0050] In direct connector connections, the pins (i.e., connector leads) are typically inserted directly into the connector. This means that pins on one PCB are inserted into corresponding holes on another PCB to achieve signal and power transmission between the two PCBs. This method is prone to unstable connections and increases the risk of poor contact. This is especially true during the operation of electric vehicles, where vibrations or mechanical stresses are significant. This not only results in a larger overall physical space for electronic components but also affects stability.

[0051] In this embodiment, by integrating the drive circuit and power devices into a single PCB board, and by soldering DC and AC busbars to both sides of the PCB board, and by using a design where the positive and negative DC busbars overlap in certain areas, the physical space is significantly reduced. This also shortens the signal transmission path between the drive circuit and the power devices, and reduces ESL problems caused by factors such as excessively long wire harnesses. As a result, the power characteristics of the power semiconductors are improved, and the overall stability and weight reduction of the system are achieved.

[0052] It should be noted that the first and second sides in this embodiment can be two opposite sides of a printed circuit board. The number of DC busbar combinations in this embodiment can be determined according to the system topology. For example, if the inverter is a three-phase bridge structure, it uses three DC busbar combinations (three positive DC buses and three negative DC buses). It is understood that the AC busbar unit can include U-phase busbars, V-phase busbars, and W-phase busbars, which will not be elaborated further here.

[0053] In one implementation, such as Figure 2 As shown, the printed circuit board 1100 may include: a first substrate 1110, in which a first chip packaging unit 1111 and a second chip packaging unit 1112 are embedded, the first chip packaging unit 1111 including the first power device a1, and the second chip packaging unit 1112 including the second power device a2; a second substrate 1120 disposed on the upper layer of the first substrate 1110, the upper surface of the second substrate 1120 including the first gate driving circuit b1 and the second gate driving circuit b2; and a transmission channel penetrating the first substrate 1110 and the second substrate 1120, the transmission channel including a first transmission channel 1131 and a second transmission channel 1132, the first transmission channel 1131 being configured to transmit the driving signal of the first gate driving circuit b1 to the upper bridge power device a1 to drive the upper bridge power device a1 to turn on or off, and the second transmission channel 1132 being configured to transmit the driving signal of the second gate determining circuit b2 to the lower bridge power device a2 to determine whether the lower bridge power device a2 is turned on or off.

[0054] Optionally, combined Figure 2 and Figure 3 As shown, the upper surface of the second substrate 1120 also includes a driving power supply c1 connected to the first driving circuit b1, which provides a power supply voltage to the first driving circuit b1. Additionally, a driving power supply c2 is connected to the second driving circuit b2, which provides a power supply voltage to the second driving circuit b2.

[0055] In this embodiment, a chip packaging unit containing a power chip is embedded in the first substrate. This chip packaging unit can employ Chip on Board (CoB) technology, meaning it is directly embedded in the first substrate to reduce the overall system size and weight, while improving thermal conductivity and electrical performance. The power chip can be a structure containing only power devices, or it can include circuitry other than power devices, such as interface circuitry. Through this embedded chip packaging unit design, the chip is surrounded by the substrate material, providing better mechanical support and protection. This allows the chip to better resist external mechanical stress and vibration, thereby reducing the risk of damage caused by physical impact or vibration. Furthermore, the embedded design allows for tighter contact between the chip and the substrate, enabling more efficient heat transfer from the chip to the substrate, where it is diffused and dissipated through the substrate material.

[0056] By vertically mounting the second substrate on the first substrate, a more compact design is achieved. Simultaneously, the drive circuit is positioned on the upper surface of the second substrate, effectively shortening the signal transmission path between the drive circuit and the power devices while achieving physical and electrical isolation from the power devices in the first substrate. This reduces electromagnetic interference (EMI) caused by the high voltage or current generated by the power devices, protecting the sensitive drive circuit from potential electrical noise and overvoltage in PCB integrated designs. Furthermore, power devices typically generate significant heat; placing the drive circuit on the upper surface of the second substrate reduces direct heat conduction into the drive circuit, preventing performance degradation or damage due to overheating.

[0057] As can be seen, compared with the method of separately deploying the driver board and power board and connecting them through connectors in related technologies, the integrated PCB board provided in this embodiment, by utilizing the substrate stack-up design, the design method of the driver circuit and power device (chip embedding and driver circuit upper surface layout), and the transmission channel method that runs through the substrate, reduces physical space, shortens the signal transmission path between the driver circuit and power device, effectively enhances the mechanical strength and thermal management capability of the system, and reduces electromagnetic interference between the power device and the driver circuit to a certain extent, thereby improving the overall stability and reliability of the system.

[0058] In one embodiment, the first gate driving circuit b1 and the second gate driving circuit b2 are disposed on the upper surface layer of the printed circuit board 1100, and the upper bridge power device a1 and the lower bridge power device a2 are embedded in the inner layer of the printed circuit board 1100; a shielding layer 140 for shielding electromagnetic interference is included between the upper surface layer and the inner layer; a thermally conductive layer is disposed on the lower surface layer of the printed circuit board, and the material of the thermally conductive layer includes a thermally conductive interface material.

[0059] In related technologies, since the drive circuit and power devices use two PCBs, the signal needs to be transmitted between the two boards. The long transmission path may lead to signal attenuation and reflection, increasing the risk of EMI. To solve this problem, shielding material is usually added between the two PCBs that respectively carry the drive circuit and the power devices to reduce the impact of electromagnetic interference on circuit performance. However, adding shielding material between the two PCBs increases the complexity of the manufacturing process: precise alignment and installation are required to ensure shielding effectiveness and mechanical stability, and the shielding material occupies additional space, which will increase the size of the entire device and is not conducive to miniaturization design. Obviously, the above method not only increases material and manufacturing costs, but may also lead to poor shielding effectiveness and failure to fully suppress high-frequency interference.

[0060] In this embodiment, by integrating the drive circuit and power devices onto the same PCB board, this design effectively shortens the signal transmission path and significantly reduces signal delay and distortion. Simultaneously, by separately placing the drive circuit and power devices on the surface and inner layers of the PCB board, respectively, and placing a shielding layer between the surface and inner layers, this EMI shielding layer integrated on the same PCB board can more tightly isolate electromagnetic interference. Based on the original layer stack, by adding a shielding layer in the spatial region of the stack, the EMI shielding effect can be achieved, while reducing manufacturing costs and complexity.

[0061] For example, in conjunction with the above embodiments, the first substrate 1110 may be disposed on the upper surface layer of the printed circuit board 1100, the second substrate 1120 may be disposed on the inner layer of the printed circuit board 1100, a shielding layer 1140 may be disposed between the first substrate 1110 and the second substrate 1120, and a thermally conductive layer 1150 may be disposed below the second substrate 1120.

[0062] In one embodiment, the vehicle inverter 1000 may further include a heat sink 1400, wherein the printed circuit board 1100 is mounted on the heat sink 1400 via the thermally conductive layer 1150 to dissipate heat from the electronic components on the printed circuit board 1100.

[0063] In this embodiment, heat dissipation is achieved using a thermal interface material (TIM) in the thermally conductive layer. TIM is a material specifically designed to improve thermal conductivity, typically possessing high thermal conductivity and good flexibility. In this embodiment, a TIM material with electrical insulation properties can be used. By applying TIM, the thermal resistance between electronic components and the heat sink can be significantly reduced, thereby improving thermal conductivity and simultaneously achieving electrical insulation between the printed circuit board and the heat sink.

[0064] In one embodiment, the first transmission channel 1131 is connected to the first control electrode of the power device a1, and the second transmission channel 1132 is connected to the second control electrode of the power device a2; wherein...

[0065] The first control electrode is led out to the upper surface of the second substrate through the first transmission channel 1131, so that the first control electrode is connected to the first gate driving circuit b1 to receive the driving signal transmitted by the first gate driving circuit b1.

[0066] The second control electrode is led out to the upper surface of the second substrate through the second transmission channel 1132, so that the second control electrode is connected to the second gate driving circuit b2 to receive the driving signal transmitted by the second gate driving circuit b2.

[0067] For example, the power device may be an insulated gate bipolar transistor (IGBT) or a silicon carbide metal-oxide-semiconductor field-effect transistor (SiC MOSFET). In some embodiments, it may also be a giant transistor (GTR), a bipolar junction transistor (BJT), etc.

[0068] Taking a SiC MOSFET as an example, the power device includes three electrodes: the gate (corresponding to the control electrode, which forms an electric field by applying voltage to control the conduction state between the source and drain), the source (corresponding to the first electrode, the current input terminal as the low potential terminal of the circuit), and the drain (corresponding to the second electrode, the current output terminal as the high potential terminal of the circuit). In some embodiments, the source may correspond to the second electrode and the drain to the first electrode; this embodiment does not impose any particular limitation on this.

[0069] In this embodiment, the gate is led out to the upper surface of the second substrate using a first transmission channel, enabling it to connect to the driving circuit. In this way, the driving circuit can transmit control signals to the gate of the power device through the transmission channel, thereby efficiently turning the power device on or off. Thus, the SiC MOSFET can effectively control current flow, providing efficient power conversion and management. Simultaneously, the reliable connection to the driving circuit via the first transmission channel shortens the transmission distance and further improves the power dynamic characteristics.

[0070] In one embodiment, the transmission channel may further include a third transmission channel 1133 connected to the first electrode of the upper bridge power device a1, a fourth transmission channel 1134 connected to the upper end of the first metal support block 11111, a fifth transmission channel 1135 connected to the second electrode of the lower bridge power device a2, and a sixth transmission channel 1136 connected to the upper end of the second metal support block 11121; wherein the first metal support block 11111 is a conductive support component in the first chip packaging unit 1111 configured to be embedded in the first substrate 1110 and supporting the upper bridge power device a1, and the second metal support block 11121 is a conductive support component in the second chip packaging unit 1112 configured to be embedded in the first substrate 1110 and supporting the lower bridge power device a2;

[0071] The first electrode of the upper bridge power device a1 is led out to the surface of the printed circuit board 1100 through the second transmission channel 1132, so that the first electrode of the upper bridge power device a1 is connected to the DC positive busbar 1311; the second electrode of the upper bridge power device a1 is led out to the surface of the printed circuit board through the fourth transmission channel 1134, so that the second electrode of the upper bridge power device a1 is connected to the AC busbar unit 1200.

[0072] The second electrode of the lower bridge power device a2 is led out to the surface of the printed circuit board through the fifth transmission channel 1135, so that the second electrode of the lower bridge power device a2 is connected to the DC negative busbar 1312; the first electrode of the lower bridge power device a2 is led out to the surface of the printed circuit board 1100 through the sixth transmission channel 1136, so that the first electrode of the lower bridge power device a2 is connected to the AC busbar unit 1200.

[0073] In this embodiment, the second substrate is disposed on the surface structure of the PCB board. The first and second electrodes can be led out to the upper surface of the second substrate, for example, they can be located on the side of the upper surface of the second substrate. As mentioned above, the DC positive bus and DC negative bus are soldered to the first side of the printed circuit board, and the AC bus unit is soldered to the second side of the printed circuit board. When the electrodes of the power device are led out, they can be combined with the led-out DC bus and AC bus to the corresponding side, which will not be elaborated further here.

[0074] It should be understood that the transmission channel layout in the accompanying drawings of this application embodiments is merely a possible example to facilitate understanding of the embodiments of this application, and is not intended to limit the embodiments of the present invention. For example, the internal wiring of the PCB board is not described in the drawings. The transmission channel may extend in a parallel direction to a first or second side of the PCB board, thereby enabling the electrodes of the power device to be led out to the relevant sides of the DC busbar and AC busbar soldered on the side of the PCB board. In addition, the transmission channel may not have wiring in the vertical direction. The wiring in the vertical direction shown in the drawings may be the transmission channel used for connection between other components.

[0075] Optionally, the first and second electrodes of the power device can be located on the front and back sides of the chip, respectively. One approach is to embed the chip within a metal support block on a first substrate. Since the metal support block is conductive, the electrodes on the back side of the chip can be led out, eliminating the need for a separate back-side design; the electrodes can be led out directly through the metal support block. Specifically, utilizing the connection between corresponding transmission channels (such as the fourth or sixth transmission channel) and the metal support block, the second electrode of the upper bridge power device can be led out from the metal support block through the fourth transmission channel to the surface layer of the PCB, i.e., the side position of the upper surface of the second substrate. An AC busbar unit is soldered to this side position. Another approach is to design a second transmission channel based on the front side of the chip (e.g., drilling holes on the front side, i.e., drilling holes upwards on the second substrate), leading out the first electrode on the front side through the second transmission channel. A corresponding transmission channel can also be designed based on the back side of the chip (e.g., drilling holes on the back side, i.e., drilling holes downwards on the second substrate), leading out the second electrode on the back side through this transmission channel. This embodiment does not particularly limit the specific method of electrode lead-out.

[0076] In the above solution, the flexible transmission channel design and the application of metal support blocks enable efficient lead-out and reliable connection of power device electrodes, thereby improving the flexibility of PCB design and manufacturing efficiency.

[0077] Optionally, the transmission channel can be a micropore with a metal coating on the inside, the number of which is determined based on a predefined current carrying requirement.

[0078] In this embodiment, the transmission channel is designed as copper-plated microvias (a low-impedance path for current within the transmission channel, thereby reducing power loss and signal attenuation). The number and diameter of the microvias can be determined based on predefined current-carrying requirements. These predefined current-carrying requirements can be calculated based on the specific current requirements of the device mounting the printed circuit board, allowing for the selection of an appropriate number and size of microvias. This ensures that the transmission channel can carry the required current without generating excessive heat or loss. In some embodiments, the number of microvias can also be flexibly adjusted according to the actual number of layers, thereby providing stable and efficient electrical connections in complex multilayer PCBs, adapting to different circuit design requirements, and improving the overall circuit performance and reliability.

[0079] In one implementation, combined with Figure 4 As shown, the DC bus unit 1300 further includes: an insulating film material 1313, which is disposed in the overlapping area between the DC positive bus 1311 and the DC negative bus 1312;

[0080] The insulating film material 1313 is configured to provide electrical insulation for the overlapping portion between the DC positive busbar 1311 and the DC negative busbar 1312.

[0081] As mentioned above, DC buses are used to transmit DC power. The DC positive and DC negative buses are arranged in an overlapping manner to reduce the equivalent series inductance (ESL), thereby optimizing power transmission performance. However, direct contact between the positive and negative buses may cause electrical faults such as short circuits, so insulation measures need to be installed in the overlapping area.

[0082] In this embodiment, an insulating film material is placed between the DC positive busbar and the DC negative busbar. This insulating film material has excellent electrical insulation properties, effectively preventing direct current conduction between the two. When the system is powered on, the DC positive busbar carries a positive potential, and the DC negative busbar carries a negative potential, creating a potential difference between them. The insulating film material, with its high resistivity, forms an electrical barrier at the overlapping area, ensuring that current flows only along a predetermined circuit path and preventing leakage or short circuits at the overlap of the positive and negative busbars.

[0083] In one embodiment, a housing 1500 is also provided below the printed circuit board 1100. The housing 1500 includes a coolant channel 1510 for cooling the heat of the printed circuit board 1100 and the DC link capacitor corresponding to the DC bus unit 1300.

[0084] In this embodiment, the coolant channel is a channel structure used to accommodate the flow of coolant. In practical applications, the printed circuit board generates heat during operation, and the DC link capacitors corresponding to the DC bus unit also generate a large amount of heat. Based on the compact design between the printed circuit board and the DC bus unit in this embodiment, the coolant circulates in the coolant channel, and the heat from both the printed circuit board and the DC link capacitors can be carried away simultaneously through heat conduction.

[0085] Specifically, heat is transferred from the printed circuit board and DC link capacitors to the coolant channel walls in contact with them. Since the coolant is relatively cool, the heat from the channel walls is transferred to the coolant. As the coolant continues to flow, this absorbed heat is carried out of the system and dissipated, thus cooling the bottom of the printed circuit board and the top of the DC link. This prevents overheating from causing performance degradation or even damage to electronic components, ensuring that the electric vehicle can operate stably within a suitable temperature range.

[0086] In one embodiment, the DC bus unit 1300 further includes a second DC bus 1320 disposed on the housing 1500 and located below the first DC bus 1310. The second DC bus 1320 is used to connect to a DC power supply and has a positive interface 1321 for connecting to the DC power supply and a negative interface 1322 for connecting to the DC power supply.

[0087] The DC positive busbar 1311 is connected to the DC positive input terminal through the DC positive interface 1321 of the second DC busbar 132; the DC negative busbar 1312 is connected to the DC negative input terminal through the DC negative interface 1322 of the second DC busbar 1320.

[0088] In this embodiment, the second DC bus can be located directly below the first DC bus, that is, the second DC bus is disposed on the side of the housing, and this side is on the same plane as the first side of the printed circuit board, so as to further optimize the spatial layout and shorten the current path.

[0089] By directly connecting a second DC bus to an external DC power source (such as a battery), electrical energy is introduced into the inverter. Then, the energy is transmitted through a specific path to the first DC bus in the DC link. This layered design of two DC buses utilizes the first DC bus as the core layer for power transmission, employing an alternating positive and negative electrode arrangement to specifically optimize low inductance characteristics under high-frequency switching conditions. The second DC bus serves as the power input layer, providing a standardized DC interface and handling high-current transmission. This layered design allows each bus layer to be optimized independently; for example, the upper layer can focus on high-frequency response, while the lower layer ensures steady-state current carrying capacity, thereby further optimizing performance.

[0090] In one embodiment, the vehicle inverter further includes a low-voltage connector 1160 disposed on the printed circuit board 1100, the low-voltage connector 1160 being connected to the gate drive circuit b, and the low-voltage connector 1160 being configured to receive control commands from an external control board and send drive signals to the gate drive circuit b.

[0091] The external control board can be a vehicle controller (VCU) or a motor controller (MCU), and the control command can be a pulse-width modulation (PWM) control signal.

[0092] In this embodiment, by integrating a low-voltage connector on the printed circuit board to receive PWM control commands from the vehicle control unit (VCU) or motor control unit (MCU) and convert them into drive signals for transmission to the gate drive circuit, this design effectively shortens the signal path and further reduces the interference of parasitic inductance on the drive signal, thereby achieving a more precise control of the switching action of the power devices.

[0093] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0094] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0095] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional units.

[0096] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional modules is merely an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0097] The above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them. Although the embodiments of this application have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

[0098] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0099] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A vehicle inverter, characterized by, include: A printed circuit board, the printed circuit board including power devices and gate drive circuits for driving the power devices to be turned on or off; the power devices include an upper bridge power device and a lower bridge power device; A DC bus unit, the DC bus unit includes a first DC bus soldered on a first side of the printed circuit board, the first DC bus includes a DC positive bus and a DC negative bus, the DC positive bus is connected to the first electrode and the DC positive input terminal of the upper bridge power device respectively, and the DC negative bus is connected to the second electrode and the DC negative input terminal of the lower bridge power device; An AC busbar unit is soldered to the second side of the printed circuit board. It is connected to the second electrode of the upper bridge power device, the first electrode of the lower bridge power device, and the load, respectively, so as to drive the load based on the on or off state of the power device.

2. The vehicle inverter of claim 1, wherein, At least a portion of the area between the DC positive busbar and the DC negative busbar is arranged in an overlapping configuration; the DC busbar unit further includes: An insulating film material is disposed in the overlapping area between the DC positive busbar and the DC negative busbar; The insulating film material is configured to provide electrical insulation for the overlapping portion between the DC positive busbar and the DC negative busbar.

3. The vehicle inverter according to claim 1 or 2, characterized in that, The gate driving circuit is disposed on the upper surface layer of the printed circuit board, and the power device is embedded in the inner layer of the printed circuit board; a shielding layer for shielding electromagnetic interference is included between the upper surface layer and the inner layer. The lower surface layer of the printed circuit board is provided with a thermally conductive layer, and the material of the thermally conductive layer includes a thermally conductive interface material.

4. The vehicle inverter of claim 3, wherein, Also includes: A heat sink is provided, wherein the printed circuit board is mounted on the heat sink via the thermally conductive layer to dissipate heat from the electronic components on the printed circuit board.

5. The vehicle inverter according to claim 1 or 2, characterized in that, Also includes: A housing disposed below the printed circuit board includes a coolant channel configured to cool the printed circuit board and the DC link capacitors corresponding to the DC bus unit.

6. The vehicle inverter of claim 5, wherein, The DC bus unit further includes a second DC bus disposed on the housing and located below the first DC bus. The second DC bus is used to connect to a DC power supply and has a positive interface for connecting to the DC power supply and a negative interface for connecting to the DC power supply. The DC positive busbar is connected to the DC positive input terminal through the DC positive interface of the second DC busbar; the DC negative busbar is connected to the DC negative input terminal through the DC negative interface of the second DC busbar.

7. The vehicle inverter of any one of claims 1-6, wherein, The printed circuit board includes: A first substrate, wherein a first chip packaging unit and a second chip packaging unit are embedded in the first substrate, the first chip packaging unit includes the upper bridge power device, and the second chip packaging unit includes the lower bridge power device; A second substrate disposed on the upper layer of the first substrate, the upper surface of the second substrate including the gate driving circuit, the gate driving circuit including a first gate driving circuit and a second gate driving circuit; A transmission channel penetrating the first substrate and the second substrate, the transmission channel including a first transmission channel and a second transmission channel, the first transmission channel being configured to transmit the drive signal of the first gate drive circuit to the upper bridge power device to drive the upper bridge power device to turn on or off, and the second transmission channel being configured to transmit the drive signal of the second gate drive circuit to the lower bridge power device to drive the lower bridge power device to turn on or off.

8. The vehicle inverter of claim 7, wherein, The first transmission channel is connected to the first control electrode of the upper bridge power device, and the second transmission channel is connected to the second control electrode of the lower bridge power device; wherein... The first control electrode is led out to the upper surface of the second substrate through the first transmission channel, so that the first control electrode is connected to the first gate driving circuit to receive the driving signal transmitted by the first gate driving circuit. The second control electrode is led out to the upper surface of the second substrate through the second transmission channel, so that the second control electrode is connected to the second gate driving circuit to receive the driving signal transmitted by the second gate driving circuit.

9. The vehicle inverter according to claim 7, characterized in that, The transmission channel further includes a third transmission channel connected to the first electrode of the upper bridge power device, a fourth transmission channel connected to the upper end of the first metal support block, a fifth transmission channel connected to the second electrode of the lower bridge power device, and a sixth transmission channel connected to the upper end of the second metal support block; wherein, the first metal support block is a conductive support component configured to be embedded in the first substrate and supporting the upper bridge power device in the first chip packaging unit, and the second metal support block is a conductive support component configured to be embedded in the first substrate and supporting the lower bridge power device in the second chip packaging unit; The first electrode of the upper bridge power device is led out to the surface of the printed circuit board through the second transmission channel, so that the first electrode of the upper bridge power device is connected to the DC positive busbar; the second electrode of the upper bridge power device is led out to the surface of the printed circuit board through the fourth transmission channel, so that the second electrode of the upper bridge power device is connected to the AC busbar unit. The second electrode of the lower bridge power device is led out to the surface of the printed circuit board through the fifth transmission channel, so that the second electrode of the lower bridge power device is connected to the DC negative busbar; the first electrode of the lower bridge power device is led out to the surface of the printed circuit board through the sixth transmission channel, so that the first electrode of the lower bridge power device is connected to the AC busbar unit.

10. The vehicle inverter of claim 7, wherein, The transmission channel is a micropore with a metal coating on the inside, and the number of micropores is determined based on a predefined current carrying requirement.

11. The vehicle inverter according to any one of claims 1-6, characterized in that, Also includes: A low-voltage connector is disposed on the printed circuit board and connected to the gate drive circuit. The low-voltage connector is configured to receive control commands from an external control board and send drive signals to the gate drive circuit.

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