A multi-stage filtering integrated device, electric drive system and vehicle

Abstract

The utility model discloses a kind of multi-stage filtering integrated devices, electric drive system and vehicle, belong to new energy electric car electric drive technical field, multi-stage filtering integrated devices include structural member, multiple magnetic elements, multi-stage capacitor filter unit and copper bar;The copper bar is fixed on structural member, and copper bar end is used for connecting load by lead through magnetic element, other magnetic element is set on copper bar and is connected with structural member;Multi-stage capacitor filter unit is interval arranged along the arrangement direction of copper bar, and capacitor filter unit includes PCB board, and capacitor is set on it, PCB board is across set on the top of copper bar, grounding point of PCB board is embedded with ground terminal, and the pin of capacitor is respectively connected with copper bar and ground terminal of PCB board;The multi-stage filtering integrated device can effectively suppress common mode and differential mode noise of electric drive in new energy electric car, filtering performance meets international standard, and has the characteristics of strong electrical stability and strong structure.

Description

Technical Field

[0001] This utility model relates to the field of electric drive technology for new energy electric vehicles, specifically a multi-level filter integrated device, an electric drive system, and a vehicle. Background Technology

[0002] As a core power component, the electric drive system of new energy electric vehicles not only requires high efficiency and energy saving, but also must have good electromagnetic compatibility (EMC). Electromagnetic interference (EMI) is an issue that cannot be ignored in electric drive systems. It originates from the high-speed switching of power electronic devices, high-frequency currents, and complex wiring structures in the system. The electromagnetic fields generated by these factors can interfere with the vehicle's internal electronic control systems, such as the battery management system (BMS) and motor control unit (MCU), thereby leading to a decline in overall vehicle performance.

[0003] Existing EMI filters employ a discrete layout of capacitors and magnetic components, resulting in complex circuitry, inconsistent grounding paths, and increased parasitic interference. Secondly, the separate arrangement of magnetic components and capacitor assemblies occupies significant space, failing to meet the compact design requirements of automotive electric drive systems. Furthermore, a single filter structure is insufficient for suppressing common-mode and differential-mode noise in high-current scenarios, making it difficult to meet the stringent requirements of international standards (such as GB / T 18655 and ECE R10). Additionally, the filter's PCB board, secured with screws, is prone to loosening due to mechanical vibration or thermal stress, affecting the filter's long-term stability and lifespan. Therefore, existing EMI filters are ill-suited to the filtering needs of current high-current automotive electric drive applications. Utility Model Content

[0004] To address the problems existing in the prior art, this utility model provides a multi-level filter integrated device, an electric drive system, and a vehicle, which can effectively suppress common-mode and differential-mode noise, reduce electromagnetic interference, and improve electromagnetic compatibility.

[0005] This utility model is achieved through the following technical solution:

[0006] A multi-stage filter integrated device includes structural components, multiple magnetic elements, a multi-stage capacitor filter unit, and a copper busbar;

[0007] The copper busbar is fixed to the structural component. At least one end of the copper busbar is provided with magnetic elements at intervals. The end of the copper busbar is connected to the load by passing through the magnetic elements with a lead wire. Other magnetic elements are sleeved on the copper busbar and connected to the structural component.

[0008] Multi-stage capacitor filter units are spaced apart along the copper busbar arrangement direction. Each capacitor filter unit includes a PCB board and capacitors mounted on it. The PCB board spans the top of the copper busbar. The grounding point of the PCB board has a grounding terminal embedded in it. The filter circuit of the PCB board has multiple layers of copper plating, which are connected to the grounding terminal. The capacitor pins are connected to the grounding terminal of the copper busbar and / or the PCB board, respectively.

[0009] Preferably, the magnetic element includes a first magnetic element and a second magnetic element;

[0010] The mechanism is provided with a receiving groove, and a magnetic element is disposed in the receiving groove. The first magnetic element is disposed at one end of the copper busbar, and the other end of the copper busbar passes through the second magnetic element.

[0011] Preferably, the multi-stage capacitor filter unit includes a first-stage capacitor filter unit, a second-stage capacitor filter unit, and a third-stage capacitor filter unit arranged sequentially. A second magnetic ring is located between the second-stage capacitor filter unit and the third-stage capacitor filter unit, and the second magnetic ring is sleeved on the copper busbar. The third-stage capacitor filter unit is located at the end of the structural component, and the first-stage capacitor filter unit is located at the end of the copper busbar near the first magnetic element.

[0012] Preferably, the copper busbar includes a positive copper busbar and a negative copper busbar, which are fixed to the structural component at equal intervals, and the positive and negative copper busbars have an L-shaped structure.

[0013] Preferably, the grounding terminal is a ring-shaped metal part, and the grounding point of the PCB board is provided with a fixing hole. The ring-shaped metal part is installed in the fixing hole, and the ratio of the height to the diameter of the ring-shaped metal part is less than 5:1.

[0014] Preferably, each stage of the capacitor filtering unit includes a PCB board, a common-mode capacitor and / or a differential-mode capacitor, with two common-mode capacitors respectively disposed at both ends of the PCB board, and grounding points disposed at both ends of the PCB board, with grounding terminals embedded in the grounding points.

[0015] The PCB board is set on top of the copper busbar, and the copper busbar is welded to the welding pillar of the PCB board. Both ends of the PCB board extend to both sides of the copper busbar. Inserts are embedded in the connection nodes set on the structural components, and the PCB board is connected to the inserts of the connection nodes by screws.

[0016] Preferably, the PCB board and structural components are filled with silicone rubber.

[0017] Preferably, one pin of the common-mode capacitor is soldered to the grounding terminal on the PCB board, and then connected to the positive copper busbar and the negative copper busbar respectively. The two pins of the differential-mode capacitor are soldered to the positive copper busbar and the negative copper busbar respectively.

[0018] An electric drive system includes a power supply and an electric drive device, wherein the multi-stage filter integrated device of the power supply is connected to the electric drive device.

[0019] A new energy vehicle includes the aforementioned electric drive system.

[0020] Compared with the prior art, the present invention has the following beneficial technical effects:

[0021] This application discloses an integrated high-current multi-stage filter device for vehicles, employing an injection-molded structure. Internally, it integrates copper busbar housings, magnetic component slots, and PCB mounting slots, achieving a high degree of integration between the magnetic components, copper busbars, and multi-stage capacitor filter units, improving space utilization by over 30%. Two stages of magnetic components are connected via positive and negative copper busbars and welded to the multi-stage capacitor filter units to form a three-stage LC filter topology network. Common-mode and differential-mode noise attenuation are both ≥40dB at 1MHz, meeting international standards. A multi-layer copper-plated PCB design, combined with multi-point welding of ring-shaped metal grounding terminals, ensures a ground impedance of <1Ω, enabling efficient multi-channel discharge of common-mode current. This device combines integration, miniaturization, and high reliability, making it suitable for high-current scenarios in electric drive systems of new energy vehicles.

[0022] Furthermore, the magnetic components are fixed in the structural component grooves using flame-retardant polyurethane potting compound, and the connection between the PCB board and the structural component is filled with silicone rubber, which effectively avoids loosening caused by mechanical vibration or thermal stress and improves long-term stability. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of the multi-stage filter integrated device of this utility model.

[0025] Figure 2 This is a schematic diagram showing the distribution of the copper busbar and magnetic components of this utility model.

[0026] Figure 3 This is a schematic diagram of the multi-stage filter circuit of this utility model.

[0027] Figure 4 This is a schematic diagram of the first-stage capacitor filter unit of this utility model.

[0028] Figure 5 This is a schematic diagram of the second-stage capacitor filter unit of this utility model.

[0029] Figure 6 This is a schematic diagram of the third-stage capacitor filter unit of this utility model.

[0030] Figure 7 This is a circuit topology diagram of the present invention.

[0031] Figure 8 This is an exploded view of the structure of this utility model.

[0032] Figure 9 This is an experimental diagram of the differential mode loss of the multi-stage filter integrated device of this utility model.

[0033] Figure 10 This is an experimental diagram showing the common-mode loss of the multi-stage filter integrated device of this utility model.

[0034] In the diagram: 1. Magnetic component; 2. Negative copper busbar; 3. Positive copper busbar; 4. First-stage capacitor filter unit; 5. Second-stage capacitor filter unit; 6. Magnetic component; 7. Grounding terminal; 8. Third-stage capacitor filter unit; 9. Structural component; 10. Common-mode capacitor; 11. Differential-mode capacitor. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0037] See Figure 1 A multi-stage filter integrated device includes structural components, multiple magnetic elements, a multi-stage capacitor filter unit, and a copper busbar. The number of multiple magnetic elements and the multi-stage capacitor filter unit is set according to the switching frequency of the load.

[0038] The copper busbar is fixed to the structural component. At least one end of the copper busbar is provided with magnetic elements at intervals. The end of the copper busbar passes through the magnetic elements with leads to connect the load. Other magnetic elements are sleeved on the copper busbar and connected to the structural component.

[0039] Multi-stage capacitor filter units are spaced apart along the copper busbar arrangement direction. Each capacitor filter unit includes a PCB board and capacitors mounted on it. The PCB board spans the top of the copper busbar. The grounding point of the PCB board is embedded with a grounding terminal 7. The filter circuit of the PCB board is provided with multiple layers of copper wires. The multiple layers of copper are connected to the grounding terminal 7. The leads of the capacitors are connected to the grounding terminal 7 of the copper busbar and the PCB board, respectively.

[0040] Optionally, the magnetic element includes a first magnetic element 1 and a second magnetic element 6.

[0041] The first magnetic element 1 is a circular magnetic ring. The end of the structural component is provided with a receiving groove for mounting the circular magnetic ring. The magnetic ring is encapsulated in the receiving groove and is spaced apart from the end of the copper busbar. The end of the copper busbar is connected to the load power device through the circular magnetic ring via a lead wire. This is equivalent to the end of the copper busbar passing through the magnetic element, which can effectively shorten the length of the copper busbar and prevent the end of the copper busbar from extending to the outside of the structural component, thereby reducing the volume of the entire integrated device.

[0042] Optionally, the magnetic element is fixed in the receiving groove of the structural component by potting adhesive.

[0043] Understandably, the other end of the copper busbar can also adopt the same design, with another magnetic element placed at the other end of the copper busbar, and the copper busbar fixed as a whole on the structural component. That is, the first magnetic element 1 and the second magnetic element 6 are located at the two ends of the copper busbar respectively, and the two ends of the copper busbar are connected to the positive and negative poles of the load power device through the corresponding magnetic elements via leads, further reducing the size of the integrated device.

[0044] Furthermore, the magnetic element can be placed in the middle of the structure, allowing the end of the copper busbar to pass directly through the magnetic element and extend into the structure, where it can be connected to the load power device via leads.

[0045] Optionally, the copper busbar includes a positive copper busbar 3 and a negative copper busbar 2, which are equally spaced and welded to the structural component. The positive copper busbar 3 and the negative copper busbar 2 are L-shaped structures. This L-shaped design can effectively shorten the length of the copper busbar and utilize the width space of the structural component to reduce the volume of the structural component.

[0046] Optionally, the grounding terminal is a ring-shaped metal part. The grounding point of the PCB board is provided with a fixing hole, and the ring-shaped metal part is installed in the fixing hole. The length-to-width ratio of the grounding terminal is less than 5:1, that is, the height-to-diameter ratio of the ring-shaped metal part is less than 5:1. The material of the ring-shaped metal part is preferably copper, and the height-to-diameter ratio is 7:5.

[0047] See Figure 3The multi-stage capacitor filter unit includes a first-stage capacitor filter unit 4, a second-stage capacitor filter unit 5, and a third-stage capacitor filter unit 8.

[0048] Starting from the end of the copper busbar near the first magnetic element, the first-stage capacitor filter unit 4, the second-stage capacitor filter unit 5, and the third-stage capacitor filter unit 8 are arranged in sequence. The second magnetic ring is located between the second-stage capacitor filter unit 5 and the third-stage capacitor filter unit 8, and the second magnetic ring is sleeved on the copper busbar. The third-stage capacitor filter unit 8 is located at the end of the structural component.

[0049] See Figure 4 The first-stage capacitor filter unit 4 includes a PCB board and two common-mode capacitors 10. The two common-mode capacitors 10 are respectively set at both ends of the PCB board. Grounding points are set at both ends of the PCB board, and grounding terminals are embedded in the grounding points.

[0050] The PCB board is positioned at the top of the copper busbar in the middle. The copper busbar is welded to the welding posts of the PCB board. Both ends of the PCB board extend towards the sides of the copper busbar. One lead of the common-mode capacitor is welded to the grounding terminal 7 of the grounding point on the PCB board, and then connected to the positive copper busbar 3 and the negative copper busbar 2 respectively. Inserts are embedded in the connection nodes of the structural component. The PCB board is connected to the inserts of the connection nodes by screws. By embedding inserts in the structural component, the problem of cracking of the structural component caused by screw installation is solved, avoiding the direct fixing of screws to the structural component. Preferably, the insert is a copper nut.

[0051] The filter circuit of the PCB board is treated with multi-layer copper pouring, forming multiple layers of copper lines in the filter circuit of the PCB board. The multiple layers of copper lines are connected to the terminals of the grounding point. When all grounding points are connected, the impedance to ground is less than 1Ω.

[0052] See Figure 5 The second-stage capacitor filter unit includes a PCB board, two common-mode capacitors 10 and one differential-mode capacitor 11. The two common-mode capacitors are respectively set at both ends of the PCB board. Grounding points are set at both ends of the PCB board, and grounding terminals 7 are embedded in the grounding points. The differential-mode capacitor is connected to the PCB board and is located between the two common-mode capacitors.

[0053] One pin of the common-mode capacitor is soldered to the grounding terminal 7 on the PCB board, and then connected to the positive copper busbar 3 and the negative copper busbar 2 respectively. The two pins of the differential-mode capacitor 11 are soldered to the positive copper busbar and the negative copper busbar respectively. The filter circuit of the PCB board is subjected to multi-layer copper pouring treatment, forming multi-layer copper lines in the filter circuit of the PCB board. The multi-layer copper lines are connected to the grounding terminal. When all grounding points are connected, the impedance to ground is less than 1Ω.

[0054] See Figure 6The third-stage capacitor filter unit includes a PCB board, two common-mode capacitors 10 and one differential-mode capacitor 11. The common-mode capacitors are respectively set at both ends of the PCB board. Grounding points are set at both ends of the PCB board, and grounding terminals 7 are embedded in the grounding points. The differential-mode capacitor is connected to the PCB board and is located between the two common-mode capacitors, and is located on the other side of the PCB board.

[0055] One pin of the common-mode capacitor is soldered to the grounding terminal 7 on the PCB board, and then connected to the positive copper busbar 3 and the negative copper busbar 2 respectively. The two pins of the differential-mode capacitor 11 are soldered to the positive copper busbar and the negative copper busbar respectively. The filter circuit of the PCB board is subjected to multi-layer copper pouring, that is, a copper layer is formed on the filter circuit. The multi-layer copper wires are connected to the grounding terminal. When all grounding points are connected, the impedance to ground is less than 1Ω.

[0056] Optionally, silicone rubber is filled between the PCB board and the structural component of the multi-stage capacitor filter unit to improve the connection stability between the multi-stage capacitor filter unit and the structural component 9. After the multi-stage capacitor filter unit is installed, silicone rubber is injected into the gap between the PCB board and the structural component to reinforce the multi-stage capacitor filter unit and the structural component.

[0057] Example 1

[0058] The circuit schematics of the capacitor filter units at each stage in the multi-stage filter integrated device of this application are as follows: Figure 7 As shown, the main topology is an LC structure. When current flows through the positive and negative lines, the interaction between the inductor and capacitor achieves the purpose of suppressing common-mode noise.

[0059] In the first-stage magnetic filter circuit, the inductance of L1 ranges from 70μH to 150μH.

[0060] In the first-stage capacitor filter unit, the capacitance value of the common-mode capacitor 10 ranges from 0.22μF to 4.7μF.

[0061] In the second-stage capacitor filter unit, the capacitance value of the common-mode capacitor 10 ranges from 0.01μF to 2μF, and the capacitance value of the differential-mode capacitor Cx1 ranges from 0.01μF to 0.1μF.

[0062] In the second-stage magnetic filter circuit, the inductance of L2 ranges from 5μH to 20μH.

[0063] In the third-stage capacitor filter unit, the capacitance value of the common-mode capacitor 10 ranges from 0.1μF to 4.7μF, and the capacitance value of the differential-mode capacitor 11 ranges from 0.01μF to 0.22μF.

[0064] In this example, the filter current passes through each stage of capacitor filtering unit, and then the common-mode current is quickly discharged through the multi-layer copper and metal grounding terminals.

[0065] The exploded view of the multi-stage filter integrated device in this embodiment is shown below. Figure 8 As shown.

[0066] like Figure 8 As shown, the positive and negative copper busbars are welded and fixed in the receiving groove of structural component 1, and each capacitor filter unit is welded and fixed in the receiving groove of structural component 1; each magnetic component is fixed in the receiving groove of structural component 1 by potting glue. The welding process adopts reflow soldering.

[0067] The positive and negative copper busbars are designed in a parallel symmetrical structure, which can reduce the processing difficulty of the copper busbars and improve their versatility; structural component 1 is an injection-molded shell, which can reduce the manufacturing cost during the design process; the inserts are standard universal parts, which can save the filter manufacturing and assembly cycle and improve the filter production efficiency.

[0068] The magnetic components are secured using flame-retardant polyurethane potting compound. After the multi-stage capacitor filter unit is assembled, silicone rubber is used to fix the bolts and inserts on the PCB board. Existing EMI filters are mostly installed using screws to secure the circuit board components to the structural parts. However, under normal use, these screws are prone to loosening under various stresses, significantly reducing the filter's lifespan and impairing its function, thus affecting its normal operation. In this application, the bolts and inserts on the PCB board avoid stress concentration at the structural connection points, thereby improving the filter's lifespan.

[0069] See Figure 9 and 10 The vehicle-mounted high-current multi-stage filter integrated device of the embodiment was tested using a network analyzer. Figure 9 This is a differential mode loss diagram. Figure 10 The common-mode loss curves all show attenuation to below 40dB at around 1MHz, meeting the Chinese standard GB / T 18655 and the European standard ECE R10.

[0070] The positive and negative copper busbars of this multi-stage filter integrated device run in parallel through the first and second stage magnetic components and are fixed to the structural components. The capacitor filter circuit consists of a PCB board and an adjustable capacitor, which are soldered to the copper busbars to form a multi-stage LC filter topology. By optimizing the structural component design, the magnetic components and circuit components are integrated into the receiving slot, combined with potting compound fixation and multi-layer copper grounding technology, achieving miniaturization, lightweighting, and high space utilization. This filter can effectively suppress common-mode and differential-mode noise in the electric drive of new energy electric vehicles, and its filtering performance meets international standards. It also features strong electrical stability and structural strength.

[0071] Example 2

[0072] An electric drive system includes a power supply, an electric drive device, and the aforementioned multi-stage filter integrated device.

[0073] Multi-stage filter integrated devices connect the power supply and electric drive equipment, and transmit the high-voltage DC high-current signal formed after filtering out EMI from the power supply signal to the electric drive equipment.

[0074] Example 3

[0075] A new energy vehicle includes the electric drive system described in Example 2.

[0076] This application discloses a multi-stage filter integrated device, which features high integration, simple structure, miniaturization, and lightweight design. By using multiple stages of filters, it can effectively suppress common-mode noise and differential-mode noise in new energy electric drives, meeting the requirements of international and national standards, and ensuring that other functions of new energy electric vehicles are not affected.

[0077] The above content is only for illustrating the technical concept of this utility model and should not be construed as limiting the scope of protection of this utility model. Any modifications made to the technical solution based on the technical concept proposed in this utility model shall fall within the scope of protection of the claims of this utility model.

Claims

1. A multi-stage filter integrated device, characterized in that, Includes structural components, multiple magnetic elements, multi-stage capacitor filter units, and copper busbars; The copper busbar is fixed to the structural component. At least one end of the copper busbar is provided with magnetic elements at intervals. The end of the copper busbar is connected to the load by passing through the magnetic elements with a lead wire. Other magnetic elements are sleeved on the copper busbar and connected to the structural component. Multi-stage capacitor filter units are spaced apart along the copper busbar arrangement direction. Each capacitor filter unit includes a PCB board and capacitors mounted on it. The PCB board spans the top of the copper busbar. The grounding point of the PCB board has a grounding terminal embedded in it. The filter circuit of the PCB board has multiple layers of copper plating, which are connected to the grounding terminal. The capacitor pins are connected to the grounding terminal of the copper busbar and / or the PCB board, respectively.

2. The multi-stage filter integrated device according to claim 1, characterized in that, The magnetic element includes a first magnetic element and a second magnetic element; The structural component is provided with a receiving groove, and a magnetic element is placed in the receiving groove. The first magnetic element is placed at one end of the copper busbar, and the other end of the copper busbar passes through the second magnetic element.

3. The multi-stage filter integrated device according to claim 2, characterized in that, The multi-stage capacitor filter unit includes a first-stage capacitor filter unit, a second-stage capacitor filter unit, and a third-stage capacitor filter unit arranged sequentially. A second magnetic ring is located between the second-stage capacitor filter unit and the third-stage capacitor filter unit, and the second magnetic ring is sleeved on the copper busbar. The third-stage capacitor filter unit is located at the end of the structural component, and the first-stage capacitor filter unit is located at the end of the copper busbar near the first magnetic element.

4. The multi-stage filter integrated device according to claim 1, characterized in that, The copper busbar includes a positive copper busbar and a negative copper busbar, which are fixed to the structural component at equal intervals. The positive and negative copper busbars have an L-shaped structure.

5. The multi-stage filter integrated device according to claim 1, characterized in that, The grounding terminal is a ring-shaped metal part. The grounding point of the PCB board is provided with a fixing hole, and the ring-shaped metal part is installed in the fixing hole. The ratio of the height to the diameter of the ring-shaped metal part is less than 5:

1.

6. The multi-stage filter integrated device according to claim 1, characterized in that, Each capacitor filter unit includes a PCB board, common-mode capacitors and / or differential-mode capacitors. Two common-mode capacitors are respectively set at both ends of the PCB board. Grounding points are set at both ends of the PCB board, and grounding terminals are embedded in the grounding points. The PCB board is set on top of the copper busbar, and the copper busbar is welded to the welding pillar of the PCB board. Both ends of the PCB board extend to both sides of the copper busbar. Inserts are embedded in the connection nodes set on the structural components, and the PCB board is connected to the inserts of the connection nodes by screws.

7. A multi-stage filter integrated device according to claim 6, characterized in that, The PCB board and structural components are filled with silicone rubber.

8. A multi-stage filter integrated device according to claim 6, characterized in that, One pin of the common-mode capacitor is soldered to the ground terminal on the PCB board, and then connected to the positive and negative copper busbars respectively. The two pins of the differential-mode capacitor are soldered to the positive and negative copper busbars respectively.

9. An electric drive system, characterized in that, It includes a power supply and an electric drive device, wherein the power supply is connected to the electric drive device through a multi-stage filtering integrated device as described in any one of claims 1-8.

10. A vehicle, characterized in that, Includes the electric drive system as described in claim 9.

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