A capacitor module with integrated EMC boost, fuse and four-level EMC filtering functions

Abstract

The present invention discloses a capacitor module integrating EMC boosting, fuses, and four-stage EMC filtering functions, relating to the technical field of capacitors. The module, which integrates EMC boosting, fuses, and four-stage EMC filtering functions, is used in electric vehicle motor control circuits. The module comprises a frame body within which two capacitor cores are arranged side by side: one is a filter capacitor C1, and the other is a DC support film capacitor C2. The module also integrates an EMC boosting module, a fuse module, and a four-stage EMC filtering module. Through high integration, four-stage EMC filtering, anti-circulation circuitry, dual fuse protection, optimized heat dissipation, and ease of installation and maintenance, the present invention significantly improves system performance, reliability, and stability, while reducing overall costs.

Description

Technical Field

[0001] The present invention belongs to the technical field of capacitors, and in particular relates to a capacitor module integrating EMC boosting, fuse and four-stage EMC filtering functions. Background Art

[0002] DC support film capacitors have two functions in the motor control circuit of electric vehicles. First, the capacitor provides ripple current when the upper bridge arm of the inverter is turned off and the lower bridge arm is turned on, avoiding adverse effects such as motor torque pulsation and current sampling distortion when the voltage fluctuation is too large; second, the capacitor provides a loop for the high-frequency current generated by the system, reducing the loop impedance, switching loss and voltage spikes.

[0003] Traditional capacitor modules offer a single function, typically requiring external boost circuits, fuses, and multi-stage filtering modules. This results in a bulky system, complex connections, and low reliability. Existing EMC filtering often employs a two- or three-stage structure, which has limited ability to suppress high-frequency interference. Fuses and boost modules are designed independently, resulting in slow fault response. Furthermore, existing modules suffer from insufficient heat dissipation, making them difficult to adapt to high-load or high-temperature environments. Therefore, a highly integrated, performance-optimized, and highly reliable capacitor module is urgently needed. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a capacitor module with integrated EMC boost, fuse and four-level EMC filtering functions that can overcome the above problems or at least partially solve the above problems.

[0005] To solve the above technical problems, the basic concept of the technical solution adopted by the present invention is: a capacitor module integrating EMC boost, fuse and four-stage EMC filtering functions, for use in electric vehicle motor control circuits. The capacitor module includes a frame body, in which two capacitor cores are arranged in parallel, one of which is a filter capacitor C1 and the other is a DC support film capacitor C2. The frame body also integrates: an EMC boost module for boosting the input power voltage to a preset value; a fuse module including a fast-blow fuse K1 and a DC-DC fuse K2; a four-stage EMC filter module composed of first to fourth-stage EMC filter circuits connected in sequence; an anti-circuit current circuit is provided between the second-stage EMC filter circuit and the third-stage EMC filter circuit, and the anti-circuit current circuit is composed of a filter capacitor C1, a filter inductor L2 and a fast-blow fuse K1; a positive and negative copper busbar and a grounding copper busbar are provided in the frame body, wherein the positive and negative copper busbars are provided with mounting portions, and both ends of the grounding copper busbar extend to the outside of the frame.

[0006] Preferably, the filter capacitor C1 and the DC support film capacitor C2 are arranged in parallel, corresponding to the four-stage filter circuit and the anti-circulation circuit in the four-stage EMC filter module respectively.

[0007] Preferably, the four-stage EMC filter module specifically includes: a first-stage EMC filter circuit: including a differential mode capacitor CX1, a common mode capacitor CY1, and a common mode capacitor CY2; a second-stage EMC filter circuit: including a differential mode capacitor CX2, a common mode capacitor CY3, a common mode capacitor CY4, and a differential mode inductor L1; a third-stage EMC filter circuit: including a common mode capacitor CY5 and a common mode capacitor CY6; a fourth-stage EMC filter circuit: including a common mode capacitor CY7, a common mode capacitor CY8, a common mode capacitor CY9, a common mode capacitor CY10, a common mode capacitor CY11, a common mode capacitor CY12, and the DC support film capacitor C2.

[0008] Preferably, the fast-blow fuse K1 is set in the anti-circulation circuit, and the DC-DC fuse K2 is set at the high-voltage input end and works in conjunction with the contactor and the pre-charging circuit; the bottom and side of the frame body are provided with multiple EMC capacitor mounting positions, and the interior is filled with an epoxy resin or polyurethane sealing filling layer.

[0009] Preferably, the filter inductor L2 is composed of a magnetic ring arranged in the frame body, and the positive and negative copper bars pass through the magnetic ring to form an inductor structure; the grounding copper bar forms a multi-point grounding structure through the extension part of the frame body.

[0010] Preferably, an open installation cavity is provided on the side of the frame body, and the common-mode capacitors CY1, CY2, CY3 and CY4 are fixed in the open cavity through a potting process and directly welded to the extended end of the grounding copper busbar.

[0011] Preferably, the mounting portion of the positive and negative copper busbars comprises a standardized interface, an insulating isolation groove is provided at the interface, and the positive and negative pins of the DC support film capacitor C2 are connected to the copper busbar interface by laser welding.

[0012] Preferably, the magnetic ring is made of nanocrystalline alloy, and the gap between its inner diameter and the cross-section of the positive and negative copper bars is 0.5-1 mm. The outer surface of the magnetic ring is covered with a silicone buffer layer and is fixed to the inner wall of the frame body by a snap-fit ​​structure.

[0013] After adopting the above technical solution, the present invention has the following beneficial effects compared with the existing technology: the present invention significantly improves the performance, reliability and stability of the system and reduces the overall cost through designs such as high integration, four-level EMC filtering, anti-circulation circuit, double fuse protection, optimized heat dissipation performance, and easy installation and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In the attached figure:

[0015] Figure 1This is a schematic diagram of the structure of a capacitor module that integrates EMC boost, fuse and four-level EMC filtering functions proposed by the present invention. Figure 1 ;

[0016] Figure 2 This is a schematic diagram of the structure of a capacitor module that integrates EMC boost, fuse and four-level EMC filtering functions proposed by the present invention. Figure 2 ;

[0017] Figure 3 This is a circuit diagram of a capacitor module proposed by the present invention that integrates EMC boost, fuse and four-stage EMC filtering functions.

[0018] In the figure: 1. Frame body; 2. Mounting part; 3. Positive and negative copper busbars; 4. Inductor; 5. Sealing filling layer; 6. Grounding copper busbar; 7. Capacitor core; 8. Magnetic ring; 9. EMC capacitor. DETAILED DESCRIPTION

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments so that those skilled in the art can implement the invention with reference to the description.

[0020] It should be understood that terms such as “having”, “including” and “comprising” used herein do not preclude the existence or addition of one or more other elements or combinations thereof.

[0021] In the description of the present invention, the terms "horizontal", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0022] Example 1: Reference Figure 1-Figure 3, a capacitor module integrating EMC boost, fuse and four-level EMC filtering functions, used in electric vehicle motor control circuits, the capacitor module includes a frame body, two capacitor cores are arranged in parallel in the frame body, one of which is a filter capacitor C1, and the other is a DC support film capacitor C2, and is integrated with: an EMC boost module for increasing the input power voltage to a preset value; a fuse module, including a fast-blow fuse K1 and a DC-DC fuse K2; a four-level EMC filter module, consisting of a first to a fourth-level EMC filter circuit connected in sequence; an anti-circulation circuit is provided between the second-level EMC filter circuit and the third-level EMC filter circuit, and the anti-circulation circuit consists of a filter capacitor C1, a filter inductor L2 and a fast-blow fuse K1; a positive and negative copper busbar and a grounding copper busbar are provided in the frame body, wherein the positive and negative copper busbars are provided with Installation part, both ends of the grounding copper busbar extend to the outside of the frame; the filter capacitor C1 and the DC support film capacitor C2 are arranged in parallel, corresponding to the four-stage filter circuit and the anti-circulation circuit in the four-stage EMC filter module respectively; the four-stage EMC filter module specifically includes: first-stage EMC filter circuit: including differential mode capacitor CX1, common mode capacitor CY1, common mode capacitor CY2; second-stage EMC filter circuit: including differential mode capacitor CX2, common mode capacitor CY3, common mode capacitor CY4 and differential mode inductor L1; third-stage EMC filter circuit: including common mode capacitor CY5, common mode capacitor CY6; fourth-stage EMC filter circuit: including common mode capacitor CY7, common mode capacitor CY8, common mode capacitor CY9, common mode capacitor CY10, common mode capacitor CY11, common mode capacitor CY12 and DC support film capacitor C2.

[0023] In the present invention, the EMC boost module is composed of a boost transformer and a switching tube, and is used to increase the voltage of the input power supply to a preset value; the fuses K1 and K2 are fusible wires with a rated current of 75A to 135A, and are used to melt and cut off the circuit when an overcurrent or short circuit fault occurs in the circuit; the four-stage EMC filter module includes four filter units, namely a first-stage EMC filter circuit, a second-stage EMC filter circuit, a third-stage EMC filter circuit, and a fourth-stage EMC filter circuit, which are connected in a stage-by-stage manner;

[0024] Specifically, the first-stage filtering unit (first-stage EMC filtering circuit) consists of a differential-mode capacitor CX1, a common-mode capacitor CY1, and a common-mode capacitor CY2; the capacitance of the differential-mode capacitor CX1 is 1nF to 47nF, and the withstand voltage is 275VAC to 305VAC; the capacitance of the common-mode capacitor CY1 and the common-mode capacitor CY2 are 33nF to 68nF, and the withstand voltage is 275VAC to 305VAC; the inductance of the differential-mode inductor L1 is 30uH to 75uH @ 10KHz and 15uH to 45uH @ 100KHz. One end of the differential-mode capacitor CX1 is connected to one end of the common-mode capacitor CY1, the other end of the common-mode capacitor CY1 is connected to one end of the differential-mode inductor L1, the other end of the differential-mode inductor L1 is connected to one end of the common-mode capacitor CY2, and the other end of the common-mode capacitor CY2 is connected to the other end of the differential-mode capacitor CX1, forming an LC filter network. The first-level EMC filter circuit is located at the front end of the power input to filter out most of the conducted interference (common-mode interference and differential-mode interference) on the power line. The large capacitor bypasses low-frequency differential-mode interference, and the inductor suppresses high-frequency interference from entering the subsequent circuit.

[0025] The second-stage filter unit (secondary EMC filter circuit) consists of a differential-mode capacitor CX1, a common-mode capacitor CY3, a common-mode capacitor CY4, and a differential-mode inductor L1. The capacitance of the common-mode capacitors CY3 and CY4 is 68nF to 150nF, and the withstand voltage is 275VAC to 305VAC. The inductance of the differential-mode inductor L1 is 30uH to 75uH @ 10KHz and 15uH to 45uH @ 100KHz. One end of the common-mode capacitor CY3 is connected to one end of the differential-mode inductor L1, and the other end of the differential-mode inductor L1 is connected to one end of the common-mode capacitor CY4. The other end of the common-mode capacitor CY4 is connected to the other end of the common-mode capacitor CY3, forming a π-type filter network. The secondary EMC filter circuit further filters out residual interference based on the primary filter, especially better suppressing interference in the high-frequency band, reducing interference entering subsequent circuits.

[0026] The third-stage filter unit (three-stage EMC filter circuit) is located after the anti-circuit current circuit and consists of common-mode capacitors CY5 and CY6. Common-mode capacitors CY5 and CY6 have capacitances of 1nF to 33nF and withstand voltages of 275VAC to 305VAC. One end of common-mode capacitor CY5 is connected to filter capacitor C1, the other end of which is connected to one end of common-mode capacitor CY6, and the other end of common-mode capacitor CY6 is connected to the other end of filter capacitor C1, forming a π-type filter network. The three-stage EMC filter circuit is located near the input ports of sensitive circuits and uses sophisticated components to filter out subtle interference left over from the first two stages, protecting sensitive circuits from electromagnetic interference.

[0027] The fourth-stage filter unit (fourth-stage EMC filter circuit) consists of common-mode capacitor CY7, common-mode capacitor CY8, common-mode capacitor CY9, common-mode capacitor CY10, common-mode capacitor CY11, common-mode capacitor CY12 and DC support film capacitor C2; the DC support film capacitor C2 has a capacitance of 250μF to 650μF and a withstand voltage of 400VDC to 900VDC; the common-mode capacitor CY7, common-mode capacitor CY8, common-mode capacitor CY9, common-mode capacitor CY10, common-mode capacitor CY11, and common-mode capacitor CY12 have a capacitance of 1nF to 33nF and a withstand voltage of 275VAC to 305VAC. One end of the DC support film capacitor C2 is connected to one end of the common-mode capacitor CY7, the other end of the common-mode capacitor CY7 is connected to one end of the common-mode capacitor CY8, the other end of the common-mode capacitor CY8 is connected to one end of the common-mode capacitor CY9, the other end of the common-mode capacitor CY9 is connected to one end of the common-mode capacitor CY10, the other end of the common-mode capacitor CY10 is connected to one end of the common-mode capacitor CY11, the other end of the common-mode capacitor CY11 is connected to one end of the common-mode capacitor CY12, and the other end of the common-mode capacitor CY12 is connected to the other end of the DC support film capacitor C2, forming a complex π-type filtering network; the four-stage EMC filtering circuit performs final fine processing on the signal, further suppressing specific frequency interference or common-mode interference to ensure that the output signal meets electromagnetic compatibility requirements;

[0028] Furthermore, the anti-circulation circuit is composed of filter capacitor C1, filter inductor L2 and fast-blow fuse K1. Compared with the traditional anti-circulation circuit, the traditional anti-circulation circuit is generally implemented through two solutions: one is a hardware solution: using a current-sharing inductor, current detection resistor or Hall sensor in conjunction with a control algorithm; the other is a software solution: through PWM modulation optimization. The present invention, composed of filter inductor and filter capacitor, has the following advantages:

[0029] (1) Detect the current unevenness problem caused by IGBT parameter differences in multiple parallel circuits, balance the current distribution through LC peak shaving and valley filling, adjust the current of each branch, and avoid device overstress caused by circulating current.

[0030] (2) Reduce IGBT switching losses. When the upper and lower bridge arms of the inverter are switched, LC filters out the peak voltage and suppresses the instantaneous circulating current caused by dead time or asynchronous driving signal.

[0031] Among them, the capacitance of the filter capacitor C1 is 20μF~50μF, the withstand voltage is 400VDC~900VDC, and under the current condition of 80 amperes (A), the inductance of the filter inductor L2 is 2 microhenry.

[0032] To prevent excessive current in some modules due to circulating current, the fast-blow fuse K1 can respond in milliseconds, protecting the IGBT power device from overcurrent damage, reducing the risk of thermal imbalance, and extending the service life of the controller.

[0033] Example 2: Reference Figure 1-Figure 3 , which is basically the same as Example 1, and furthermore: a fast-blow fuse K1 is set in the anti-circulation circuit, and a DC-DC fuse K2 is set at the high-voltage input end and works in conjunction with the contactor and the pre-charging circuit.

[0034] Furthermore, the fast-blow fuse K1 and the DC-DC fuse K2 are used to blow when an overcurrent or short-circuit fault occurs in the circuit, thereby disconnecting the circuit and protecting the equipment from damage. In this embodiment, both the fast-blow fuse K1 and the DC-DC fuse K2 are fusible wires, and their rated current values ​​are selected based on the design requirements of the circuit. One end of the DC-DC fuse K2 is connected to the output end of the four-stage EMC filter circuit, and the other end is connected to a load such as an air conditioner. This ensures that when an overcurrent or short-circuit fault occurs in the load, the DC-DC fuse K2 can quickly blow, disconnecting the circuit and protecting the safety of the equipment and load. Furthermore, the fast-blow fuse K1 and the DC-DC fuse K2 are arranged between the secondary filter and the circulating circuit. When an overcurrent or short-circuit fault occurs in the circuit, they can quickly blow, disconnecting the circuit, and protecting subsequent circuits and equipment from damage. This arrangement can also prevent the fault from expanding and improve the overall stability and reliability of the circuit.

[0035] Furthermore, the fast-blow fuse K1 is set between the secondary filter and the anti-circulation circuit, which has the following advantages:

[0036] (1) Provide double protection: The secondary filter circuit is mainly responsible for further filtering out the medium and high frequency noise on the power line. If a fuse K1 is set between it and the anti-circulation circuit, it can not only protect the secondary filter circuit itself from overcurrent or short circuit faults, but also protect the anti-circulation circuit and its subsequent circuits (such as the tertiary filter, DC support capacitor, etc.) from faults, forming a double insurance.

[0037] (2) Fault isolation and location: When a circuit fault causes overcurrent or short circuit, fuse K1 blows, isolating the fault area before the secondary filter circuit or after the anti-circulation circuit. This setting helps to quickly locate the fault range, narrow the investigation area, and improve maintenance efficiency.

[0038] (3) Preventing fault expansion: The function of the anti-circulation circuit is to prevent current circulation and protect the safety of circuits and equipment. If an overcurrent or short circuit fault occurs before the anti-circulation circuit and there is no fuse protection, the fault current may flow through the anti-circulation circuit to the subsequent circuits, causing damage to the subsequent circuits. Setting fuse K1 can effectively prevent the fault from expanding and protect the safety of the subsequent circuits.

[0039] (4) Improve circuit reliability: The setting of fast-blow fuse K1 enables the circuit to be quickly cut off when an overcurrent or short circuit fault occurs, preventing the fault from further deteriorating, thereby improving the overall reliability and stability of the circuit.

[0040] In addition, in the present invention, the DC-DC fuse K2 adopts a DC-DC fuse. The DC-DC fuse is a fuse specially designed for the DC to DC conversion circuit. Compared with the ordinary fuse, it better understands the working characteristics of the DC-DC conversion circuit. The DC-DC fuse usually has a lower melting current and a faster melting speed. When an overcurrent or short circuit fault occurs in the circuit, the DC-DC fuse can be quickly melted.

[0041] Furthermore, in the above, a four-level EMC filter circuit is formed by common-mode capacitors, differential-mode capacitors, and differential-mode inductors. In this way, high-voltage and high-frequency switches (such as SiC devices) will generate strong EMI. The four-level progressive filtering can significantly reduce interference with systems such as on-board chargers and BMS. The traditional four-level EMC filter circuit is generally implemented as follows: the first stage is X capacitors, common-mode inductors, and TVS diodes; the second stage is ferrite beads and TVS diodes; the third stage is a three-phase common-mode choke and Y capacitors; the fourth stage is a low-impedance grounding design of the filter connector. The four-level EMC filter circuit of the present invention is composed of common-mode capacitors, differential-mode capacitors, and differential-mode inductors, and has the following advantages:

[0042] (1) Filter out high-frequency noise introduced from the battery or DC power supply;

[0043] (2) Interference with the control signal, preventing high-frequency noise from coupling to the low-voltage control end through the drive line;

[0044] (3) Suppress the interference generated on the motor side (such as PWM harmonics and motor back EMF noise) from being fed back to the controller or power line;

[0045] Reduce the impact of switching noise on motor control accuracy (such as current sampling error and PWM waveform distortion).

[0046] In addition, a DC-DC fuse K2 is integrated at the high-voltage input end. The fuse on the DC-DC input side works together with the contactor and pre-charging circuit to prevent thermal runaway caused by a short circuit of the high-voltage battery or a failure of the DC-DC module. When a short circuit, component breakdown or load abnormality causes the current to exceed the safety threshold, the fuse quickly blows, cutting off the circuit and protecting the DC-DC converter and its load. The fuse is selected based on 1.4-1.8 times the continuous operating current and surge current of the load air conditioner.

[0047] Example 3: Reference Figure 1-Figure 3 , which is basically the same as Example 2, except that: multiple EMC capacitor mounting positions are provided at the bottom and side of the frame body, and an epoxy resin or polyurethane sealing filling layer is filled inside; the filter inductor L2 is composed of a magnetic ring arranged in the frame body, and the positive and negative copper bars pass through the magnetic ring to form an inductor structure; the grounding copper bar forms a multi-point grounding structure through the extended part of the frame body; an open mounting cavity is provided on the side of the frame body, and the common-mode capacitors CY1, CY2, CY3, and CY4 are fixed in the open cavity through a potting process and are directly welded to the extended end of the grounding copper bar; the mounting portion of the positive and negative copper bars includes a standardized interface, and an insulating isolation groove is provided at the interface, and the positive and negative pins of the DC support film capacitor C2 are connected to the copper bar interface by laser welding; the magnetic ring is made of nanocrystalline alloy, and the gap between its inner diameter and the cross-section of the positive and negative copper bars is 0.5-1 mm. The outer surface of the magnetic ring is covered with a silicone buffer layer and is fixed to the inner wall of the frame body by a snap-fit ​​structure.

[0048] In the present invention, the positive and negative copper busbars are integrated into the main frame to reduce circuit complexity; the grounding copper busbar is extended to ensure the grounding consistency of all filter capacitors and reduce common-mode interference;

[0049] The magnetic ring is used as the filter inductor L2, and the positive and negative copper busbars pass through the magnetic ring to enhance the high-frequency noise suppression capability and simplify the inductor layout;

[0050] refer to Figure 1 and Figure 2 , the inductor indicated by number 4 in the figure is the differential mode inductor L1;

[0051] Epoxy resin or polyurethane fills the side openings of the frame to improve the module's sealing, dust and water resistance, and heat dissipation efficiency;

[0052] Multiple capacitor groups (CX1-CX2, CY1-CY12) are distributed on the bottom and sides to form a three-dimensional filtering network, covering a wider interference frequency band. All common-mode capacitors (CY1-CY12) are directly connected to the grounding copper busbar inside the frame. The ends of the copper busbar extend to the outside of the module to ensure a short grounding path and consistent impedance, avoiding secondary interference caused by differences in ground loops.

[0053] The above embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patented invention. It should be noted that those skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention. These variations and improvements are equivalent modifications and improvements to the above embodiments based on the essential technology of the present invention and fall within the scope of protection of the present invention.

Claims

1. A capacitor module with integrated EMC boost, fuse, and four-stage EMC filtering functions for use in electric vehicle motor control circuits, characterized by: The capacitor module includes a frame body and integrates: EMC boost module, used to boost the input power voltage to a preset value; Fuse module, including fast-blow fuse K1 and DC-DC fuse K2; The four-stage EMC filter module is composed of the first to fourth-stage EMC filter circuits connected in sequence. The four-stage EMC filter module specifically includes: The first-level EMC filter circuit includes differential mode capacitor CX1, common mode capacitor CY1, and common mode capacitor CY2. Secondary EMC filter circuit: includes differential mode capacitor CX2, common mode capacitor CY3, common mode capacitor CY4 and differential mode inductor L1; The third-level EMC filter circuit includes common-mode capacitor CY5 and common-mode capacitor CY6; Four-stage EMC filter circuit: includes common mode capacitor CY7, common mode capacitor CY8, common mode capacitor CY9, common mode capacitor CY10, common mode capacitor CY11, common mode capacitor CY12 and DC support film capacitor C2; A circulating current prevention circuit is provided between the secondary EMC filter circuit and the tertiary EMC filter circuit. The circulating current prevention circuit is composed of a filter capacitor C1, a filter inductor L2 and a fast-blow fuse K1. The filter capacitor C1 and the DC support film capacitor C2 are arranged in parallel in the frame body. The frame body is provided with positive and negative copper bars and a grounding copper bar, wherein the positive and negative copper bars are provided with mounting portions, and both ends of the grounding copper bar extend to the outside of the frame.

2. The capacitor module integrating EMC boost, fuse and four-level EMC filtering functions according to claim 1, characterized in that: The fast-blow fuse K1 is set in the anti-circulation circuit, and the DC-DC fuse K2 is set at the high-voltage input end and works in conjunction with the contactor and the pre-charging circuit; The bottom and side of the frame body are provided with a plurality of EMC capacitor installation positions, and the interior is filled with an epoxy resin or polyurethane sealing filling layer.

3. The capacitor module integrating EMC boost, fuse and four-level EMC filtering functions according to claim 1, characterized in that: The filter inductor L2 is composed of a magnetic ring arranged in the frame body, and the positive and negative copper bars pass through the magnetic ring to form an inductor structure; The grounding copper busbar forms a multi-point grounding structure through the extension part of the frame body.

4. The capacitor module integrating EMC boost, fuse and four-stage EMC filtering functions according to claim 2, characterized in that: An open mounting cavity is provided on the side of the frame body, and the common-mode capacitors CY1, CY2, CY3 and CY4 are fixed in the open cavity by a potting process and are directly welded to the extended end of the grounding copper busbar.

5. The capacitor module integrating EMC boost, fuse and four-level EMC filtering functions according to claim 1, characterized in that: The mounting portion of the positive and negative copper busbars includes a standardized interface, and an insulating isolation groove is provided at the interface. The positive and negative pins of the DC support film capacitor C2 are connected to the copper busbar interface by laser welding.

6. The capacitor module integrating EMC boost, fuse and four-level EMC filtering functions according to claim 3, characterized in that: The magnetic ring is made of nanocrystalline alloy, and the gap between its inner diameter and the cross-section of the positive and negative copper bars is 0.5-1mm. The outer surface of the magnetic ring is covered with a silicone buffer layer and is fixed to the inner wall of the frame body by a snap-fit ​​structure.

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