Hybrid filter and electrically driven inverter

Abstract

The invention discloses a hybrid filter and an electrically driven inverter, and relates to the technical field of filters, and the hybrid filter comprises a first common-mode capacitor, a second common-mode capacitor, a differential-mode capacitor, an active differential-mode circuit unit, an active common-mode circuit unit, a common-mode filtering magnetic ring, an electromagnetic induction coil, a positive pole DC busbar, a negative pole DC busbar and a grounding pole. The first common mode capacitor is connected between the positive pole direct current busbar and the grounding pole, the second common mode capacitor is connected between the negative pole direct current busbar and the grounding pole, the differential mode capacitor is connected between the positive pole direct current busbar and the negative pole direct current busbar, and the active differential mode circuit unit is configured to be connected with the positive pole direct current busbar and the negative pole direct current busbar. The active common-mode circuit unit is configured to acquire a common-mode interference current through the electromagnetic induction coil. According to the hybrid filter, the cost of the hybrid filter is reduced, the size and space occupation of the hybrid filter are reduced, and the reliability of the hybrid filter is improved.

Description

Technical Field

[0001] This invention relates to the field of filter technology, and in particular to a hybrid filter and an electric drive inverter having the hybrid filter. Background Technology

[0002] In related technologies, the electromagnetic interference propagation paths of existing electric drive systems are complex, including common-mode interference and differential-mode interference. Existing filters suffer from problems such as large size and high cost, and their filtering effect is affected when placed in a limited space. Summary of the Invention

[0003] This invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one object of this invention is to provide a hybrid filter that is advantageous in reducing the number of components, lowering the cost, reducing the size and space occupied, improving the filtering effect while reducing the number of components, and enhancing the reliability of the hybrid filter.

[0004] The present invention also proposes an electric drive inverter using the above-mentioned hybrid filter.

[0005] According to a first aspect of the present invention, a hybrid filter includes: a first common-mode capacitor, a second common-mode capacitor, a differential-mode capacitor, an active differential-mode circuit unit, an active common-mode circuit unit, a common-mode filter magnetic ring, an electromagnetic induction coil, a positive DC bus, a negative DC bus, and a grounding post. The common-mode filter magnetic ring and the electromagnetic induction coil are electromagnetically coupled. The electromagnetic induction coil and the active common-mode circuit unit are connected. The positive DC bus and the negative DC bus are both disposed within the common-mode filter magnetic ring. The grounding post is grounded. The first common-mode capacitor is connected between the positive DC bus and the grounding post. The second common-mode capacitor is connected between the negative DC bus and the grounding post. The differential-mode capacitor is connected between the positive DC bus and the negative DC bus. The active differential-mode circuit unit is configured to be connected to both the positive DC bus and the negative DC bus to obtain a differential-mode interference signal. The active common-mode circuit unit is configured to obtain a common-mode interference current through the electromagnetic induction coil.

[0006] According to the embodiments of this application, the hybrid filter can be used for different common-mode interference suppression processes by setting a common-mode filter magnetic ring. The hybrid filter does not require an electromagnetic induction transformer, which helps to reduce the number of parts in the hybrid filter, reduce the cost of the hybrid filter, and reduce the size and space occupation of the hybrid filter. Differential-mode capacitors and active differential-mode circuit units can both be used to suppress differential-mode interference. The first common-mode capacitor, the second common-mode capacitor, the common-mode filter magnetic ring, and the active common-mode circuit unit can all be used to suppress common-mode interference. This helps to improve the filtering effect of the hybrid filter while reducing the number of parts in the hybrid filter, and also helps to improve the reliability of the hybrid filter.

[0007] According to some embodiments of the present invention, the active differential-mode circuit unit includes a differential-mode interference acquisition circuit, a differential-mode interference calculation and amplification circuit, and a differential-mode interference injection circuit. The differential-mode interference acquisition circuit, the differential-mode interference calculation and amplification circuit, and the differential-mode interference injection circuit are connected in series in sequence, and the differential-mode interference injection circuit is connected to both the positive DC bus and the negative DC bus. The active common-mode circuit unit includes a common-mode interference acquisition circuit, a common-mode interference calculation and amplification circuit, and a common-mode interference injection circuit. The common-mode interference acquisition circuit, the common-mode interference calculation and amplification circuit, and the common-mode interference injection circuit are connected in series in sequence, and the common-mode interference injection circuit is connected to the grounding post.

[0008] According to some embodiments of the present invention, the hybrid filter further includes a power supply circuit, wherein the differential-mode interference calculation and amplification circuit and the common-mode interference calculation and amplification circuit are both connected to the power supply circuit.

[0009] According to some embodiments of the present invention, the hybrid filter further includes: a PCB board, wherein the active differential mode circuit unit and the active common mode circuit unit are both disposed on the PCB board, and the first common mode capacitor, the second common mode capacitor and the differential mode capacitor are all connected to the PCB board.

[0010] According to some embodiments of the present invention, the hybrid filter further includes: a positive transmission column and a negative transmission column, wherein the positive transmission column is connected between the PCB board and the positive DC bus, and the negative transmission column is connected between the PCB board and the negative DC bus.

[0011] According to some embodiments of the present invention, the hybrid filter further includes: an isolation plate, wherein the first common-mode capacitor, the second common-mode capacitor and the differential-mode capacitor are all located on the side of the isolation plate away from the common-mode filter magnetic ring along a first direction.

[0012] According to some embodiments of the present invention, the common-mode filter magnetic ring includes a first magnetic ring body and a second magnetic ring body, the first magnetic ring body and the second magnetic ring body are connected, the first magnetic ring body and the second magnetic ring body are arranged along the first direction, and the first magnetic ring body is fixed to the isolation plate.

[0013] According to some embodiments of the present invention, the first magnetic ring body and the second magnetic ring body define a first through hole, and the positive DC bus and the negative DC bus are both disposed through the first through hole. The positive DC bus and the negative DC bus are arranged in parallel along the first direction.

[0014] According to some embodiments of the present invention, the hybrid filter further includes: a ground plane, the grounding post and the ground plane are connected, the ground plane is adapted to be connected to the housing of the electric drive inverter, and the ground plane is formed with a clearance hole, the common mode filter magnetic ring passing through the clearance hole.

[0015] According to a second aspect of the present invention, the electric drive inverter includes the hybrid filter described in the above embodiments.

[0016] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of a hybrid filter according to an embodiment of this application; Figure 2 This is an exploded view of a hybrid filter according to an embodiment of this application; Figure 3 This is another schematic diagram of a hybrid filter according to an embodiment of this application; Figure 4 This is another schematic diagram of a hybrid filter according to an embodiment of this application; Figure 5 This is a schematic diagram of a hybrid filter according to an embodiment of this application.

[0018] Figure label: Hybrid filter 1, First common-mode capacitor 11, second common-mode capacitor 12, differential-mode capacitor 13. Active differential mode circuit unit 20, differential mode interference acquisition circuit 21, differential mode interference calculation and amplification circuit 22, differential mode interference injection circuit 23 Active common-mode circuit unit 30, common-mode interference acquisition circuit 31, common-mode interference operational and amplification circuit 32, common-mode interference injection circuit 33 Common-mode filter magnetic ring 40, first magnetic ring body 41, second magnetic ring body 42, first through hole 43. Positive DC busbar 51, negative DC busbar 52, electromagnetic induction coil 53. Grounding post 61, positive power transmission post 62, negative power transmission post 63. PCB board 71, power supply circuit 72, Floor level 80, clearance hole 81 Isolation plate 91, first fixing plate 92, shell 93. Detailed Implementation

[0019] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] The following is for reference. Figures 1-5 A hybrid filter 1 according to an embodiment of the present invention is described, which can be assembled with an electric drive inverter.

[0021] According to the first aspect of the embodiment of the hybrid filter 1, such as Figures 1-5 As shown, the hybrid filter 1 may include: a first common-mode capacitor 11, a second common-mode capacitor 12, a differential-mode capacitor 13, an active differential-mode circuit unit 20, an active common-mode circuit unit 30, a common-mode filter magnetic ring 40, an electromagnetic induction coil 53, a positive DC bus 51, a negative DC bus 52, and a grounding post 61. The common-mode filter magnetic ring 40 and the electromagnetic induction coil 53 are electromagnetically coupled. The electromagnetic induction coil 53 is connected to the active common-mode circuit unit 30. Both the positive DC bus 51 and the negative DC bus 52 are inserted through the common-mode filter magnetic ring 40. Ring 40, grounding post 61 is grounded, wherein the first common mode capacitor 11 is connected between the positive DC bus 51 and the grounding post 61, the second common mode capacitor 12 is connected between the negative DC bus 52 and the grounding post 61, the differential mode capacitor 13 is connected between the positive DC bus 51 and the negative DC bus 52, the active differential mode circuit unit 20 is configured to be connected to both the positive DC bus 51 and the negative DC bus 52 to obtain differential mode interference signals, and the active common mode circuit unit 30 is configured to obtain common mode interference current through electromagnetic induction coil 53.

[0022] It should be noted that the electromagnetic interference propagation path of existing electric drive systems is complex, involving both common-mode and differential-mode interference. Existing filters suffer from problems such as large size and high cost, and their filtering effect is affected when placed in a limited space.

[0023] Based on this, this application proposes a hybrid filter 1. A first common-mode capacitor 11 and a second common-mode capacitor 12 can be used to suppress common-mode interference, and a differential-mode capacitor 13 can be used to suppress differential-mode interference. An active differential-mode circuit unit 20 can be used to suppress differential-mode interference, and an active common-mode circuit unit 30 can be used to suppress common-mode interference. A common-mode filter magnetic ring 40 can be electromagnetically coupled to an electromagnetic induction coil 53, and the electromagnetic induction coil 53 can be connected to the active common-mode circuit unit 30. The active common-mode circuit unit 30 can obtain the common-mode interference current through the electromagnetic induction coil 53, thereby achieving the effect of actively suppressing common-mode interference. The hybrid filter 1 can have a positive DC bus 51 and a negative DC bus 52. The electric drive inverter can have an inverter bridge. The positive DC bus 51 can be connected between the positive terminal of the high-voltage power supply and the input terminal of the inverter bridge, and the negative DC bus 52 can be connected between the negative terminal of the high-voltage power supply and the output terminal of the inverter bridge. The common-mode filter magnetic ring 40 can be constructed as a ring structure. Both the positive DC bus 51 and the negative DC bus 52 can be inserted into the common-mode filter magnetic ring 40. The current flowing through the positive DC bus 51 and the negative DC bus 52 can generate a magnetic field within the common-mode filter magnetic ring 40. When the magnetic fields generated by the positive DC bus 51 and the negative DC bus 52 are in the same direction, they superimpose; when the magnetic fields generated by the positive DC bus 51 and the negative DC bus 52 are in opposite directions, they cancel each other out. The grounding post 61 can be made of copper or other metallic materials. The grounding post 61 serves a conductive function and can ground the circuit.

[0024] The first common-mode capacitor 11 can be connected between the positive DC bus 51 and the grounding post 61, and the second common-mode capacitor 12 can be connected between the negative DC bus 52 and the grounding post 61. When the high-frequency common-mode interference current flows in the same direction through the positive DC bus 51 and the negative DC bus 52 into the common-mode filter magnetic ring 40, the magnetic fields generated by the currents on the positive DC bus 51 and the negative DC bus 52 within the common-mode filter magnetic ring 40 are in the same direction. The magnetic fields generated by the positive DC bus 51 and the negative DC bus 52 are superimposed, and the permeability of the common-mode filter magnetic ring 40 is significantly improved. The common-mode filter magnetic ring 40 exhibits extremely high impedance to the high-frequency common-mode interference current, and the high-frequency common-mode interference current cannot pass through the common-mode filter magnetic ring 40. The high-frequency common-mode interference current on the positive DC bus 51 flows to the first common-mode capacitor 11 and is discharged to ground through the grounding post 61. The high-frequency common-mode interference current on the negative DC bus 52 flows to the second common-mode capacitor 12 and is discharged to ground through the grounding post 61. This is beneficial for achieving the effect of the hybrid filter 1 in suppressing common-mode interference using the common-mode filter magnetic ring 40.

[0025] The differential-mode capacitor 13 can be connected between the positive DC bus 51 and the negative DC bus 52. The differential-mode capacitor 13 has the characteristic of passing high frequencies and blocking low frequencies. By connecting the differential-mode capacitor 13 between the positive DC bus 51 and the negative DC bus 52, it is beneficial to provide a low-impedance bypass path for high-frequency differential-mode interference current. High-frequency differential-mode interference current will preferentially flow through the differential-mode capacitor 13, which helps reduce the probability of high-frequency differential-mode interference current entering the core circuit of the electric drive inverter (such as the inverter bridge), helps to achieve the effect of the hybrid filter 1 in suppressing differential-mode interference, and helps to reduce the impact on normal DC current transmission.

[0026] The active differential mode circuit unit 20 can be connected to both the positive DC bus 51 and the negative DC bus 52 to obtain differential mode interference signals. The active differential mode circuit unit 20 can acquire differential mode interference voltage signals on both the positive and negative DC buses. It can amplify the differential mode interference voltage signals in reverse, with the amplified reverse voltage signal being out of phase with the original differential mode interference voltage signal. The active differential mode circuit unit 20 can convert the reverse voltage signal into a current signal, forming a compensation current. The high-frequency differential mode interference current can form a loop in the positive DC bus 51 and the negative DC bus 52. When a compensation current is injected into the loop in reverse, meaning the compensation current flows in the opposite direction to the original high-frequency differential mode interference current on the positive and negative DC buses 51 and 52, the high-frequency differential mode interference current in the loop can be significantly attenuated or even reduced to zero, which is beneficial for achieving the effect of actively suppressing differential mode interference in reverse.

[0027] The active common-mode circuit unit 30 can be connected to the electromagnetic induction coil 53. The common-mode filter magnetic ring 40 can be electromagnetically coupled to the electromagnetic induction coil 53. The electromagnetic induction coil 53 can be wound around the common-mode filter magnetic ring 40. The other end of the electromagnetic induction coil 53 away from the common-mode filter magnetic ring 40 can be connected to the active common-mode circuit unit 30. Both the positive DC bus 51 and the negative DC bus 52 can be inserted through the common-mode filter magnetic ring 40. The active common-mode circuit unit 30 can obtain the common-mode interference current through the electromagnetic induction coil 53. The common-mode filter magnetic ring 40, the positive DC bus 51, the negative DC bus 52, and the electromagnetic induction coil 53 can be used to jointly simulate the electromagnetic induction transformer in the prior art. The common-mode filter magnetic ring 40 can be regarded as the magnetic core of the electromagnetic induction transformer, the positive DC bus 51 and the negative DC bus 52 can be regarded as the primary winding of the electromagnetic induction transformer, and the electromagnetic induction coil 53 can be regarded as the secondary winding of the electromagnetic induction transformer.

[0028] It should be noted that the positive DC bus 51 and negative DC bus 52 are the main carriers of interference signals. Common-mode interference current can flow through the positive DC bus 51 and negative DC bus 52 in the same direction, while differential-mode interference current can flow through the positive DC bus 51 and negative DC bus 52 in the opposite direction. By considering the positive DC bus 51 and negative DC bus 52 as the primary windings of an electromagnetic induction transformer, there is no need to wind an independent primary coil, which simplifies the structure of the hybrid filter 1. If an independent electromagnetic induction transformer is introduced, magnetic field coupling may occur between its core and the original common-mode filter magnetic ring 40, leading to the introduction of new electromagnetic interference. Furthermore, the parasitic parameters of the newly added winding may also affect the impedance matching of the original circuit. In this application, the common-mode filter magnetic ring 40, positive DC bus 51, negative DC bus 52 and electromagnetic induction coil 53 are reused. The positions of the positive DC bus 51 and negative DC bus 52 relative to the common-mode filter magnetic ring 40 are fixed, and the magnetic field is concentrated inside the common-mode filter magnetic ring 40, which will not generate additional magnetic field coupling problems. At the same time, due to the low parasitic inductance characteristics of the positive DC bus 51 and negative DC bus 52, it is beneficial to improve the stability of the signal.

[0029] The active common-mode circuit unit 30 can convert the common-mode interference current signal into a voltage signal. The active common-mode circuit unit 30 can amplify the voltage signal in reverse. The amplified reverse voltage signal is out of phase with the original common-mode interference voltage signal. The active common-mode circuit unit 30 can convert the reverse voltage signal into a current signal. The active common-mode circuit unit 30 can generate a reverse compensation current and inject the reverse compensation current into the reference ground plane of the hybrid filter 1, thereby achieving the effect of active suppression of reverse common-mode interference.

[0030] In this embodiment, by setting the common-mode filter magnetic ring 40, different common-mode interference suppression workflows can be used. The hybrid filter 1 does not require an electromagnetic induction transformer, which helps to reduce the number of parts in the hybrid filter 1, reduce the cost of the hybrid filter 1, and reduce the size and space occupation of the hybrid filter 1. The differential-mode capacitor 13 and the active differential-mode circuit unit 20 can both be used to suppress differential-mode interference. The first common-mode capacitor 11, the second common-mode capacitor 12, the common-mode filter magnetic ring 40, and the active common-mode circuit unit 30 can all be used to suppress common-mode interference. This helps to improve the filtering effect of the hybrid filter 1 while reducing the number of parts in the hybrid filter 1, and improves the reliability of the hybrid filter 1.

[0031] In some embodiments of the present invention, such as Figure 5As shown, the active differential mode circuit unit 20 includes a differential mode interference acquisition circuit 21, a differential mode interference calculation and amplification circuit 22, and a differential mode interference injection circuit 23. The differential mode interference acquisition circuit 21, the differential mode interference calculation and amplification circuit 22, and the differential mode interference injection circuit 23 are connected in series. The differential mode interference injection circuit 23 is connected to both the positive DC bus 51 and the negative DC bus 52. The active common mode circuit unit 30 includes a common mode interference acquisition circuit 31, a common mode interference calculation and amplification circuit 32, and a common mode interference injection circuit 33. The common mode interference acquisition circuit 31, the common mode interference calculation and amplification circuit 32, and the common mode interference injection circuit 33 are connected in series. The common mode interference injection circuit 33 is connected to the grounding post 61.

[0032] The active differential-mode circuit unit 20 may include a differential-mode interference acquisition circuit 21, a differential-mode interference calculation and amplification circuit 22, and a differential-mode interference injection circuit 23. These circuits can be connected in series. The differential-mode interference acquisition circuit 21 can be connected to both the positive DC bus 51 and the negative DC bus 52. The output of the differential-mode interference acquisition circuit 21 can be connected to the input of the differential-mode interference calculation and amplification circuit 22, and the output of the differential-mode interference calculation and amplification circuit 22 can be connected to the input of the differential-mode interference injection circuit 23. The differential-mode interference injection circuit 23 is also connected to both the positive DC bus 51 and the negative DC bus 52.

[0033] The differential-mode interference acquisition circuit 21 can acquire the differential-mode interference voltage signals on the positive DC bus 51 and the negative DC bus. The differential-mode interference calculation and amplification circuit 22 can amplify the differential-mode interference voltage signal in reverse. The amplified reverse voltage signal is out of phase with the original differential-mode interference voltage signal. The differential-mode interference injection circuit 23 can convert the reverse voltage signal into a current signal, thereby enabling the active differential-mode circuit unit 20 to form a compensation current. The high-frequency differential-mode interference current can form a loop in the positive DC bus 51 and the negative DC bus 52. The differential-mode interference injection circuit 23 can inject the compensation current in reverse into the loop. That is, the compensation current flows in the opposite direction to the original high-frequency differential-mode interference current on the positive DC bus 51 and the negative DC bus 52. The high-frequency differential-mode interference current in the loop can be significantly attenuated or even reduced to zero, which is beneficial to further achieve the effect of active suppression of differential-mode interference in reverse.

[0034] The active common-mode circuit unit 30 may include a common-mode interference acquisition circuit 31, a common-mode interference operation and amplification circuit 32, and a common-mode interference injection circuit 33. The common-mode interference acquisition circuit 31, the common-mode interference operation and amplification circuit 32, and the common-mode interference injection circuit 33 may be connected in series. The input terminal of the common-mode interference acquisition circuit 31 may be connected to the electromagnetic induction coil 53. The output terminal of the common-mode interference acquisition circuit 31 may be connected to the input terminal of the common-mode interference operation and amplification circuit 32. The output terminal of the common-mode interference operation and amplification circuit 32 may be connected to the input terminal of the common-mode interference injection circuit 33. The common-mode interference injection circuit 33 may be connected to the grounding post 61.

[0035] The common-mode interference acquisition circuit 31 can acquire the common-mode interference current through the electromagnetic induction coil 53. The common-mode interference acquisition circuit 31 can convert the common-mode interference current signal into a voltage signal and transmit it to the common-mode interference calculation and amplification circuit 32. The common-mode interference calculation and amplification circuit 32 can amplify the voltage signal in reverse. The amplified reverse voltage signal is out of phase with the original common-mode interference voltage signal. The common-mode interference injection circuit 33 can convert the reverse voltage signal into a current signal. The active common-mode circuit unit 30 can form a reverse compensation current. The common-mode interference injection circuit 33 can inject the reverse compensation current into the grounding post 61, which is beneficial to further achieve the effect of active suppression of reverse common-mode interference.

[0036] By setting the active differential-mode circuit unit 20, which may include a differential-mode interference acquisition circuit 21, a differential-mode interference calculation and amplification circuit 22, and a differential-mode interference injection circuit 23, and the active common-mode circuit unit 30, which may include a common-mode interference acquisition circuit 31, a common-mode interference calculation and amplification circuit 32, and a common-mode interference injection circuit 33, it is beneficial to further realize the reverse active suppression effect of the hybrid filter 1 on differential-mode interference and common-mode interference.

[0037] In some embodiments of the present invention, such as Figure 5 As shown, the hybrid filter 1 may also include: a power supply circuit 72, a differential mode interference calculation and amplification circuit 22 and a common mode interference calculation and amplification circuit 32, both of which are connected to the power supply circuit 72.

[0038] The power supply circuit 72 can obtain power from the control board of the electric drive inverter. The input terminal of the power supply circuit 72 can be connected to a 12V power supply. Both the differential-mode interference calculation and amplification circuit 22 and the common-mode interference calculation and amplification circuit 32 can be connected to the power supply circuit 72; that is, the first output terminal of the power supply circuit 72 can be connected to the differential-mode interference calculation and amplification circuit 22, and the second output terminal can be connected to the common-mode interference calculation and amplification circuit 32. Both the differential-mode interference calculation and amplification circuit 22 and the common-mode interference calculation and amplification circuit 32 can be equipped with filter chips, thereby enabling the power supply circuit 72 to power the filter chips in the differential-mode interference calculation and amplification circuit 22 and the common-mode interference calculation and amplification circuit 32. This is beneficial for further realizing the reverse active suppression effect of the hybrid filter 1 on differential-mode interference and common-mode interference.

[0039] In some embodiments of the present invention, such as Figure 2 As shown, the hybrid filter 1 may further include: a PCB board 71, an active differential mode circuit unit 20 and an active common mode circuit unit 30, both of which are disposed on the PCB board 71, and a first common mode capacitor 11, a second common mode capacitor 12 and a differential mode capacitor 13 are all connected to the PCB board 71.

[0040] Both the active differential-mode circuit unit 20 and the active common-mode circuit unit 30 are located on the PCB board 71. That is, the differential-mode interference acquisition circuit 21, the differential-mode interference calculation and amplification circuit 22, the differential-mode interference injection circuit 23, the common-mode interference acquisition circuit 31, the common-mode interference calculation and amplification circuit 32, and the common-mode interference injection circuit 33 are all located on the PCB board 71. The first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13 can all be connected to the PCB board 71. The pins of the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13 can all be soldered to the pads on the PCB board 71, thereby shortening the lead length between the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13 and the PCB board 71. This helps to reduce the parasitic inductance of the capacitor leads, improve the filtering effect of the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13, improve the transient response rate of the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13, and improve the reliability of the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13.

[0041] As an example, the power supply circuit 72 can be located on the PCB board 71, so that both the differential mode interference operation and amplification circuit 22 and the common mode interference operation and amplification circuit 32 are connected to the power supply circuit 72.

[0042] As an example, the PCB board 71 can be located above the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13. The first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13 can support the PCB board 71. The first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13 can be placed on the same horizontal plane, which is beneficial to further reduce the volume of the hybrid filter 1 and further reduce the space occupied by the hybrid filter 1.

[0043] As an example, the electromagnetic induction coil 53 can be wound around the common-mode filter magnetic ring 40, and the other end of the electromagnetic induction coil 53 away from the common-mode filter magnetic ring 40 can be connected to the PCB board 71, so that the electromagnetic induction coil 53 can be connected to the common-mode interference acquisition circuit 31.

[0044] In some embodiments of the present invention, such as Figures 2-4 As shown, the hybrid filter 1 may further include: a positive power transmission post 62 and a negative power transmission post 63, with the positive power transmission post 62 connected between the PCB board 71 and the positive DC bus 51, and the negative power transmission post 63 connected between the PCB board 71 and the negative DC bus 52.

[0045] Both the positive terminal post 62 and the negative terminal post 63 can be constructed as copper posts, and both can conduct electricity. The positive terminal post 62 can be connected between the PCB board 71 and the positive DC bus 51, and the negative terminal post 63 can be connected between the PCB board 71 and the negative DC bus 52. This facilitates the connection of the active differential mode circuit unit 20, the first common mode capacitor 11, the second common mode capacitor 12, and the differential mode capacitor 13 on the PCB board 71 with the positive DC bus 51 and the negative DC bus 52. This is beneficial for further achieving the effect of the hybrid filter 1 in suppressing differential mode interference and common mode interference, and for further improving the reliability of the hybrid filter 1.

[0046] As an example, when the differential mode interference acquisition circuit 21 is connected to both the positive DC bus 51 and the negative DC bus 52, the differential mode interference acquisition circuit 21 can be connected to the positive DC bus 51 through the traces on the PCB and the positive power transmission column 62, and the differential mode interference acquisition circuit 21 can be connected to the negative DC bus 52 through the traces on the PCB and the negative power transmission column 63.

[0047] As an example, the upper ends of the positive pole transmission column 62 and the negative pole transmission column 63 can be fixedly connected to the PCB board 71 by bolts. The lower end of the positive pole transmission column 62 can be connected to the positive DC bus 51 by die casting, and the lower end of the negative pole transmission column 63 can be connected to the negative DC bus 52 by die casting.

[0048] In some embodiments of the present invention, such as Figure 2As shown, the hybrid filter 1 may further include: an isolation plate 91, along the first direction, wherein the first common-mode capacitor 11, the second common-mode capacitor 12 and the differential-mode capacitor 13 are all located on the side of the isolation plate 91 away from the common-mode filter magnetic ring 40.

[0049] Along the first direction, the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13 can all be located on the side of the isolation plate 91 away from the common-mode filter magnetic ring 40. When the hybrid filter 1 is as follows... Figure 1 Direction settings, first direction is Figure 1 In the Z-direction, the isolation plate 91 can isolate the first common-mode capacitor 11, the second common-mode capacitor 12, the differential-mode capacitor 13 from the common-mode filter magnetic ring 40. The isolation plate 91 can contact the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13. The isolation plate 91 can be used to assist the heat dissipation of the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13, which is beneficial to improving the heat dissipation efficiency of the first common-mode capacitor 11, the second common-mode capacitor 12, and the differential-mode capacitor 13.

[0050] As an example, the common-mode filter ring 40 can be located below the first common-mode capacitor 11, the second common-mode capacitor 12 and the differential-mode capacitor 13, and the isolation plate 91 can serve to support the first common-mode capacitor 11, the second common-mode capacitor 12 and the differential-mode capacitor 13.

[0051] In some embodiments of the present invention, such as Figure 2 and Figure 4 As shown, the common-mode filter magnetic ring 40 includes a first magnetic ring body 41 and a second magnetic ring body 42. The first magnetic ring body 41 and the second magnetic ring body 42 are connected. The first magnetic ring body 41 and the second magnetic ring body 42 are arranged along a first direction. The first magnetic ring body 41 is fixed to the isolation plate 91.

[0052] The common-mode filter magnetic ring 40 can be constructed as a split structure, comprising a first magnetic ring body 41 and a second magnetic ring body 42, which can be snap-fitted together. The first and second magnetic ring bodies 41 and 42 can be arranged along a first direction, with the first magnetic ring body 41 positioned above the second magnetic ring body 42. The first magnetic ring body 41 can be fixed to the isolation plate 91 and can be bonded to the isolation plate 91. Both the positive DC bus 51 and the negative DC bus 52 can pass through the common-mode filter magnetic ring 40. By configuring the common-mode filter magnetic ring 40 as a split structure, it is easier to assemble the common-mode filter magnetic ring 40, the positive DC bus 51, and the negative DC bus 52, thereby improving the assembly efficiency of the hybrid filter 1.

[0053] In some embodiments of the present invention, such as Figure 2 and Figure 4As shown, the first magnetic ring body 41 and the second magnetic ring body 42 define the first through hole 43. The positive DC bus 51 and the negative DC bus 52 are both inserted through the first through hole 43. The positive DC bus 51 and the negative DC bus 52 are arranged in parallel along the first direction.

[0054] The first magnetic ring body 41 and the second magnetic ring body 42 can define a first through hole 43. The first through hole 43 can penetrate the common-mode filter magnetic ring 40 along its axial direction. The positive DC bus 51 and the negative DC bus 52 can both pass through the first through hole 43, that is, the common-mode filter magnetic ring 40 can be sleeved on the positive DC bus 51 and the negative DC bus 52. The positive DC bus 51 and the negative DC bus 52 can be arranged along a first direction. The positive DC bus 51 can be located above the negative DC bus 52. The positive DC bus 51 and the negative DC bus 52 can be arranged in parallel, which helps to reduce the distributed capacitance and parasitic inductance between the positive DC bus 51 and the negative DC bus 52, and helps to reduce the probability of affecting the performance of the hybrid filter 1. The positive DC bus 51 and the negative DC bus 52 can be symmetrically centered within the common-mode filter magnetic ring 40, which helps to achieve the effect that the magnetic fields generated by the same current in the common-mode filter magnetic ring 40 can be uniformly superimposed and the magnetic fields generated by the reverse current in the common-mode filter magnetic ring 40 can cancel each other out, which helps to further improve the reliability of the hybrid filter 1.

[0055] In some embodiments of the present invention, such as Figure 1 and Figure 2 As shown, the hybrid filter 1 may further include: a ground plane 80, a grounding post 61 and the ground plane 80 connected together, the ground plane 80 being adapted to be connected to the housing of the electric drive inverter, and the ground plane 80 forming a clearance hole 81, with a common mode filter magnetic ring 40 passing through the clearance hole 81.

[0056] The grounding post 61 can be connected to the grounding plate 80. The grounding post 61 can be connected between the PCB board 71 and the grounding plate 80, and the grounding post 61 can extend along a first direction. As an example, the upper end of the grounding post 61 can be fixedly connected to the PCB board 71 by bolts, and the lower end of the grounding post 61 can be fixedly connected to the grounding plate 80 by die-casting. The grounding plate 80 is fixedly connected to the housing of the electric drive inverter by bolts, which helps to improve the connection strength between the hybrid filter 1 and the electric drive inverter while achieving the effect of common grounding for the hybrid filter 1 and the electric drive inverter. The grounding plate 80 can be formed with a clearance hole 81, which can penetrate the grounding plate 80 along the thickness direction. The common mode filter magnetic ring 40 can be inserted through the clearance hole 81, which helps to improve the structural compactness of the hybrid filter 1, further reduce the volume of the hybrid filter 1, and further reduce the space occupied by the hybrid filter 1.

[0057] As an example, when the first common-mode capacitor 11 is connected between the positive DC bus 51 and the grounding post 61, one end of the first common-mode capacitor 11 can be connected to the positive DC bus 51 via PCB traces and the positive power supply post 62, and the other end of the first common-mode capacitor 11 can be connected to the ground plane 80 via PCB traces and the grounding post 61. When the second common-mode capacitor 12 is connected between the negative DC bus 52 and the grounding post 61, one end of the second common-mode capacitor 12 can be connected to the negative DC bus 52 via PCB traces and the negative power supply post 63, and the other end of the second common-mode capacitor 12 can be connected to the ground plane 80 via PCB traces and the grounding post 61.

[0058] As an example, when the differential-mode capacitor 13 is connected between the positive DC bus 51 and the negative DC bus 52, one end of the differential-mode capacitor 13 can be connected to the positive DC bus 51 via PCB traces and the positive power supply post 62, and the other end of the differential-mode capacitor 13 can be connected to the negative DC bus 52 via PCB traces and the negative power supply post 63. When the differential-mode interference acquisition circuit 21 is connected to both the positive DC bus 51 and the negative DC bus 52, the first input terminal of the differential-mode interference acquisition circuit 21 can be connected to one end of the first common-mode capacitor 11, and the second input terminal of the differential-mode interference acquisition circuit 21 can be connected to one end of the second common-mode capacitor 12.

[0059] As an example, the hybrid filter 1 may also include a first fixing plate 92, which can be used to fix the second magnetic ring body 42. The second magnetic ring body 42 can be bonded to the first fixing plate 92. The first fixing plate 92 can be located below the second magnetic ring body 42. The first fixing plate 92 can be fixedly connected to the grounding plate 80 by bolts.

[0060] As an example, the hybrid filter 1 may also include a housing 93, which may define an installation space. The first common-mode capacitor 11, the second common-mode capacitor 12, the differential-mode capacitor 13, the common-mode filter magnetic ring 40, the electromagnetic induction coil 53, the grounding copper post, the PCB board 71, the positive power transmission post 62, the negative power transmission post 63, and the isolation plate 91 may all be located within the installation space. Parts of the positive DC bus 51, the negative DC bus 52, and the grounding plate 80 may be installed within the installation space.

[0061] According to a second aspect of the present invention, the electric drive inverter includes the hybrid filter 1 described in the above embodiments.

[0062] The electric drive inverter according to the embodiments of this application, using the hybrid inverter in the above embodiments, is beneficial to improving the reliability of the electric drive inverter and reducing costs.

[0063] Other configurations and operations of the hybrid filter 1 and the electric drive inverter according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0064] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0065] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A hybrid filter, characterized in that, include: The first common-mode capacitor (11), the second common-mode capacitor (12), and the differential-mode capacitor (13); Active differential mode circuit unit (20) and active common mode circuit unit (30); A common-mode filter magnetic ring (40) and an electromagnetic induction coil (53) are provided, wherein the common-mode filter magnetic ring (40) and the electromagnetic induction coil (53) are electromagnetically coupled, and the electromagnetic induction coil (53) is connected to the active common-mode circuit unit (30). Positive DC busbar (51) and negative DC busbar (52), both of which are connected to the common-mode filter magnetic ring (40); Grounding post (61), the grounding post (61) is grounded; The first common-mode capacitor (11) is connected between the positive DC bus (51) and the grounding post (61), the second common-mode capacitor (12) is connected between the negative DC bus (52) and the grounding post (61), the differential-mode capacitor (13) is connected between the positive DC bus (51) and the negative DC bus (52), the active differential-mode circuit unit (20) is configured to be connected to both the positive DC bus (51) and the negative DC bus (52) to obtain differential-mode interference signals, and the active common-mode circuit unit (30) is configured to obtain common-mode interference current through the electromagnetic induction coil (53).

2. The hybrid filter according to claim 1, characterized in that, The active differential mode circuit unit (20) includes a differential mode interference acquisition circuit (21), a differential mode interference calculation and amplification circuit (22), and a differential mode interference injection circuit (23). The differential mode interference acquisition circuit (21), the differential mode interference calculation and amplification circuit (22), and the differential mode interference injection circuit (23) are connected in series in sequence, and the differential mode interference injection circuit (23) is connected to both the positive DC bus (51) and the negative DC bus (52). The active common-mode circuit unit (30) includes a common-mode interference acquisition circuit (31), a common-mode interference calculation and amplification circuit (32), and a common-mode interference injection circuit (33). The common-mode interference acquisition circuit (31), the common-mode interference calculation and amplification circuit (32), and the common-mode interference injection circuit (33) are connected in series, and the common-mode interference injection circuit (33) is connected to the grounding post (61).

3. The hybrid filter according to claim 1, characterized in that, The hybrid filter (1) further includes a power supply circuit (72), wherein the differential mode interference calculation and amplification circuit (22) and the common mode interference calculation and amplification circuit (32) are both connected to the power supply circuit (72).

4. The hybrid filter according to claim 1, characterized in that, The hybrid filter (1) further includes a PCB board (71), wherein the active differential mode circuit unit (20) and the active common mode circuit unit (30) are both disposed on the PCB board (71), and the first common mode capacitor (11), the second common mode capacitor (12) and the differential mode capacitor (13) are all connected to the PCB board (71).

5. The hybrid filter according to claim 4, characterized in that, The hybrid filter (1) further includes a positive power transmission column (62) and a negative power transmission column (63), wherein the positive power transmission column (62) is connected between the PCB board (71) and the positive DC bus (51), and the negative power transmission column (63) is connected between the PCB board (71) and the negative DC bus (52).

6. The hybrid filter according to claim 1, characterized in that, The hybrid filter (1) further includes an isolation plate (91) along a first direction, wherein the first common-mode capacitor (11), the second common-mode capacitor (12) and the differential-mode capacitor (13) are all located on the side of the isolation plate (91) away from the common-mode filter magnetic ring (40).

7. The hybrid filter according to claim 6, characterized in that, The common-mode filter magnetic ring (40) includes a first magnetic ring body (41) and a second magnetic ring body (42). The first magnetic ring body (41) and the second magnetic ring body (42) are connected. The first magnetic ring body (41) and the second magnetic ring body (42) are arranged along the first direction. The first magnetic ring body (41) is fixed to the isolation plate (91).

8. The hybrid filter according to claim 7, characterized in that, The first magnetic ring body (41) and the second magnetic ring body (42) define a first through hole (43). The positive DC bus (51) and the negative DC bus (52) are both inserted through the first through hole (43). The positive DC bus (51) and the negative DC bus (52) are arranged in parallel along the first direction.

9. The hybrid filter according to claim 1, characterized in that, The hybrid filter (1) further includes: a ground plane (80), the grounding post (61) and the ground plane (80) are connected, the ground plane (80) is adapted to be connected to the housing of the electric drive inverter, and the ground plane (80) has a clearance hole (81), and the common mode filter magnetic ring (40) passes through the clearance hole (81).

10. An electric drive inverter, characterized in that, Includes the hybrid filter (1) according to any one of claims 1-9.

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