WO2022219925A1

WO2022219925A1 - Filter device and power converting device

Info

Publication number: WO2022219925A1
Application number: PCT/JP2022/007043
Authority: WO
Inventors: ジャア李; 正美野原; 宏文清水
Original assignee: 日立Astemo株式会社
Priority date: 2021-04-12
Filing date: 2022-02-21
Publication date: 2022-10-20
Also published as: JP2022162441A

Abstract

This filter device, one end of which is connected to the side of a DC power source and the other end of which is connected to the side of a power converting circuit, comprises: a positive polarity wiring; a negative polarity wiring; and a first capacitor and a second capacitor that are connected in parallel between the positive polarity wiring and the negative polarity wiring. The positive polarity wiring has, on the side of said one end, a first positive polarity connection part connected to the first capacitor and has, on the side of said other end, a second positive polarity connection part connected to the second capacitor. The negative polarity wiring has, on the side of said one end, a first negative polarity connection part connected to the second capacitor and has, on the side of said other end, a second negative polarity connection part connected to the second capacitor. The positive polarity wiring and the negative polarity wiring are crossed.

Description

Filter device and power conversion device

The present invention relates to a filter device and a power conversion device.

The power converters installed in hybrid and electric vehicles meet the independent standards established by each car manufacturer based on the high-voltage conduction noise standards added to the international standards regarding the handling of conductive noise generated by leakage current. There is a need. At the same time, along with the development of electric vehicles in which power converters are mounted, demands for miniaturization and cost reduction are increasing in recent years. Therefore, there is a strong demand for a filter device provided in a power conversion device to improve high-frequency noise attenuation performance while maintaining cost reduction and miniaturization.

As the background art of the present invention, Patent Document 1 below discloses a technique showing a structure in which an inductance component that passes low-frequency components and a resistance component that passes high-frequency components are connected in parallel in order to apply large currents.

JP 2010-273207 A

In the case of high-voltage/high-current applications such as in-vehicle inverters, it is necessary to freely control the inductance component of the DC wiring in the limited layout space due to high-voltage/high-current applications and miniaturization, and how to control the ESL (Equivalent Series Inductance) of the capacitor. The challenge is whether it is easy to match the ingredients. However, in the technique of Patent Document 1, the inductance component of the DC wiring is aligned with the ESL component of the capacitor in the limited installation space due to high voltage / large current application and miniaturization, while maintaining low cost and miniaturization. It is difficult to improve noise attenuation performance.

In view of this, it is an object of the present invention to provide a filter device and a power conversion device that combine cost reduction, miniaturization, and noise reduction.

A filter device of the present invention and a power conversion device including the same are a filter device having one end connected to a DC power supply side and the other end connected to a power conversion circuit side, comprising a positive wire, a negative wire, and the a first capacitor and a second capacitor connected in parallel between the positive electrode wiring and the negative electrode wiring; a second positive electrode connection portion connected to the second capacitor on the other end side; and the negative electrode wiring has a first negative electrode connection portion connected to the second capacitor on the one end side and a second negative electrode connecting portion connected to the second capacitor, wherein the positive electrode wiring and the negative electrode wiring intersect.

According to the present invention, it is possible to provide a filter device and a power conversion device in which cost reduction, miniaturization, and noise reduction are all achieved.

1 is a block diagram showing the overall configuration of a power converter according to an embodiment of the present invention; FIG. FIG. 2 is an equivalent circuit diagram of a noise filter for normal mode high voltage conduction noise reduction; FIG. 2 is an equivalent circuit diagram including parasitic components of the noise filter. FIG. 4 is a characteristic diagram showing insertion loss of the noise filter of FIG. 3; It is a figure which shows an example of the structure of a noise filter. FIG. 10 is an equivalent circuit diagram including parasitic components of a noise filter to which a conventional technique is applied; FIG. 7 is a characteristic diagram showing insertion loss of the noise filter of FIG. 6; It is a diagram showing the structure of the noise filter according to the first embodiment. FIG. 9 is a characteristic diagram showing insertion loss of the noise filter of FIG. 8; It is a figure which shows the structure of the noise filter concerning 2nd Embodiment. It is a figure which shows the structure of the noise filter concerning 3rd Embodiment. It is a figure which shows the comparison of a prior art, 1st Embodiment, and 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and are appropriately omitted and simplified for clarity of explanation. The present invention can also be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

The position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. in order to facilitate the understanding of the invention. As such, the present invention is not necessarily limited to the locations, sizes, shapes, extents, etc., disclosed in the drawings.

(Overall configuration of the present invention)
FIG. 1 is a block diagram showing the overall configuration of a power converter according to an embodiment of the present invention.

The power conversion device 1 (hereinafter referred to as the inverter 1) stores various circuit blocks and elements. The inverter 1 is also connected to a high-voltage battery 2 that supplies a DC high voltage, and an electric motor 6 that is driven by an AC voltage converted from the DC voltage by the inverter 1 .

The housing of the inverter 1 is a metal case and is connected to a GND plane 9 via a GND strap 8. It is placed on an insulator 7 having a height of 5 mm, for example, in compliance with the international standard CISPR25. Configuration.

The inverter 1 has a switching circuit 14 for converting DC voltage into AC voltage. The switching circuit 14 includes three unit switching circuits SW1 to SW3 having the same configuration, and switches these periodically. The unit switching circuits SW1 to SW3 are provided with insulated gate bipolar transistors (hereinafter referred to as transistors) TR1 and TR2 and diodes D1 and D2, respectively. Although not shown, the inverter 1 includes a control circuit board that generates control signals for the switching circuit 14 .

Diodes D1 and D2 are connected between the respective collectors and emitters of the transistors TR1 and TR2. The collector of the transistor TR1 is electrically connected to a positive wiring 11, which is a DC wiring, and the emitter of the transistor TR2 is electrically connected to a negative wiring 12, which is also a DC wiring. The emitter of transistor TR1 is connected to the collector of transistor TR2. A connection node connected between the emitter and the collector is an output node. W, respectively.

The flow of control signals for the inverter 1 will be explained. A switch control signal from a control circuit board (not shown) is supplied to gates of transistors TR1 and TR2 of unit switching circuits SW1 to SW3. This switch control signal controls the switching of the transistors TR1 and TR2 so as to complementarily turn them on and off. Further, the transistors TR1 and TR2 complementarily turn on/off, so that the output node periodically outputs a positive voltage and a negative voltage, that is, an AC voltage.

Note that stray capacitance (parasitic capacitance) is generated between the switching circuit 14 and the housing of the inverter 1 due to voltage fluctuations in the output section caused by the periodic on/off of the transistors TR1 and TR2. In FIG. 1, this stray capacitance is shown as stray capacitance 1-Cs.

The high voltage source impedance stabilization network (LISN) 3 will be explained. A high voltage battery 2 feeds the inverter 1 via a high voltage source impedance stabilization network (LISN) 3 . The housing 3 has a positive LISN circuit section 31 connected to the positive electrode terminal HVP of the high voltage battery 2 and a negative LISN circuit section 32 connected to the negative electrode terminal HVN of the high voltage battery 2. and are housed in a metal housing. The housing of LISN 3 is connected to GND plane 9 . The positive LISN circuit section 31 and the negative LISN circuit section 32 are electrically connected to the positive wiring 11 and the negative wiring 12 which are the DC wiring of the inverter 1 via the high voltage DC cable 4 .

The electric motor 6 will be explained. The electric motor 6 is composed of a three-phase electric motor and has a rotor and a stator (not shown). Also, the housing of the electric motor 6 is connected to the GND plane 9 . This electric motor 6 applies a three-phase AC voltage generated by the inverter 1 to three-phase coils 6-U, 6-V of U, V, and W arranged on a stator via a high-voltage AC cable 5. , 6-W. As a result, the three-phase coils 6-U, 6-V, and 6-W generate magnetic fields corresponding to the three-phase AC voltages, and the rotor rotates. In FIG. 1, stray capacitance (parasitic capacitance) generated between the three-phase coils 6-U, 6-V, 6-W and the housing of the motor 6 is shown as stray capacitance 6-Cs. Although not particularly limited, the housing of the electric motor 6 is connected to the GND plane 9 .

In the inverter 1, a smoothing capacitor Cx for smoothing the DC voltage and a noise filter device 13 are provided between the positive electrode wiring 11 and the negative electrode wiring 12. The smoothing capacitor Cx suppresses ripple voltage and ripple current generated in the

DC wirings

11 and 12, which are busbars connected to the high DC voltage, during the switching operation of the switching circuit 14. FIG. The smoothing capacitors Cx1 and Cx2 are for normal mode noise reduction. The reduction effect or attenuation performance is generally expressed by the insertion loss of the filter. The reduction mechanism by the capacitor will be described below. The principle is to suppress the outflow of noise to the outside by providing a low-impedance path between DC wirings by mounting a noise filter. Also, in order to suppress high-voltage conduction noise in a wide frequency band, generally two capacitors with different capacities connected in parallel are used.

The noise filter device 13 includes a magnetic core Lc surrounding DC wiring including a positive electrode wiring 11 and a negative electrode wiring 12, a first grounding capacitor Cy1 connected to the DC wirings 11 and 12 in a stage preceding the magnetic core Lc, a magnetic It has a second grounding capacitor Cy2 connected to the DC wirings 11 and 12 in the subsequent stage of the body core Lc. The ground capacitors Cy1 and Cy2 and the magnetic core Lc are for common mode noise reduction.

The first grounded capacitor Cy1 is composed of a grounded capacitor Cy11 connected between the positive wiring 11 and the first grounding point G1, and a grounded capacitor Cy12 connected between the negative wiring 12 and the first grounding point G1. Configured. Similarly, the second grounding capacitor Cy2 includes a grounding capacitor Cy21 connected between the positive wiring 11 and the second grounding point G2, and a grounding capacitor Cy22 connected between the negative wiring 12 and the second grounding point G2. and consists of

The noise filter device 13 attenuates the noise of the DC high voltage supplied from the high voltage battery 2 and inputs the DC high voltage to the switching circuit 14, which is the power converter. A noise current that causes noise is a current leaking from a power supply wiring or cable connected between the DC high voltage battery 2 and the inverter 1, and is a common mode current because it flows between GND.

The common mode current is due to voltage fluctuations to ground that occur during the switching operation in which the transistors TR1 and TR2 are periodically turned on/off. Due to the voltage fluctuation generated at the output of the switching circuit 14, the stray capacitance 1-Cs between the switching circuit 14 and the housing of the inverter 1 and the coils 6-U to W of the motor 6 and the housing A common mode current flows between the housings of the inverter 1 and the motor 6 through the stray capacitance 6-Cs present therebetween, and this current generates high-voltage conduction noise. Therefore, in order to reduce the high voltage conduction noise, it is necessary to reduce the common mode current. In the inverter 1, by using the configuration of the noise filter device 13, the noise current, which is the main cause of the high voltage conduction noise, is dealt with, and the noise is attenuated while complying with the high voltage conduction noise standard.

(About noise standards)
The high voltage conducted noise standard will be explained. Noise standards generally define regulation values in a frequency band from 0.15 MHz to 108 MHz. The high-voltage conduction noise standard is a standard added in CISPR25 Ed4, which is an international standard created by the International Special Committee on Radio Interference (CISPR) in October 2016. This regulates noise in the FM broadcast frequency band (76 MHz to 108 MHz), which is used in various applications, to be lower than in other frequency bands. High-voltage conduction noise, for example, may cause malfunctions of in-vehicle electrical and electronic equipment. Therefore, the amount of high-voltage conduction noise generated in the inverter 1 must be measured before shipment, and the amount of generated noise must be below the regulation value stipulated by the laws and regulations of each country and the specifications required by customers. Therefore, the inverter 1 employs the noise filter device 13 in order to conform to the high-voltage conduction noise standard and provide an effective filter configuration.

FIG. 2 is an equivalent circuit diagram of the noise filter device 13 for normal mode high voltage conduction noise reduction.

Capacitors Cx1 and Cx2 are connected in parallel to the positive DC wiring 11 and the negative DC wiring 12 . P1 and N1 are connection portions between Cx1 and positive DC wiring 11 and negative DC wiring 12, respectively, and P2 and N2 are connection portions between Cx2 and positive DC wiring 11 and negative DC wiring 12, respectively. Pin and Nin are input terminals on the positive and negative sides, respectively, and represent connections between the switching circuit 14 as a noise source and the positive DC wiring 11 and the negative wiring 12 . Similarly, Pout and Nout are output terminals on the positive and negative sides, respectively, and represent connections between the positive DC wiring 11 and the negative wiring 12 and the high-voltage DC cable 4 .

The noise reduction effect NS is expressed by the following equation (1) using an input voltage Vin (simulating a noise source) input between Pin and Nin and an output voltage Vout output between Pout and Nout. is represented by

NS=|Vout/Vin|... Formula (1)

In order to obtain the desired noise reduction effect NS, ideally, it is only necessary to select the constants of the capacitors Cx1 and Cx2 so that the impedance is low in the target frequency band. exists. For example, capacitor parts and DC wiring have parasitic inductance (hereinafter referred to as ESL) components such as lead wires.

FIG. 3 is an equivalent circuit diagram including the parasitic components of the noise filter device 13 in FIG.

In FIG. 3, the parasitic inductances of the first capacitor Cx1 and the second capacitor Cx2 are represented by equivalent series inductances Lc1 and Lc2, respectively. The inductance component of the positive DC wiring 11 between the positive connection portions P1 and P2 is an equivalent series inductance Lp1, and the inductance component of the negative DC wiring 12 between the negative connection portions N1 and N2 is an equivalent series inductance Ln1. is represented by Similarly, Lp0 is the inductance component of the positive DC wiring between Pout-P1, Lp2 is the inductance component of the positive DC wiring between Pin-P2, Ln0 is the inductance component of the negative DC wiring between Nout-N1, and Ln2 is the inductance component of the negative DC wiring between Nin-N2. is.

k1 is the coupling coefficient between inductors having inductances Lp1 and Ln1. Coupling coefficients between inductors having inductance components of Lp0 and Ln0 and Lp2 and Ln2 are not shown, but are used in actual calculations. The * marks attached to the inductors Lp1 and Ln1 indicate the direction of magnetic field generation.

The power source Gn is an AC voltage source that simulates the noise voltage generated by the switching circuit 14, and V1 is a voltmeter that measures the power source Gn. Resistors R3 and R4 simulate the internal resistance of the power supply Gn and the equivalent resistance of components connected to the output side, respectively. V2 is a voltmeter that measures the voltage across resistor R4.

FIG. 4 is a characteristic diagram showing the insertion loss of the noise filter device 13 of FIG.

In the characteristic diagram of FIG. 4, the horizontal axis indicates the frequency F (Frequency [MHz]), and the vertical axis indicates the insertion loss of the noise filter device 13, that is, the ratio of the voltages V2 and V1 shown in FIG. 3 in decibels (dB). represent. The smaller the ratio of the voltages V2 and V1, the higher the insertion loss of the filter and the better the attenuation performance.

A characteristic curve GLb1 shows changes in insertion loss with changes in the frequency F when the equivalent series inductances Lc1 and Lc2 of the capacitors Cx1 and Cx2 are respectively 0 nH. On the other hand, the characteristic curve GLb0 shows changes in the insertion loss when the equivalent series inductances Lc1 and Lc2 are each set to a typical value of 40 nH. The parameters of the circuit elements other than Lc1 and Lc2 when obtaining the characteristic curves GLb0 and GLb1 are the same.

Comparing the characteristic curves GLb0 and GLb1, the filter insertion loss of the characteristic curve GLb0 is worse than that of the characteristic curve GLb1 in the target frequency band of 20 MHz or higher. As mentioned above, the high voltage conduction noise standard defines the regulation value in the frequency band from 0.15MHz to 108MHz, and in particular, the 20MHz including the FM frequency band (76MHz to 108MHz) used in various applications In the above high frequency band, since it is regulated to be lower than other frequency bands, it is necessary to improve the insertion loss of the filter.

FIG. 5 is a diagram showing an example of the structure of a noise filter.

In this noise filter structure example, the

wirings

111 and 121 between the connecting portions are each about 10 mm long and about 15 mm wide, and the calculated inductance component is about 10 nH. These values are used to calculate the insertion loss of the filter using the equivalent circuit (Fig. 6). The calculation results are illustrated in FIG.

(Conventional technology and its problems)
FIG. 6 is an equivalent circuit diagram including parasitic components of a noise filter to which the prior art is applied.

6, in the equivalent circuit shown in FIG. 3, the connection wiring between the first capacitor Cx1 and the positive electrode wiring 11 and the connection wiring between the second capacitor Cx2 and the positive electrode wiring 11 are crossed. An example in which the first capacitor Cx1 and the second capacitor Cx2 are structurally intersected using this circuit configuration is shown in FIG. 12(b) described later.

I will explain the intention of this intersection of connection wiring. Conventionally, as a technology to offset the ESL component, there is a technology to adopt a capacitor with a short lead wire or cut the lead wire to make it shorter, but it requires the addition of custom products and cutting work, and the manufacturing of power converters A new issue arises when prices rise. To solve this problem, the circuit configuration shown in FIG. 6 is used to cancel out the ESL components.

Another important point of this configuration is that the inductance components Lp1 and Ln1 of the wiring between the connection parts can be aligned with the ESL components Lc1 and Lc2 of the capacitor. This can improve the insertion loss of the filter. For example, in the case of low-voltage, low-current applications such as control boards, most capacitors are surface mount type without lead wires, and the ESL component is about several nH. The inductance component of the wiring between the connecting parts can be matched with the ESL component of the capacitor.

However, in the case of high-voltage/high-current applications such as in-vehicle inverters, the capacitors used in noise filters are of the high-voltage type. Compared to low-voltage/low-current applications such as control boards, it is larger, and is about 40 to 50 nH. In this case, it is necessary to increase the width of the DC wiring in order to maintain thermal feasibility, and since the space for arranging the DC wiring is limited due to the demand for miniaturization, it is also necessary to shorten the bus bar. That is, the inductance component of the DC wiring tends to decrease, making it difficult to match the ESL component of the capacitor, which increases. As a result, there arises a problem that the effect of improving the insertion loss of the filter cannot be obtained. The present invention is to structurally solve this problem while utilizing the properties of the circuit shown in FIG.

FIG. 7 is a characteristic diagram showing the insertion loss of the noise filter of FIG.

A characteristic curve GLb2 shows changes in the insertion loss of the filter with changes in the frequency F when the inductors Lp1 and Ln1 are 10 nH. A characteristic curve GLb0 shows changes in insertion loss when there is no crossing wire, and is the same as GLb0 in FIG. The parameters of the circuit elements other than the wiring crossing configuration when obtaining the characteristic curves GLb0 and GLb2 are the same as those in FIG.

As shown in FIG. 7, unless the parasitic inductance and the capacitor ESL components are aligned, the effect of improving the insertion loss of the filter cannot be obtained so that the characteristic curves GLb0 and GLb2 are almost unchanged.

(First embodiment)
FIG. 8 is a diagram showing the structure of the noise filter device 13 according to the first embodiment.

FIG. 8(a) is a circuit diagram of the noise filter device 13 according to the first embodiment of the present invention, and FIG. 8(b) is a diagram showing its three-dimensional structure. In FIG. 8(a), one end (left side of FIG. 8(a)) of the circuit blocks and parts stored in the housing of the inverter 1 is connected to the DC power supply (high voltage battery 2) side, and the other end is connected to the DC power supply (high voltage battery 2) side. A noise filter device 13 is shown whose end (right side in FIG. 8(a)) is connected to the power conversion circuit (switching circuit 14) side.

A feature of the present invention is that the positive electrode wiring 111 connecting the first positive electrode connecting portion P1 and the second positive electrode connecting portion P2 and the negative electrode wiring 121 connecting the first negative electrode connecting portion N1 and the second negative electrode connecting portion N2 are provided. , is to cross. This crossing portion is laminated as shown in FIG. It is possible to control and match the ESL components Lc1 and Lc2 of the first capacitor Cx1 and the second capacitor Cx2.

FIG. 9 is a characteristic diagram showing the insertion loss of the noise filter of FIG.

A characteristic curve GLb3 employing the present invention shows changes in insertion loss with changes in the frequency F when the inductance components of Lp1 and Ln1 are approximately 40 nH, and the insertion loss is 20 dB or more in a high frequency band of 20 MHz or more. improvement effect was obtained.

(Second embodiment)
FIG. 10 is a diagram showing the structure of the noise filter device 13 according to the second embodiment. Note that FIG. 10(a) is the same as FIG. 8(a).

In FIG. 10(b), the intersections of the positive wiring 111 and the negative wiring 121 are arranged along multiple surfaces of the first capacitor Cx1 and the second capacitor Cx2, which are polyhedral capacitors. Also, when the capacitance of the capacitor Cx2 is smaller than that of the capacitor Cx1, the busbar crossing portion is along the lower surface of the capacitor Cx2. The lower surface of the capacitor Cx2 is the installation side to the case (housing of the inverter 1). As a result, the area for distributing the busbars can be further secured, and the inductance components of the positive electrode wiring 111 and the negative electrode wiring 121 can be increased.

In addition, the intersecting positive electrode wiring 111 and negative electrode wiring 121 are arranged along a plurality of surfaces of each of the first capacitor and the second capacitor, and the busbar intersections are arranged in a meandering manner. As a result, it is possible to further ensure the distribution area of the busbars.

It should be noted that, for example, the busbar intersection may be arranged along only the side surface of the capacitor on the side closer to the noise source or the side closer to the output terminal.

(Third Embodiment)
FIG. 11 is a diagram showing the structure of the noise filter device 13 according to the third embodiment. Note that FIG. 11(a) is the same view as FIGS. 8(a) and 10(a).

In FIG. 11(b), the intersection is arranged along only the side surface of the capacitor on the side closer to the noise source (power converter side). By doing so, it is possible to prevent an increase in size in the height direction.

FIG. 12 is a diagram showing a comparison between the prior art, the first embodiment, and the second embodiment. 12(a) is a noise filter having the same structure as that of FIG. 5, and FIG. 12(b) is a noise filter obtained by structuring the circuit diagram of FIG. Also, FIG. 12(c) shows the first embodiment, and FIG. 12(d) shows the second embodiment.

FIG. 12 shows the case where FIG. 12(a) and FIG. 12(b) are implemented, and FIG. 12(c) which is the first embodiment and FIG. 12(d) which is the second embodiment. ) has an increased inductance component. Furthermore, in the second embodiment in which the busbar area is larger than that in the first embodiment, the inductance component is further increased than in the first embodiment.

As can be seen from the wiring structures in FIGS. 12(c) and 12(d), the current flows in the same direction at the crossings, so magnetic fields in the same direction are generated. Therefore, the mutual coefficient and mutual inductance at this portion become positive values, and the inductance component of the entire wiring becomes larger. That is, as described above, by adjusting the area/interval of the intersection and the length/width of the wiring, the inductance component of the wiring can be controlled to match the ESL component of the capacitor. Thus, by canceling the ESL component of the capacitor, it is possible to improve the insertion loss characteristic of the filter and suppress the high frequency normal mode high voltage conduction noise.

According to the first to third embodiments of the present invention described above, the following effects are achieved.

(1) The filter device 13 has one end connected to the DC power supply side and the other end connected to the power conversion circuit side. One end of the positive electrode wiring 11 is connected to the first capacitor Cx1, and the other end is connected to the second capacitor Cx2. The negative electrode wiring 12 has a first negative electrode connection portion N1 connected to the second capacitor Cx2 on one end side and a second negative electrode connection portion N1 connected to the second capacitor Cx2 on the other end side. , and the positive wiring 11 and the negative wiring 12 cross each other. By doing so, it is possible to provide a filter device and a power conversion device in which cost reduction, miniaturization, and noise reduction are achieved in parallel.

(2) In the filter device 13, the intersections of the positive wiring 11 and the negative wiring 12 are laminated. By doing so, by adjusting the area/interval of this portion and the length/width of the wiring, the inductance components of the positive electrode wiring 11 and the negative electrode wiring 12 can be controlled, and the first capacitor Cx1 and the second capacitor Cx2 can be controlled. It can be aligned with the ESL components Lc1 and Lc2.

(3) In the filter device 13, the positive wiring 11 and the negative wiring 12 are arranged along multiple surfaces of the first capacitor Cx1 and the second capacitor Cx2, respectively. By doing so, the distribution area of the

busbars

11 and 12 can be secured.

(4) In the filter device 13, when the capacity of the second capacitor Cx2 is smaller than the capacity of the first capacitor Cx1, the positive wiring 11 and the negative wiring 12 intersect at the lower surface of the second capacitor Cx2. By doing so, the distribution area of the

busbars

11 and 12 can be secured.

(5) In the filter device 13, the intersection between the positive electrode wiring 11 and the negative electrode wiring 12 meanders. By doing so, the distribution area of the

busbars

11 and 12 can be secured.

(6) In the filter device 13, the inductance between the positive wire 11 and the negative wire 12 is substantially equal to the inductance of the first capacitor Cx1 or the second capacitor Cx2. By doing so, the insertion loss of the filter can be improved.

It should be noted that the present invention is not limited to the above embodiments, and various modifications and other configurations can be combined without departing from the scope of the invention. Moreover, the present invention is not limited to those having all the configurations described in the above embodiments, and includes those having some of the configurations omitted. For example, in the above-described embodiment, a power conversion device mounted on a vehicle such as a hybrid vehicle or an electric vehicle has been described as an example, but the present invention is not limited to these, but the power conversion device used in construction machinery and the like and railway vehicles. It can also be applied to devices.

1... Power converter (inverter)
1-Cs: Switching circuit/stray capacitance between cases 2: High voltage battery 3: High voltage source impedance stabilization network (LISN)
31 Positive pole LISN circuit section 32 Negative pole LISN circuit section 4 High voltage DC cable 5 High voltage AC cable 6 Electric motor 6-U U phase coil 6 V V phase coil 6 W W phase coil 6 -Cs... Stray capacitance between coil and case 7... Insulator 8... GND strap 9... GND plane 10... Current 10a... Reverse current 10b... Same direction current 11... Positive electrode (DC) wiring 12... Negative electrode (DC) Wiring 13 Noise filter device 14 Switching circuit 111 Positive wiring 121 connecting first positive connecting portion P1 and second positive connecting portion P2 Connecting first negative connecting portion N1 and second negative connecting portion N2 Negative electrode wiring SW1 to SW3 Unit switching circuits TR1, TR2 Insulated gate bipolar transistors D1, D2 Diode Cx Smoothing capacitor Gn Power supply Lc Magnetic cores Lc1, Lc2 Equivalent series inductance Lp0 to Lp3 Equivalent series inductance ( positive electrode wiring)
Ln0 to Ln3 ... Equivalent series inductance (negative wiring)
k1 Coupling coefficients between positive DC wiring and negative DC wiring Cy1, Cy2 Grounding capacitors Cy11, Cy21 Grounding capacitors between positive DC wiring and housing Cy12, Cy22 Grounding capacitors between negative DC wiring and housing Cx1 Positive electrode A first capacitor Cx2 between the DC wiring and the negative DC wiring... A second capacitor P1 between the positive DC wiring and the negative DC wiring... A first positive connecting part P2 which is a connecting part between the first capacitor Cx1 and the positive wiring 11... A second capacitor A second positive connection portion N1, which is a connection portion between Cx2 and the positive electrode wiring 11. A first negative connection portion N2, which is a connection portion between the first capacitor Cx1 and the negative electrode wiring 12. Second negative electrode connection

Claims

A filter device having one end connected to a DC power supply side and the other end connected to a power conversion circuit side,
a positive wiring, a negative wiring, and a first capacitor and a second capacitor connected in parallel between the positive wiring and the negative wiring,
The positive electrode wiring has a first positive electrode connection portion connected to the first capacitor on the one end side and a second positive electrode connection portion connected to the second capacitor on the other end side,
the negative electrode wiring has a first negative electrode connection portion connected to the second capacitor on the one end side, and a second negative electrode connection portion connected to the second capacitor on the other end side;
The filter device, wherein the positive wiring and the negative wiring intersect.
A filter device according to claim 1,
A crossing portion of the positive electrode wiring and the negative electrode wiring is laminated. The filter device.
A filter device according to claim 2,
The positive wiring and the negative wiring are arranged along multiple surfaces of the first capacitor and the second capacitor, respectively.
A filter device according to claim 2,
When the capacity of the second capacitor is smaller than the capacity of the first capacitor, the positive wiring and the negative wiring cross each other on the lower surface of the second capacitor.
A filter device according to claim 2,
The intersection is meandering. The filter device.
A filter device according to claim 1,
An inductance between the positive electrode wiring and the negative electrode wiring is substantially equal to an inductance of the first capacitor or the second capacitor.
A power converter comprising the filter device according to any one of claims 1 to 6.