JP4066909B2 - Inverter capacitor connection structure - Google Patents

Description

  The present invention relates to a capacitor connection structure used in a DC circuit portion of an inverter.

A so-called automotive power electronics system for obtaining mechanical energy from electrical energy in an electric vehicle mainly includes a battery for supplying DC power, an inverter for converting DC to AC, and a rotational force from the electrical output of the inverter. It is comprised from the motor which obtains. The inverter includes a group of switches made of power semiconductor elements in a casing. By opening and closing the switches, the inverter generates AC power for obtaining a desired rotational force from the DC power. Further, the motor obtains a rotational force by an electromagnetic action by the AC power output from the inverter.
A smoothing capacitor that absorbs fluctuations in the input voltage of the inverter is connected to the inverter. The smoothing capacitor is connected to a power line connecting the battery and the inverter.
JP-A-5-315205

In a power electronics system, as the power capacity of a motor increases, a smoothing capacitor having a larger capacity is required. Therefore, as a method of increasing the capacity of the smoothing capacitor, a method of connecting a plurality of capacitors in parallel is generally used. However, when a plurality of capacitors are connected in parallel, there is a problem in that the conductive member connecting the electrode terminals of the capacitor becomes long and the inductance component increases.
As a method for solving such a problem, a method described in Patent Document 1 is known. In this method, there is a first conductive member that connects positive terminals of a plurality of capacitors and a second conductive member that connects negative terminals, and one end of the first conductive member is folded back to face the second conductive member. It is the structure which has the 3rd electrically-conductive member to be made. It is possible to reduce the inductance component of the connecting member of the capacitor by causing the directions of the currents flowing through the three conductive members to flow in opposite directions.

However, the conventional inverter capacitor connection structure has another problem as follows. Generally, a smoothing capacitor for an electric vehicle has a capacitance component and a parasitic inductance component, and therefore has an electrical self-resonance characteristic due to these components.
The self-resonant frequency of a film capacitor or an electrolytic capacitor used as a smoothing capacitor for an electric vehicle is about 100 kHz.
On the other hand, an inverter for an electric vehicle uses an internal semiconductor switch to convert direct current into three-phase alternating current and supply power to the motor. Therefore, a harmonic current having a frequency that is an odd multiple of the carrier frequency appears as a noise current, and the amplitude of the low-order harmonic current is large. The carrier frequency of the inverter of the electric vehicle is approximately several kHz to several tens of kHz.

Further, the distance between the battery and the inverter in an electric vehicle is generally about 1 to several meters, and therefore the loop formed by the power line connecting both is relatively large. When the noise current flows into a relatively large loop formed by the power line from the battery, radioactive noise is generated from the loop.
When the above noise current is generated from the inverter, if the impedance on the capacitor side is sufficiently lower than the impedance on the battery side at the frequency of the noise current, the amount of noise current flowing into the loop formed by the power line will be reduced. In this case, since the resonance frequency at which the impedance of the capacitor becomes a minimum value and the carrier frequency of the inverter are shifted, the noise current flowing into the loop of the power supply line cannot be effectively suppressed.

  The resonance frequency of the capacitor can be moved to the carrier frequency side, that is, to a low frequency by increasing the capacitance of the capacitor. However, this causes a problem that the power electronics system itself becomes large.

  In order to solve the above problems, the present invention minimizes an increase in the volume of the power electronics system itself, and a power line that forms a relatively large loop in which a large amplitude noise current generated from an inverter is connected from a battery. It is an object of the present invention to provide an inverter capacitor connection structure that can suppress the flow of noise into the inverter and the generation of radioactive noise from the loop.

Therefore, the present invention provides an inverter system including an inverter, a capacitor, and a battery, a first conductive member having one end connected to the electrode terminal of the capacitor and the other end connected to the electrode terminal of the inverter; The second conductive member is arranged in parallel with a gap between the first conductive member and one end of the second conductive member electrically connected to one end of the first conductive member. The other end of the second conductive member is a power line. The gap between the first conductive member and the second conductive member is connected to the battery, the capacitance component of the capacitor, and the parasitic inductance component of the capacitor between the first conductive member and the second conductive member. that the mutual inductance of the resonance frequency due to the inductance component addition is set so as to be in the vicinity of the carrier frequency in the PWM control of the inverter caused It was.

  The directions of currents flowing through the first conductive member and the second conductive member are opposite to each other. Therefore, a mutual inductance component due to electromagnetic coupling is generated between the first conductive member and the second conductive member, and the self-inductance component of each of the first conductive member and the second conductive member is reduced, and the equivalent of the capacitor is reduced. The series inductance (ESL) component can be increased.

And since the self-resonance frequency of the capacitor determined by the parasitic inductance component and capacitance component of the capacitor itself is set in a direction approaching the carrier frequency of the inverter by increasing the equivalent series inductance component, the impedance on the capacitor side is set to the carrier frequency. It can be reduced in the vicinity, and radiated noise can be reduced from the loop formed by the power supply line.

Embodiments of the present invention will be described below.
FIG. 1 is a diagram showing a capacitor connection structure of an inverter of a power electronics system for an electric vehicle according to an embodiment. FIG. 2 is a perspective view showing the entire inverter system including an inverter, a capacitor, and a battery. Note that an output line for supplying three-phase alternating current from the inverter to the motor is omitted.
The electrode terminals 25 and 26 on the positive side of the capacitor 1 and the inverter 2 protrude from the respective cases, and female screws are provided on the upper surfaces of the electrode terminals 25 and 26 so that they can be connected with screws.

The conductive member 30 made of a flat conductor is connected to the electrode terminal 25 of the capacitor 1 by screw fixing on one end side and connected to the electrode terminal 26 of the inverter 2 by screw fixing on the other end side.
The conductive member 20 made of a flat plate-like conductor is arranged in parallel with the flat plate surfaces facing each other with a gap distance d from the conductive member 30, and is made of a flat plate-like conductor on one end side (capacitor 1 side). The connecting member 22 is connected to the conductive member 30.
The other end (end on the inverter 2 side) of the conductive member 20 includes a connection portion 21, and the connection portion 21 is connected to the electrode terminal of the battery 3 by the power line 10.
The conductive members 20 and 30 and the connection member 22 have a structure in which the cross-sectional area of the conductor is large and the resistance is sufficiently small as compared with the power supply line 10.

An insulating member 40 is installed between the conductive members 20 and 30.
The conductive member 30 is provided with a screw hole 51 corresponding to the electrode terminal 25, and the screw 31 inserted into the screw hole is screwed into the electrode terminal 25.
A work hole 53 for assembling the screw 31 is formed in the conductive member 20 and the insulating member 40 so as to correspond to the electrode terminal 25. The diameter of the work hole 53 is a size through which the head of the screw 31 passes, and the diameter of the screw hole 51 is a size through which the screw portion of the screw 31 passes.
Similarly, a screw hole 51 and a work hole 53 are formed at positions corresponding to the conductive member 30, the insulating member 40, and the electrode terminal 26 of the conductive member 20, and the screw 31 is screwed into the electrode terminal 26.
The conductive members 20 and 30, the connecting member 22, and the insulating member 40 are similarly attached between the negative electrode terminals of the capacitor 1 and the inverter 2.

The distance d between the conductive members 20 and 30 is determined so that the resonance frequency of the capacitor 1 is in the vicinity of the carrier frequency of the inverter 2.
A switch group made of power semiconductor elements is contained in the casing of the inverter 2. The inverter carrier frequency fc is several kHz to several tens of kHz.

The operation of this embodiment will be described below.
The inverter 2 converts direct current into three-phase alternating current by an internal semiconductor switch and supplies power to a motor (not shown). When a switch group composed of power semiconductor elements of the inverter 2 is opened and closed, a noise current due to switching is generated. This noise current is a harmonic current having a frequency that is an odd multiple of the carrier frequency fc.
FIG. 3 shows the frequency spectrum of the noise pulse by switching, the horizontal axis indicates the frequency of the noise current, and the vertical axis indicates the intensity (spectrum intensity) of the noise current. Since the harmonic intensity of the carrier frequency fc is attenuated by 20 dB / dec, it can be seen that the effect of suppressing the noise current is large when the resonance frequency by the capacitor is adjusted so that the carrier frequency fc having the highest intensity is obtained.

FIG. 4 is a diagram showing an equivalent circuit of connection between the capacitor, the inverter and the battery shown in FIG.
The conductive members 20 and 30 are opposed to each other, and currents flow in opposite directions. Therefore, the conductive members 20 and 30 are electromagnetically coupled to generate a mutual inductance M.
The capacitor 1 has a parasitic inductance component Lc. The conductive members 20 and 30 each have an inductance component LM (the difference between the self-inductance L and the mutual inductance M between the conductive members 20 and 30).
The capacitor 1 increases in inductance by the mutual inductance M in series with the parasitic inductance Lc.

The power supply line 10 has an inductance component Lp, and has a sufficiently large value compared to the inductance components Lc, LM, and M.
Further, the power supply line 10 has a resistance Rp, and the resistance Rp has a sufficiently large value as compared with the resistance of other parts of the circuit.
The inductance components Lc and M and the capacitance component C of the capacitor 1 constitute resonance characteristics.

Next, the mutual inductance and resonance characteristics of the conductive member will be described with reference to FIGS.
FIG. 5 shows a state in which two conductive members having a width W, a thickness H, and a length D are opposed to each other at a distance d. 6, the horizontal axis represents the ratio D / W between the length D and the width W, and the vertical axis represents the mutual inductance (nH) per unit length. The ratio between the thickness H and the width W of the conductive member shown in FIG. When H / W is 0.25, the characteristic of mutual inductance is expressed using the ratio d / W of distance d to width W as a parameter.
From this figure, it can be seen that the longer the length D with respect to the width W of the conductive member and the shorter the distance d between the two conductive members with respect to the width W of the conductive member, the mutual inductance component per unit length (coupling force). ) Is large.

  For example, as a simplified model of the embodiment of FIG. 1, the conductive members 20 and 30 each have a width W: about 2 cm, a thickness H: about 0.2 mm, a length D: about 10 cm, and a self-inductance of about 25 nH. Then, it is assumed that the distance d is about 2.5 mm and the capacitor 1 is connected with a film capacitor having a parasitic inductance of about 150 μF and a parasitic inductance of tens of nH, for example.

In that case, the mutual inductance component of the two conductive members 20 and 30 is about 22 nH, and the coupling coefficient is close to 0.9. Since this mutual inductance component is added to the inductance component on the capacitor 1 side, the resonance frequency is reduced from a resonance frequency of several tens of kHz to about 65 kHz only from the capacitor.
Therefore, with the size of the conductive member, it is possible to easily bring the resonance frequency to a frequency range of about 60 kHz to about 100 kHz by changing the distance between the two conductive members.

FIG. 7 shows the frequency characteristics of the current flowing into the connection part when an alternating current (noise current) flows from the electrode terminal of the inverter to the connection part via the capacitor.
The horizontal axis represents the frequency (10 k to 50 kHz), the vertical axis represents the current I _P1 of the connection portion 21 (indicated by P1 in the equivalent circuit of FIG. 4) and the current I _P2 at the terminal 26 (indicated by P2 in the equivalent circuit of FIG. 4). The ratio I _P1 / I _P2 (1 μm to 10 m (millimeters)) is shown in a log-log graph.
In the case of (1), the conductive member 20 and the connecting member 22 are omitted, and the end of the conductive member 30 on the capacitor 1 side is connected to the battery 3. The cases of (2) and (3) are shown in FIG. The case of the connection in this Embodiment is shown. Here, the difference between the cases (2) and (3) is that the distance d between the conductive members is larger in the case (2) than in the case (3).

Comparing each case, the case where the mutual inductance component exists in the conductive member (2), the case of (3), the normal number of inverters 2 kHz than the case of (1) when the conductive member does not have the mutual inductance component It can be seen that the current flowing into the connecting portion 21 can be suppressed in the low-order harmonic frequency region of the carrier frequency fc of about tens of kHz.
The conductive member 30 of the present embodiment constitutes the first conductive member of the present invention, and the conductive member 20 constitutes the second conductive member.

As described above, according to the present embodiment, the mutual inductance component M decreases the self-inductance component of the conductive members 20 and 30 and increases the inductance (ESL) component in series with the capacitor 1.
Therefore, the self-resonance characteristic of the capacitor 1 can be changed to the low-frequency carrier frequency fc side by setting the distance d.

  That is, in the noise current generated from the inverter 2, the frequency component (see FIG. 3) having a large intensity can be absorbed by the capacitor 1. As a result, the noise current is prevented from flowing into the power supply line 10 having a relatively large loop area, and the radioactive noise generated from the loop is suppressed.

Next, modifications of the present embodiment will be described below.
FIG. 8 is a diagram showing a first modification. (A) is a whole perspective view, (b) is an enlarged view of the side surface on the capacitor terminal side.
In this modification, a conductive member 4 is used in which a flat plate-like conductor is bent into a U-shape. One end side (the U-shaped bent portion side) of the lower lateral portion of the conductive member 4 is disposed on the electrode terminal side of the capacitor 1, and a screw is attached to the electrode terminal of the capacitor 1 at the bent portion end as shown in FIG. The other end is connected to the electrode terminal of the inverter 2 with screws.
The U-shaped upper horizontally long portion of the conductive member 4 is folded back toward the inverter 2 and has a connection portion 21 at the end thereof.

Since the bent portion on the capacitor 1 side is bent at a predetermined angle, for example, α, β, γ, to ensure the distance d between the vertically long portions facing each other, the manufacturing is possible. Easy and cost saving.
By adjusting the distance d, the mutual inductance M between the vertically long portions of the conductive member 4 can be adjusted.
The conductive member 4 may be formed by bending the bent portion with a predetermined radius R.

FIG. 9 is a diagram showing a second modification. (A) is a whole perspective view, (b) is an enlarged view of the side surface on the capacitor terminal side.
The difference from the embodiment is that instead of connecting the conductive members 20 and 30 in a U-shape with the connection member 22, two connection members 22 ′ made of a flat conductor having hinges 27 at both ends are provided. It is the point which used the electroconductive member 20 and 30 and used the hinge connection, and comprised the whole in the U-shape.
The hinge 27 is disposed between the connection members 22 ′, between the connection member 22 ′ and the conductive member 20, and between the connection member 22 ′ and the conductive member 30, and between the connection members 22 ′ or the connection member 22 ′. The conductive members 20 and 30 are electrically connected, and the mounting angle is variable.

The angle formed by the connection member 22 ′, the hinge 27, and the conductive member 20 is α, the angle formed by the connection member 22 ′ and the hinge 27 is β, and the angle formed by the connection member 22 ′, the hinge 27, and the conductive member 30. By setting the angle to γ and changing the angles α, β, and γ, the distance d between the conductive members 20 and 30 can be set to a predetermined value.
In this configuration, when there are variations in the characteristics of each device in the power electronics system, for example, the capacitor capacitance component C and the parasitic inductance Lc, the mutual inductance component M can be appropriately adjusted even after the system is assembled.

FIG. 10 is a diagram showing a third modification. (A) is a whole perspective view, (b) is an enlarged view of a cross section on the capacitor terminal side.
The difference from the embodiment is that the conductive members 20 and 30 are electrically connected by a screw-type connection member 28 as shown in FIG. At the same time, the electrode terminal 25 of the capacitor 1 is also connected.
The screw-type connecting member 28 is screwed into the electrode terminal 25, and the conductive member 20, the insulating member 40, and the conductive member 30 are tightened.

Corresponding to the electrode terminal 25, the conductive member 20, the insulating member 40, and the conductive member 30 are formed with screw holes 51 having a size through which the screw portion of the screw-type connecting member 28 passes.
The conductive member 20 is electrically connected to the head of the screw type connection member 28 and is connected to the electrode terminal 25 via the screw type connection member 28. The conductive member 30 is electrically connected to the electrode terminal 25 by being tightened and brought into contact with the electrode terminal 25. As a result, the screw-type connection member 28 functions as both the connection member 22 and the fixing screw 31 in the embodiment.
The mutual inductance component M due to electromagnetic coupling can be adjusted by changing the thickness d of the insulating member 40 and adjusting the distance d by the screw-type connecting member 28.
In this configuration, when the characteristics of each device of the power electronics system vary, it is possible to appropriately adjust the mutual inductance component even after the system is assembled.

In the embodiment and the first to third modifications, the insulating member 40 has a single block shape, but may be an insulating member 40 ′ in which thin plate-like insulators 42 are stacked as shown in FIG. .
When the thickness per insulator 42 is t and the number is n, the product is the thickness T of the insulating member 40 '. As a result, the insulating member 40 ′ can set the distance between the conductive members 20 and 30 to a desired value.

FIG. 12 is a view of the fourth modification viewed from above.
The difference from the embodiment is that the two U-shaped conductors formed of the conductive members 20 and 30 and the connection member 22 are arranged with the flat plate portion in the vertical direction, and the positive electrode side indicated by (+) in FIG. Between the negative electrode side electrode terminals 25 ′ and 26 ′ between the capacitor 1 and the positive electrode side electrode terminals 25, 26 of the inverter 2 with the conductive members 30 of the U-shaped conductors on the negative electrode side indicated by (−). The conductive members 20 are connected to each other with a gap therebetween.
The conductive members 30 of the two U-shaped conductors are fixed to the respective electrode terminals on the positive electrode side and the negative electrode side of the capacitor 1 and the inverter 2 via connection pieces 35 having screw holes.
The connection piece 35 is provided on the outer side in an L-shape at the lower ends of both ends of the conductive member 30 on the capacitor 1 side and the inverter 2 side.
The insulating member 40 is installed between the conductive members 20 and 30, and the insulating member 40A is installed between the conductive members 20.

Since the connection piece 35 provided outside the conductive member 30 is screwed to the electrode terminals 25, 26, 25 ′, 26 ′ of the capacitor 1 and the inverter 2 as described above, the operation of the conductive member 20 is performed as in the embodiment. The screw can be fixed in a more open space than the screw 31 is fixed through the hole 53, and the operation is easy.
In addition, the direction of the current flowing through the conductive member 20 and the direction of the current flowing through the conductive member 30 are opposite to each other and are electromagnetically coupled. In addition, current flows between the two conductive members 20 in opposite directions. It is electromagnetically coupled.

Since the electromagnetic coupling between the conductive members 20 and 30 and the conductive members 20 and 20 is used, when the dimensions of the conductive members 20 and 30 and the distance d are the same as those in the embodiment of FIG. The degree of reduction of the inductance component on the members 20 and 30 side is further increased than in the embodiment.
Therefore, when the same mutual inductance M is obtained, the space occupied by the conductive member can be made smaller than in the embodiment of FIG. 1, and the resonance frequency of the capacitor 1 can be brought closer to the carrier frequency of the inverter 2 efficiently. .

13 and 14 are views showing a fifth modification of the present invention. 13A is a cross-sectional view between the capacitor and the positive electrode of the inverter, and FIG. 13B is a cross-sectional view taken along the line AA in FIG. FIG. 14 is an overall perspective view.
In particular, as shown in FIG. 13 (b), each of the conductive members 20 and 30 and the connecting member 22 are connected between the positive electrode terminal and the negative electrode terminal 2 of the capacitor 1 and the inverter 2. Each set of conductors has a wide width across the positive electrode terminal 25 and the negative electrode terminal 25 ′.

Two sets of conductors are connected between the electrode terminals on the positive electrode side (indicated by (+) in the figure, hereinafter simply referred to as the positive electrode side) and connected between the electrode terminals on the negative electrode side ( In the figure, (−) is attached, and the conductive member 30 is vertically stacked with the insulating member 40A facing each other with the insulating member 40A interposed therebetween, with the negative electrode side hereinafter.
An insulating member 40 is sandwiched between the conductive members 20 and 30 in the respective conductors on the positive electrode side and the negative electrode side, and an insulating member 40B is also sandwiched between the conductive member 20 on the negative electrode side and the capacitor 1 and the inverter 2, respectively.

The positive-side conductive member 30 and the insulating member 40A are provided with screw holes 51 corresponding to the electrode terminals 25 and 26, and the screw-type connecting member 28a inserted into these screw holes 51 is screwed into the electrode terminals 25 and 26. It is. As a result, the positive electrode side conductive member 30 and the negative electrode side conductor and the like are clamped and fixed to the capacitor 1 and the inverter 2 at the head of the screw-type connecting member 28a, and the positive electrode side conductive member 30 is fixed to the electrode terminals 25 and 26. Connect electrically.
A working hole 53 for assembling each screw type connecting member 28a is formed through the positive electrode side conductive member 20 and the insulating member 40, and a screw type through the negative electrode side conductive members 30, 20 and the insulating members 40 and 40B. In order to avoid contact with the connecting member 28a and the electrode terminals 25 and 26, an insulating hole 52 having substantially the same diameter as the work hole is formed.

The negative electrode side conductive member 30 and the insulating member 40 are provided with screw holes 51 corresponding to the electrode terminals 25 ′ and 26 ′, and the screw type connection members 28 b inserted into these screw holes 51 are connected to the electrode terminals 25 ′, Screwed into 26 '. This clamps and fixes the negative-side insulating member 40 and below from the negative-side conductive member 30 to the capacitor 1 and the inverter 2 at the head of the screw-type connecting member 28b, and also connects the negative-side conductive member 30 to the electrode terminal 25 ′, 26 'is electrically connected.
A working hole 53 for assembling each screw type connection member 28b is formed through the insulating member 40A from the conductive member 20 on the positive electrode side, and the screw type connection member 28b and the conductive member 20b and the insulating member 40B on the negative electrode side. An insulating hole 52 is formed to avoid contact with the electrode terminals 25 ′ and 26 ′.

Thus, the electric current which flows through the electrically-conductive member 20 by the two conductors which shape | molded the electrically-conductive members 20 and 30 and the connection member 22 on the upper and lower sides, and the electrically-conductive member 30 mutually opposes via an insulating material. The direction of the current and the direction of the current flowing through the conductive member 30 are not opposite to each other and are electromagnetically coupled. In addition, current flows between the two conductive members 30 in the opposite directions and is electromagnetically coupled.
Since not only the conductive members 20 and 30 but also the electromagnetic coupling between the conductive members 30 and 30 is used, when the dimensions of the conductive members 20 and 30 and the distance d are the same as those in the embodiment of FIG. 1 and the degree of decrease of the inductance component on the conductive members 20 and 30 side is further increased as compared with the embodiment of FIG.
Therefore, when the same mutual inductance M is obtained, the space occupied by the conductive member can be made smaller than in the embodiment of FIG. 1, and the resonance frequency of the capacitor 1 can be brought closer to the carrier frequency of the inverter 2 efficiently. .

FIG. 15 is a diagram showing a sixth modification of the present embodiment.
In this modification, it is a figure which shows the capacitor | condenser connection structure of an inverter in case the electrode terminal of the positive electrode side of the capacitor | condenser 1 and the inverter 2 has come out from the opposite surface of each case. In the figure, (+) is attached to the U-shaped conductor on the positive electrode side, and (-) is added to the U-shaped conductor on the negative electrode side.
In each of the conductors on the positive electrode side and the negative electrode side, the conductive member 30 is connected to the electrode terminal of the capacitor 1 by screw fixing at one end side and is connected to the electrode terminal of the inverter 2 by screw fixing at the other end side. The conductive member 20 is disposed parallel to the conductive member 30 with the gap between the conductive plates 30 facing each other, and is connected to the conductive member 30 by the connecting member 22 at the end on the capacitor 1 side. The other end of the conductive member 20 includes a connection portion 21, and the connection portion 21 is connected to the battery electrode terminal by the power supply line 10. An insulating member (not shown) is disposed between the conductive members 20 and 30.

  As described above, even when the surfaces of the case where the capacitor and the electrode terminal of the inverter are provided are different, mutual inductance M is generated between the conductive members 20 and 30 by electromagnetic coupling similarly to the embodiment, and the resonance of the capacitor The frequency can be changed around the carrier frequency fc.

  In the above embodiment and modification, the symmetrical structure is shown so that the noise current generated from the inverter 2 can be dealt with regardless of which side of the positive electrode side or the negative electrode side is generated. However, the pole of the generated noise current is known. In this case, the conductor 4 of the above-described embodiment or its modification may be used only for the pole.

It is a figure which shows the structure of embodiment of this invention. 1 is an overall perspective view of an embodiment. It is a figure which shows the frequency spectrum of the noise electric current which generate | occur | produces from an inverter. It is a figure which shows an equivalent circuit. It is a figure explaining the mutual inductance characteristic between two flat plate-shaped electrically-conductive members put in parallel. It is a figure explaining the mutual inductance characteristic between the two electrically-conductive members put in parallel. It is a figure which shows the frequency characteristic of the noise current which flows into an electric power line from an inverter. It is a figure which shows the 1st modification of embodiment. It is a figure which shows the 2nd modification of embodiment. It is a figure which shows the 3rd modification of embodiment. It is a figure which shows the shape of the insulating member used by embodiment and its modification. It is a figure which shows the 4th modification of embodiment. It is sectional drawing of the 5th modification of embodiment. It is a perspective view of the 5th modification of embodiment. It is a figure which shows the 6th modification of embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Capacitor 2 Inverter 3 Battery 4 Conductive member 10 Power supply line 20, 30 Conductive member 21 Connection part 22, 22 'Connection member 25, 25', 26, 26 'Electrode terminal 27 Hinge 28, 28a, 28b Screw type connection member 31 Screw 35 Connection piece 40, 40 ', 40A, 40B Insulating member 42 Insulator 51 Screw hole 52 Insulating hole 53 Working hole

Claims (10)

In an inverter system composed of an inverter, a capacitor and a battery,
A first conductive member having one end connected to the electrode terminal of the capacitor and the other end connected to the electrode terminal of the inverter;
The first conductive member is arranged in parallel with a gap, and one end is composed of a second conductive member electrically connected to the one end of the first conductive member,
While the other end of the second conductive member is connected to the battery by a power line ,
The distance between the first conductive member and the second conductive member is defined as the mutual inductance component generated between the first conductive member and the second conductive member in the capacitance component of the capacitor and the parasitic inductance component of the capacitor. A capacitor connection structure for an inverter , wherein a resonance frequency due to an inductance component added to the inverter is set to be near a carrier frequency in PWM control of the inverter. 2. The inverter capacitor connection structure according to claim 1, wherein the first and second conductive members are made of a flat plate-like conductor. 3. 3. The inverter according to claim 1, wherein the first and second conductive members are formed of an integral conductive member, and are configured by folding a flat plate-like conductor into a U-shape . Capacitor connection structure. 3. The capacitor connection structure for an inverter according to claim 1 , wherein the one ends of the first and second conductive members are electrically connected by a screw-type connection member . 4. 5. The capacitor connection structure for an inverter according to claim 1 , wherein the first conductive member and the second conductive member are opposed to each other with an insulating member interposed therebetween . 6. The inverter capacitor connection structure according to claim 5 , wherein the insulating member is formed by laminating a plurality of thin plate insulators . The first conductive member and the second conductive member are provided corresponding to both the positive electrode terminal and the negative electrode terminal of each of the inverter and the capacitor. A capacitor connection structure for an inverter according to any one of claims 1 to 6. The second conductive members, both between the positive electrode terminals and between the negative electrode terminals, are arranged in parallel with a gap therebetween, and face each other with an insulating member interposed therebetween. The inverter capacitor connection structure according to claim 7. Claims wherein said first conductive member to each other both between the positive inter-electrode side of the electrode terminal and the negative electrode side of the electrode terminals arranged in parallel at a gap, characterized in that are opposed to each other via the insulating member capacitor connection structure of an inverter according to 7. In an inverter system composed of an inverter, a capacitor and a battery,
A first conductive member having one end connected to the electrode terminal of the capacitor and the other end connected to the electrode terminal of the inverter;
The first conductive member is arranged in parallel with a gap, and one end is composed of a second conductive member electrically connected to the one end of the first conductive member,
While the other end of the second conductive member is connected to the battery by a power line,
The capacitor connecting structure for an inverter, wherein the one ends of the first and second conductive members are respectively hinge-coupled and electrically connected to a plurality of connection members hinge-coupled to each other .

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