JP2000102266A - Bus electrode plate for inverter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bus electrode plate for inverters wherein current can be inputted in balance, wiring inductance is canceled out, and bracket fixing member are omitted. SOLUTION: A positive pole connecting section 32 is T-shaped, with its lower end connected with the fringe of a lower positive electrode plate 30, and both the left-and right-side ends 32L and 32R of the T are connected with two current input sections (electrode terminals 34 and 34') of a semiconductor module Q1, respectively. The fringe of the upper negative electrode plate 31 of a bus electrode plate 24 is provided with a negative pole connecting section 33 to be connected with a semiconductor module Q2, and the negative pole connecting section 33 and the positive pole connecting section 32 are placed away from each other with their parts close to and facing opposite to each other. The electrode terminals 34 and 34' are formed of a block body of conductive metal, and placed on the drain electrode 35 (base board) of the semiconductor module Q1 in upright position, to support the body of the bus electrode plate 24 from beneath and electrically connect the lower positive electrode plate 30 with the drain electrode 35 of the semiconductor module Q1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a bus electrode plate used in an inverter circuit for driving an electric motor in an industrial vehicle or the like.

[0002]

2. Description of the Related Art Conventionally, an inverter circuit incorporating a semiconductor module has been used for driving a motor in a vehicle driven by an electric motor such as a battery or a forklift.

FIG. 4 is a circuit diagram showing an example of an inverter circuit using the above-described semiconductor module. In FIG.
Equivalent to one.

This inverter circuit includes an upper arm group (Q1, Q3, Q5) and a lower arm group (Q
2, Q4, Q6).
A control signal from a drive circuit (not shown) is input to the gate electrode of each switching element (semiconductor module) at a predetermined timing, and the switching control of turn-on and turn-off is performed. This is a circuit for converting power into AC power for controlling the rotation of the three-phase motor M. When the inverter circuit having such a configuration is used in an electric motor driven vehicle such as the above-described battery forklift, the switching frequency is generally about several tens kHz.

When the semiconductor module in the inverter circuit described above is actually operated at the above switching frequency, it is unavoidable that a large inductance is generated in the circuit wiring inside the semiconductor module or in the connection wiring to the outside. Due to the influence, when the switching element is turned off, a considerable loss of switching power (hereinafter referred to as switching loss) occurs,
On the other hand, when the switching element is turned off, a considerably high surge voltage is generated, which causes electrical damage to the internal circuit.

Here, the switching loss is a power loss that occurs internally when a device having a control electrode, such as the above-mentioned semiconductor module, performs switching, and usually includes a large number (4 to 6) in an inverter circuit. (Approximately one) semiconductor module is used, so that the switching losses generated in these modules are enormous. This large loss has a great effect on driving and operation of an electric vehicle and the like, and the power of the loss is changed to heat generation, which causes heat damage to the semiconductor module.

Conventionally, for the purpose of reducing the switching loss and the surge voltage, two main current electrode wirings (for example, a source electrode wiring and a source electrode wiring in the case of a MOSFET) for inputting / outputting a main current to / from a semiconductor module. Drain electrode wiring) is formed in a flat plate shape, and these are arranged in parallel and close to each other and opposed to each other, and a configuration is adopted in which the main currents flow in opposite directions in the opposed arrangement portion. The main current electrode wiring having such a configuration will be referred to as a bus electrode plate. By adopting such a bus electrode plate, an electromagnetic effect of canceling out (cancelling) the wiring inductance is generated in the opposed arrangement portion by a mutual induction action, and by utilizing this, the wiring inductance is reduced, and furthermore, the wiring effect is reduced. Switching loss and surge voltage were reduced.

In addition, industrial vehicles such as battery and forklift trucks require two inverters for traveling and cargo handling. In recent years, for example, FIG. 5 (FIG. 5 (a) is a plan view, FIG. 2) has proposed a dual inverter circuit 1 having a configuration in which two inverter circuits are juxtaposed as shown in FIG. The dual inverter circuit 1 includes a traveling inverter circuit 2 having semiconductor modules Q1 to Q6, and a semiconductor module Q1 'to Q1.
6 ′, and a bus electrode plate 4 and a power supply capacitor C (in FIG. 5, a configuration in which a plurality of electrolytic capacitors 8 are connected in parallel corresponds to the power supply capacitor C). By sharing a few modules with a single module, it is possible to reduce the volume and weight,
Cost reduction has been achieved.

In FIG. 1, the bus electrode plate 4 is
It has a sandwich structure in which two thin insulating sheets 5 are sandwiched between upper and lower surfaces of two electrode plates 10 and 11. The insulating sheet 5 electrically insulates the two electrode plates 10 and 11, A material that easily transmits the lines of magnetic force is used. A portion extending from the outer edge of each of the electrode plates 10 and 11 corresponds to the main current in each arm pair of the inverter circuits 2 and 3 (module pair of the combination of Q1 and Q2, Q3 and Q4, and Q5 and Q6 in FIG. 4). Connected to the electrode for
A plurality of electrolytic capacitors 8 (corresponding to the power supply capacitors C in FIG. 4) are arranged in tandem on a bracket fixing member 9 for supporting and fixing the bus bar electrode plate 4 from below. Further, the lower electrode plate 10 is connected to a positive terminal of the electrolytic capacitor 8, and the upper electrode plate 11 is connected to a negative terminal of the electrolytic capacitor 8.

The power supply E shown in FIG. 4 has a positive electrode connected to the connection terminal 10a of the lower electrode plate 10, and a negative electrode connected to the connection terminal 11a of the upper electrode plate 11. Although not shown in FIG. 5, each arm pair has one drain electrode and the other source electrode connected to each other, and the connection point is connected to the motor M as shown in FIG. .

In the bus bar electrode plate 4 configured as described above, the two electrode plates 10 and 11 are arranged in parallel and close proximity to each other, and the currents flowing therethrough have a directional relationship between input and output. A reduction in wiring inductance can be expected over the entire bus electrode plate 4 due to the above-described mutual induction action.

[0012]

FIG. 6 shows an arbitrary arm pair (for example, an arm comprising a pair of semiconductor modules Q1 and Q2) in the conventional bus electrode plate 4 in the dual inverter circuit shown in FIG. It is a figure which expands and shows the connection part with (pair), FIG. (A) is a top view, FIG. (B) is a side view. For simplicity, the wiring between the semiconductor modules Q1 and Q2 is not shown.

As shown in FIG. 6A, the outer edge of the lower positive electrode plate 10 of the bus electrode plate 4 has a shape extending straight in the vertical direction in the drawing (the overall shape is substantially rectangular). Most of the current Ii flowing through the electrode plate 10 flows straight along the outer edge of the electrode plate 10 due to the skin effect.

Here, inside the semiconductor module Q1, a plurality of semiconductor chips (not shown) are juxtaposed in the vertical direction in the figure, and a lower electrode is provided in order to uniformly input a current to the plurality of semiconductor chips. Current input portions 12, 12 '(connection portions to the semiconductor module Q1) are provided at two locations on the outer edge of the plate 10. That is, the plurality of current input units 1
Both 2 and 12 ′ and the row of juxtaposed semiconductor chips are installed in parallel with the outer edge of the lower positive electrode plate 10. With such a configuration, the current input unit 1 that is inevitably positioned well in the current input direction (from the bottom to the top in the drawing)
There is a tendency that current input tends to concentrate on 2 ′, and this bias leads to deterioration of current balance between semiconductor chips, leading to electrical damage.

On the outer edge of the upper negative electrode plate 11 of the bus electrode plate 4, a current output portion 13 (connecting portion to the semiconductor module Q2) extending in a direction orthogonal to the outer edge of the lower positive electrode plate 10 is provided. The current Io flows through the current output unit 13 in the horizontal direction in FIG. That is, the bus bar electrode plate 4
In the connection portion between the semiconductor module Q1 and the semiconductor module Q2, the current Ii flowing through the lower positive electrode plate 10 and the current Io flowing through the upper negative electrode plate 11 are orthogonal to each other. However, there is a problem that a factor that induces a surge voltage or switching loss is provided correspondingly.

Further, the bracket fixing member 9 shown in FIG. 5B supports the bus electrode plate 4 from below, and fixes the plurality of electrolytic capacitors 8 (power supply capacitors C) in tandem below the bus electrode plate 4. However, since the bracket fixing member 9 has conventionally caused a large weight, a large volume, and a high cost of the entire dual inverter circuit 1, the bracket fixing member 9 has to be deleted or omitted. Was desired.

Accordingly, an object of the present invention is to enable a well-balanced input of current to two current input portions of each semiconductor module from one electrode plate constituting a bus electrode plate.

Another object of the present invention is to provide a wiring inductance canceling effect by a mutual induction action even at a connection portion between a bus electrode plate and a semiconductor module pair.

Still another object of the present invention is to omit a conventional bracket fixing member to enable stable connection and fixing of an electrolytic capacitor.

[0020]

The present invention mainly relates to a MOSF.
The present invention solves the problem of an inverter circuit using a semiconductor module made of ET, but is not limited to this, and can be applied to an inverter circuit using another semiconductor module such as a bipolar transistor having a similar problem. is there. Since the names of the electrodes are different depending on the type of the semiconductor module, the “main current input electrode”, “main current output electrode”,
The term "control electrode" is used. For example, MOSFE
In the case of T, the drain electrode corresponds to the main current input electrode, the source electrode corresponds to the main current output electrode, and the gate electrode corresponds to the control electrode.

First, in the first invention, in an inverter bus electrode plate for inputting / outputting a current to / from a semiconductor module in an inverter circuit, two electrode plates respectively functioning as a positive electrode and a negative electrode are vertically opposed to each other. And a bus bar electrode plate main body which is disposed at a distance from one another, and is provided on one outer edge of the two electrode plates, and is formed to have the same length from the center position to two main current input portions of the semiconductor module. And a connecting portion.

With this configuration, it is possible to input a uniform current from the outer edge of the bus electrode body to two main current input portions of the semiconductor module, thereby preventing electrical damage to the semiconductor chip.

[0023] The connection part is provided in the semiconductor module.
A direct connection plate for directly connecting the main current input portions at the shortest position and a connection plate connected from the center position of the direct connection plate to the outer edge of the one electrode plate can be formed in a T-shape. With such a shape, it is possible to more reliably input a uniform current to the two main current input portions of the semiconductor module.

The direct connection plate in the T-shaped connection portion may have a shape in which contact surfaces with the two main current input portions are separated in parallel with the connection plate. By adopting such a shape, the connection plate can be formed shorter while securing the parallel separation between the direct connection plate and the outer edge of the bus bar electrode plate main body, and the width of the direct connection plate can be increased by that much, so that a large current can be obtained. Also at the input, the heat generation of the connection part can be reduced.

According to a second aspect of the present invention, in an inverter bus electrode plate for inputting / outputting a current to / from a semiconductor module in an inverter circuit, two electrode plates which respectively function as a positive electrode and a negative electrode are vertically opposed to and separated from each other. The electrode plate main body arranged, the positive and negative electrode plates have portions that are spaced apart from each other at the same position on the outer edge of the electrode plate, and each of the positive electrode connecting portions is connected to the semiconductor module; And a negative electrode connecting portion.

With such a configuration, the effect of canceling the wiring inductance due to the mutual induction can be exerted even between the positive terminal and the negative terminal connected to each semiconductor module pair. , Surge voltage and switching loss are reduced.

According to a third aspect of the present invention, in an inverter bus electrode plate for inputting / outputting a current to / from a semiconductor module in two juxtaposed inverter circuits, two electrode plates which respectively function as a positive electrode and a negative electrode are vertically connected to each other. An electrode plate main body that can be fixedly connected to a power supply capacitor on an upper electrode plate thereof, and a conductive metal block body, which supports the electrode plate main body from below and the semiconductor module. And an electrode terminal for making an electrical connection with the main current electrode.

With this configuration, a bracket for supporting the lower part of the electrode plate body and fixing the power supply capacitor, which is required in the conventional dual inverter circuit, becomes unnecessary. As a result, the entire dual inverter circuit becomes unnecessary. Simplification and weight reduction can be realized.

A fourth aspect of the present invention is used to electrically connect each semiconductor module constituting each of the first and second arms in the inverter circuit for driving the electric motor to a power supply capacitor, A first electrode plate for connecting one terminal and the semiconductor module for the first arm is on an upper side, and a first electrode plate for connecting the other terminal of the power supply capacitor and the semiconductor module for the second arm is on the upper side. So that the first electrode plate is on the lower side.
And an inverter bus electrode plate having a configuration in which a second electrode plate and a second electrode plate are vertically opposed to each other and spaced apart from each other, wherein a first connection, which is a connection portion of the first electrode plate with the first arm semiconductor module, is provided. And a second connection part, which is a connection part of the second electrode plate with the second arm semiconductor module, is disposed close to each other so as to partially oppose each other, and the first and second parts are connected to each other. At least one of the connection portions has a shape that regulates a current path so that the directions of currents flowing through the opposed portions are opposite to each other.

With this configuration, the wiring inductance can be offset by the mutual induction even at the connection portion between each electrode plate and the semiconductor module. As a result, surge voltage and switching loss are reduced. Reduced. The shape for regulating the current path as described above may be provided in either of the first and second connection portions, or may be provided in both.

[0031]

Embodiments of the present invention will be described below with reference to the drawings. In the following, an inverter circuit using a MOSFET as a semiconductor module will be described as an example. However, the present invention is not limited to this, and the present invention can be applied to a semiconductor module using another switching element such as a bipolar transistor or a thyristor having a similar problem. Is as described above.

FIG. 1 shows an arbitrary one of the bus electrodes 24 for a dual inverter according to the first embodiment of the present invention.
Arm pairs (for example, semiconductor modules Q1, Q2
(A) is a plan view, and (b) is a side view.
FIG. 1 corresponds to FIG. 6 showing a conventional configuration,
It is assumed that the basic configuration of the entire dual inverter circuit except this part is the same as that shown in FIG. As in FIG. 6, for simplicity, the semiconductor modules Q1, Q2
The wiring between them is not shown.

In FIG. 1, the main body of the bus electrode plate 24 has a sandwich structure in which one thin insulating sheet 25 is sandwiched between two electrode plates, a lower positive electrode plate 30 and an upper negative electrode plate 31. The common power supply capacitors (the plurality of electrolytic capacitors 8 shown in FIG. 5) of the two inverter circuits and the respective semiconductor modules are horizontally arranged so as to be electrically connected. A portion extending from an outer edge of each of the electrode plates 30 and 31 serves as a positive electrode connection portion 32 and a negative electrode connection portion 33, and each arm pair (FIG. 1 shows only an arm pair including semiconductor modules Q1 and Q2 as an example). Are connected to the main current electrodes (drain electrode, source electrode). The plurality of electrolytic capacitors 8 are connected to the upper negative electrode plate 3.
1, the positive terminal of each electrolytic capacitor 8 is connected to the lower positive electrode plate 30, and the negative terminal is connected to the upper negative electrode plate 31. It is necessary that the electrolytic capacitor 8 body and the upper negative electrode plate 31 be electrically insulated from each other. As a means for this, for example, an insulating sheet may be interposed between them. .

Here, the shape of the positive electrode connecting portion 32 of the lower positive electrode plate 30 is a T-shape extending by connecting the lower end to the outer edge of the bus electrode plate 24 as shown in FIG. The T-shaped lateral left and right ends 32L and 32R are connected to the two electrode terminals 34 and 34 ', respectively, of the semiconductor module Q1. The electrode terminals 34 and 34 ′ are formed of a conductive metal block, and are provided upright on a drain electrode (conductive base substrate) 35 of the semiconductor module Q 1. Then, the electrode terminals 34,
Reference numeral 34 'supports the main body of the bus electrode plate 24 from below, and electrically connects the lower positive electrode plate 30 and the drain electrode 35. Here, the above-mentioned block body is desirably a substantially rectangular parallelepiped having a sufficient height, width, and depth, respectively.
Alternatively, it means a structure having a structure obtained by combining these substantially rectangular parallelepipeds, and has a strength sufficient to support the bus bar electrode plate 24 main body and a plurality of electrolytic capacitors 8 thereon.

The semiconductor module used in the present embodiment is generally called a non-insulated type, that is, it has a conductive base substrate on which each semiconductor chip, each electrode and the like are mounted. When the base substrate is connected to the drain region of the semiconductor chip, a drain electrode 35 is formed.
It functions as. Therefore, the electrode terminal 3
4, 34 'are erected on a drain electrode (base substrate) 35 which is a structurally solid base.

The shape of the negative electrode connecting portion 33 provided on the other upper negative electrode plate 31 is the same as that of the conventional negative electrode connecting portion, and the negative electrode connecting portion 33 is provided at substantially the same width as the position corresponding to the positive electrode connecting portion 32.

The connection portions 32, 33 and the electrode terminals 34, 34 'are firmly fixedly connected to the main current electrodes (drain electrode 35, source electrode 37) of the semiconductor module by, for example, screws 36. .

Although the wiring between the semiconductor modules Q1 and Q2 is not shown, the drain electrode (base substrate) of the semiconductor module Q2 passes between the source electrode 41 of the semiconductor module Q1 and the two electrode terminals 34 and 34 '. ) 4
2, and the wiring is further connected to a three-phase motor to be driven by each inverter circuit (see FIG. 4).

Next, the bus bar electrode plate 24 having the above configuration
The main operation of will be described. First, in FIG. 1A, it is assumed that, for example, the semiconductor module Q1 on the upper arm side and any one of the semiconductor modules on the lower arm side are turned on. I do.

In this case, first, the current Ii input to the semiconductor module Q1 is substantially the same as in the case of FIG.
It flows along the outer edge of the lower positive electrode plate 30 (in the vertical direction in the figure). However, at the time when the current Ii is input from the outer edge to the two electrode terminals 34 and 34 'via the T-shaped positive electrode connecting portion 32, the left and right ends 32L and 32R (from the lower end of the installation of the positive electrode connecting portion 32) Since the energization distances to the electrode terminals 34 and 34 ') are equal, the current Ii is equally divided (divided into two) into the left and right ends 32L and 32R and input. Then, as shown in FIG.
The current Ii is supplied in a well-balanced manner to a plurality of internal semiconductor chips (not shown) via the electrode terminals 34 and 34 'and the drain electrode 35 of the semiconductor module Q1.

Thereafter, the current output from the source electrode 41 of the semiconductor module Q1 passes through a coil in the motor M (see FIG. 4) and passes through the lower arm-side semiconductor module in the ON state (here, the description is simplified. To the drain electrode 42 of the semiconductor module Q2) and output from the source electrode 37 through the internal semiconductor chip. As shown in FIG. 1, the output current Io flows through the negative electrode connecting portion 33 in the shortest distance in a direction parallel to its longitudinal direction (horizontal direction in the figure), and the upper negative electrode plate 31
Flows to the outer edge of.

As described above, the input current Ii and the output current Io
The positive electrode connection part 32 and the negative electrode connection part 33 through which
Since the positive electrode connecting portion 32 is installed at the same position on the outer edge of each of the upper and lower electrode plates 30 and 31 and has the T-shaped shape as described above, at least the lower end installing portions of both the connecting portions 32 and 33 are provided. Indicate that the current flowing directions of the flowing currents Ii and Io are opposite to each other, and
3 are disposed facing each other in a state of being separated from each other via a thin insulating sheet 25 similarly to the main body of the bus bar electrode plate 24, the wiring inductance canceling effect due to the mutual induction is exerted also in this portion, and as a result, the inverter circuit The surge voltage and switching loss in the whole can be further reduced.

The inverter circuit shown in FIG. 4 constitutes a bridge circuit for driving the motor M, and turns on and off each semiconductor module functioning as an upper arm and a lower arm thereof alternately. In principle, the upper and lower arm pairs connected in series with each other (for example, Q1 and Q1 in FIG. 4)
2, Q3 and Q4, Q5 and Q6), that is, switching control is performed so that currents Ii and Io do not simultaneously flow in the upper and lower arm pairs arranged close to each other. However, as described above, the switching frequency is relatively high, such as about several tens of kHz, and the current flow and the surrounding magnetic field generated thereby have a temporal phase difference angle. , 33 in the long term, the currents Ii and Io flowing therethrough are influenced by each other's magnetic field, and as a result, the effect of canceling the wiring inductance by the mutual induction action is exhibited.

Both connecting portions 3 for exhibiting the above effects
The shapes of 2 and 33 are not limited to those shown in FIG. 1, and various shapes that can regulate current paths so that the directions of currents Ii and Io flowing in them are opposite to each other can be adopted. Yes, at least one of the connection portions 32 and 33 only needs to have such a shape. For example, FIGS. 2 and 3
Shows another example of the shape applied to the positive electrode connecting portion, and a similar effect can be obtained with such a shape.

That is, the positive electrode connecting portion 38 shown in FIG.
Has a T-shape in a plan view thereof (FIG. 2A) substantially similar to the positive electrode connecting portion 32 of the first embodiment, but has left and right ends 38L and 38R in front view (FIG. 2
As shown in (b)), it is bent in an L-shape toward the drain electrode (base substrate) 35 of the semiconductor module below, and the height of the electrode terminals 34 and 34 'connected thereto is reduced by that amount. It is to become. With this configuration, the left and right ends 38L and 38R and the lower positive electrode plate 3
Since the T-shaped body can be shortened and the width W of the left and right end portions 38L, 38R can be made large after securing a spatial insulation distance with the main body, the large current can be applied. Heat generation can be reduced.

The positive electrode connecting portion 39 shown in FIG. 3 has a substantially rectangular shape. By forming the positive electrode connecting portion 39 in this way, it is possible to ensure that the current is divided and supplied between two adjacent positive electrode connecting portions. Most heat generation can be suppressed.

Further, the bus electrode plate 24 is firmly supported by the electrode terminals 34, 34 'made of a conductive metal block, and the electrolytic capacitor 8 is mounted on the bus electrode plate 24. Therefore, the bracket fixing member (bracket fixing member 9 in FIG. 5) required in the conventional configuration becomes unnecessary. As a result, the entire dual inverter circuit can be simplified, reduced in weight, and reduced in manufacturing cost.

Although the above embodiment has been described with reference to the bus electrode plate having a configuration in which the positive electrode plate is disposed on the lower side and the negative electrode plate is disposed on the upper side, the polarity relationship of the entire circuit is reversed. Accordingly, the present invention is similarly applicable to a bus electrode plate having a configuration in which the negative electrode plate is disposed on the lower side and the positive electrode plate is disposed on the upper side.

In the above embodiment, a thin insulating sheet is interposed between the two electrode plates. However, it is not always necessary to use such an insulating sheet, and the two electrode plates are opposed to each other with a certain distance therebetween. It is also possible to employ various configurations in which the magnetic field lines can be insulated from each other in a state where they can be transmitted.

[0050]

As described above, according to the present invention, it is possible to input a well-balanced current from the electrode plate to two current input portions of the semiconductor module. Electrical damage to the semiconductor chip is prevented.

Also at the connection portion between the bus electrode plate and the semiconductor module pair, the effect of canceling the wiring inductance by the mutual induction action is exhibited, so that the surge voltage and the switching loss in the entire inverter circuit can be reduced. As a result, the number of semiconductor chips can be reduced because the heat sink can be made smaller, snubberless, or derating can be reduced.As a result, it is possible to improve the reliability of the semiconductor module and, consequently, the inverter circuit and reduce the manufacturing cost. Become.

Furthermore, by making it possible to stably connect and fix the power supply capacitor without the need for the bracket fixing member conventionally required, the entire dual inverter circuit can be simplified, lightened, and the manufacturing cost can be reduced. Become.

[Brief description of the drawings]

FIG. 1 is an enlarged view showing a connection portion with an arbitrary arm pair in a dual inverter bus electrode plate according to a first embodiment of the present invention, FIG.
(B) is a side view.

FIGS. 2A and 2B are diagrams showing a positive electrode connecting portion according to a second embodiment of the present invention, wherein FIG. 2A is a plan view and FIG. 2B is a front view.

FIG. 3 is a plan view of a positive electrode connecting portion according to a third embodiment of the present invention.

FIG. 4 is a circuit diagram illustrating an example of an inverter circuit using a semiconductor module.

5A and 5B are diagrams showing a conventional dual inverter structure, wherein FIG. 5A is a plan view and FIG. 5B is a side view.

FIG. 6 is an enlarged view showing a connection portion with an arbitrary arm pair in the conventional bus electrode plate in the dual inverter circuit shown in FIG. 5, (a) is a plan view, (b)
Is a side view.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Dual inverter circuit 2, 3 Inverter circuit 4 Bus electrode plate 5 Insulating sheet 8 Electrolytic capacitor 9 Bracket fixing member 10 Lower positive electrode plate 11 Upper negative electrode plate 12, 12 'Current input part (drain electrode terminal) 13 Current output part 24 Bus electrode plate 25 Insulating sheet 28 Electrolytic capacitor 30 Lower positive electrode plate 31 Upper negative electrode plate 32 Positive electrode connection 33 Negative electrode connection 34, 34 'Electrode terminal 35 Drain electrode (base substrate) 36 Screw 37 Source electrode 38 Positive electrode connection Part 39 Positive electrode connection part 41 Source electrode 42 Drain electrode (base substrate) Q1 to Q6, Q1 'to Q6' Switching element (semiconductor module) M Three-phase motor C Power supply capacitor E Power supply Ii Input current Io Output current

Claims (6)

[Claims] 1. An inverter bus electrode plate for inputting / outputting a current to / from a semiconductor module in an inverter circuit, wherein two electrode plates serving as a positive electrode and a negative electrode, respectively, are vertically spaced apart from each other. A bus electrode plate main body, and connection portions provided on one outer edge of the two electrode plates and formed to have the same length from the center position to two main current input portions of the semiconductor module, respectively. A bus electrode plate for an inverter, comprising: 2. A connection plate, wherein the connection portion directly connects two main current input portions of the semiconductor module to the shortest, and a connection plate connected from a center position of the direct connection plate to an outer edge of the one electrode plate. The bus electrode plate for an inverter according to claim 1, wherein the bus electrode plate is formed in a T shape. 3. The direct connection plate in the T-shaped connection portion has a shape in which contact surfaces with the two main current input portions are separated in parallel with the connection plate. 2. The bus electrode plate for an inverter according to 2. 4. An inverter bus electrode plate for inputting / outputting a current to / from a semiconductor module in an inverter circuit, wherein two electrode plates which respectively function as a positive electrode and a negative electrode are spaced apart from each other vertically. An electrode plate main body, and a positive electrode connection portion and a negative electrode connection portion each having a portion which is spaced apart from each other at the same position on the outer edges of the positive electrode plate and the negative electrode plate, each of which is connected to the semiconductor module; A bus electrode plate for an inverter, comprising: 5. An inverter bus electrode plate for inputting / outputting a current to / from a semiconductor module in two juxtaposed inverter circuits, wherein two electrode plates each serving as a positive electrode and a negative electrode are vertically opposed to each other. An electrode plate main body, which is spaced apart from the power supply capacitor and can be fixedly connected to the upper electrode plate thereof, and a conductive metal block body, which supports the electrode plate main body from below and serves for main current of the semiconductor module. An electrode bus terminal plate for an inverter, comprising: an electrode terminal for making an electrical connection with an electrode. 6. A power supply capacitor for electrically connecting each of the semiconductor modules constituting the first and second arms in an inverter circuit for driving an electric motor with one terminal of the power supply capacitor. A first electrode plate for connecting the semiconductor module for the first arm is on the upper side, and a second electrode plate for connecting the other terminal of the power supply capacitor and the semiconductor module for the second arm. A bus bar electrode plate for an inverter having a configuration in which the first and second electrode plates are vertically opposed to each other and are separated from each other so that the lower side of the semiconductor module for the first arm is disposed on the first electrode plate. A first connection part that is a connection part with the second arm plate, and a second connection part that is a connection part with the second arm semiconductor module in the second electrode plate. At least one of the first and second connection portions regulates a current path so that the directions of currents flowing through the opposed portions are opposite to each other. A bus electrode plate for an inverter, having a shape.