Power conversion device

A power conversion device includes element array having a high side arm element and a low side arm element, positive electrode-side conductor electrically connected to the high side arm element, negative electrode-side conductor electrically connected to the low side arm element, output-side conductor electrically connected to the high side arm element and the low side arm element, high side driving signal line that controls the high side arm element, and low side driving signal line that controls the low side arm element, the positive electrode-side conductor and the negative electrode-side conductor extend from the element array toward one side in first direction, the output-side conductor extends from the element array toward the other side opposite to the one side in the first direction, and the high side driving signal line and the low side driving signal line extend from the element array toward a second direction crossing the first direction.

CROSS-REFERENCE TO RELATED APPLICATION

Priority is claimed on Japanese Patent Application No. 2018-047616, filed Mar. 15, 2018, the content of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a power conversion device.

Description of Related Art

In the related art, a semiconductor device that does not require a process of vertically inverting semiconductor elements when the semiconductor elements are disposed is known (for example, see Japanese Unexamined Patent Application, First Publication No. 2012-235081). In the semiconductor device disclosed in Japanese Unexamined Patent Application, First Publication No. 2012-235081, a first semiconductor element and a second semiconductor element are disposed in parallel. In addition, when a thin plate section of a conductor electrically connected to an electrode of the first semiconductor element on an upper surface side is fixed to a thin plate section of a conductor electrically connected to an electrode of a second semiconductor element on a lower surface side, the electrode of the first semiconductor element on the upper surface side is electrically connected to the electrode of the second semiconductor element on the lower surface side.

SUMMARY OF THE INVENTION

Incidentally, in the semiconductor device disclosed in Japanese Unexamined Patent Application, First Publication No. 2012-235081, a positive electrode-side conductor, a negative electrode-side conductor, and an output-side conductor extend from the first semiconductor element and the second semiconductor element toward one side in a first direction. In addition, a control electrode terminal (a driving signal line) configured to drive the first semiconductor element and a control electrode terminal (a driving signal line) configured to drive a second semiconductor element extend from the first semiconductor element and the second semiconductor element toward the other side opposite to one side in the first direction.

That is, in the semiconductor device disclosed in Japanese Unexamined Patent Application, First Publication No. 2012-235081, a direction crossing the first direction is not used as the direction in which the positive electrode-side conductor, the negative electrode-side conductor, the output-side conductor, and the control electrode terminal (the driving signal line) extend.

For this reason, in the semiconductor device disclosed in Japanese Unexamined Patent Application, First Publication No. 2012-235081, parts electrically connected to the positive electrode-side conductor and the negative electrode-side conductor, parts electrically connected to the output-side conductor, and parts electrically connected to the control electrode terminal (the driving signal line) are densely packed.

As a result, in the semiconductor device disclosed in Japanese Unexamined Patent Application, First Publication No. 2012-235081, a process of disposing these parts is complicated. Specifically, a process of wiring and connecting the positive electrode-side conductor, the negative electrode-side conductor, the output-side conductor, and the control electrode terminal (the driving signal line) to the plurality of above-mentioned parts is complicated.

When the complicate wiring connection is realized, the wiring connection members gets lengthened. In addition, when the complicate wiring connection is realized, a space-saving property is decreased.

An aspect of the present invention is directed to providing a power conversion device capable of simplifying disposition of parts wired and connected to a positive electrode-side conductor, a negative electrode-side conductor, an output-side conductor and driving signal lines of elements, and facilitating wiring and connection of the positive electrode-side conductor, the negative electrode-side conductor, the output-side conductor and the driving signal lines of the elements to the parts.

(1) A power conversion device according to an aspect of the present invention includes an element array having a high side arm element and a low side arm element, a positive electrode-side conductor electrically connected to the high side arm element, a negative electrode-side conductor electrically connected to the low side arm element, an output-side conductor electrically connected to the high side arm element and the low side arm element, a high side driving signal line configured to transmit a control signal to control the high side arm element to drive the high side arm element, and a low side driving signal line configured to transmit a control signal to control the low side arm element to drive the low side arm element, wherein the positive electrode-side conductor and the negative electrode-side conductor extend from the element array toward one side in a first direction, the output-side conductor extends from the element array toward the other side opposite to the one side in the first direction, and the high side driving signal line and the low side driving signal line extend from the element array toward a second direction crossing the first direction.

(2) The power conversion device according to the aspect (1) may further include a first substrate and a second substrate, wherein the first substrate may include a first conductive layer disposed to face an electrode of an one-side surface of the high side arm element; a second conductive layer disposed to face an electrode of an one-side surface of the low side arm element; a first electric insulating layer connected to the first conductive layer and the second conductive layer; a third conductive layer disposed at a side opposite to the first conductive layer and the second conductive layer with the first electric insulating layer interposed therebetween; and a second electric insulating layer disposed at a side opposite to the first electric insulating layer with the third conductive layer interposed therebetween, the second substrate may include a fourth conductive layer disposed to face an electrode of an other-side surface of the high side arm element; a fifth conductive layer disposed to face an electrode of an other-side surface of the low side arm element; and a third electric insulating layer connected to the fourth conductive layer and the fifth conductive layer, and one of the positive electrode-side conductor and the negative electrode-side conductor may be connected to any one of the first conductive layer and the second conductive layer and extends toward the one side toward the first direction, the other one of the positive electrode-side conductor and the negative electrode-side conductor may be connected to the third conductive layer and extends toward the one side in the first direction, and the output-side conductor may be connected to the second conductive layer and extends toward the other side in the first direction.

(3) In the power conversion device according to the aspect (2), the fourth conductive layer and the second conductive layer may be electrically connected to each other, and the fifth conductive layer and the third conductive layer may be electrically connected to each other.

(4) In the power conversion device according to the aspect (2) or (3), the first substrate may include a first heat conductive section formed of a conductive material, the first heat conductive section may be disposed at a side opposite to the third conductive layer with the second electric insulating layer interposed therebetween, the second substrate may include a second heat conductive section formed of a conductive material, and the second heat conductive section may be disposed at a side opposite to the fourth conductive layer and the fifth conductive layer with the third electric insulating layer sandwiched therebetween.

(5) A power conversion device according to an aspect of the present invention includes an element array having a high side arm element and a low side arm element; a positive electrode-side conductor electrically connected to the high side arm element; a negative electrode-side conductor electrically connected to the low side arm element; an output-side conductor electrically connected to the high side arm element and the low side arm element; a first substrate; and a second substrate, wherein the first substrate may include a first conductive layer disposed to face an electrode of an one-side surface of the high side arm element; a second conductive layer disposed to face an electrode of an one-side surface of the low side arm element; a first electric insulating layer connected to the first conductive layer and the second conductive layer; a third conductive layer disposed at a side opposite to the first conductive layer and the second conductive layer with the first electric insulating layer interposed therebetween; and a second electric insulating layer disposed at a side opposite to the first electric insulating layer with the third conductive layer interposed therebetween, and the second substrate may include a fourth conductive layer disposed to face an electrode of an other-side surface of the high side arm element; a fifth conductive layer disposed to face an electrode of an other-side surface of the low side arm element; and a third electric insulating layer connected to the fourth conductive layer and the fifth conductive layer, one of the positive electrode-side conductor and the negative electrode-side conductor may be connected to any one of the first conductive layer and the second conductive layer, and the other one of the positive electrode-side conductor and the negative electrode-side conductor may be connected to third conductive layer.

In the power conversion device according to the aspect (1), a direction in which the positive electrode-side conductor and the negative electrode-side conductor extend from the element array, a direction in which the output-side conductor extends from the element array, and a direction in which the high side driving signal line and the low side driving signal line extend from the element array are different from each other.

For this reason, in the power conversion device according to the aspect (1), disposition of parts wired and connected to the positive electrode-side conductor and negative electrode-side conductor, parts wired and connected to the output-side conductor, and parts wired and connected to the high side driving signal line and the low side driving signal line can be simplified, a length of a wiring connection member to these parts can be minimized, and a space-saving property can be improved.

In the power conversion device according to the aspect (2), the first substrate includes the first electric insulating layer and the second electric insulating layer.

For this reason, in the power conversion device according to the aspect (2), a configuration in which the positive electrode-side conductor and the negative electrode-side conductor extend toward one side in the first direction, the output-side conductor extends toward the other side in the first direction, and the high side driving signal line and the low side driving signal line extend toward a second direction crossing the first direction can be realized.

In the power conversion device according to the aspect (3), the fourth conductive layer of the second substrate and the second conductive layer of the first substrate are electrically connected to each other.

For this reason, in the power conversion device according to the aspect (3), a configuration of the element array in which the high side arm element and the low side arm element are electrically connected to each other can be realized.

In the power conversion device according to the aspect (3), the fifth conductive layer of the second substrate and the third conductive layer of the first substrate are electrically connected to each other.

For this reason, in the power conversion device according to the aspect (3), the negative electrode-side conductor can extend in the same direction as the positive electrode-side conductor with no interference with the high side arm element and the low side arm element.

In the power conversion device according to the aspect (4), the first substrate includes the first heat conductive section formed of the conductive material, and the second substrate includes the second heat conductive section formed of the conductive material.

For this reason, in the power conversion device according to the aspect (4), cooling performance of the high side arm element and the low side arm element can be improved in comparison with the case in which the first heat conductive section and the second heat conductive section are not provided.

In the power conversion device according to the aspect (5), the first substrate includes the first electric insulating layer and the second electric insulating layer.

For this reason, in the power conversion device according to the aspect (5), a configuration in which the positive electrode-side conductor and the negative electrode-side conductor extend toward one side in the first direction, the output-side conductor extends toward the other side in the first direction, and the high side driving signal line and the low side driving signal line extend toward the second direction crossing the first direction can be realized.

When the configuration is realized, in the power conversion device according to the aspect (5), disposition of parts wired and connected to the positive electrode-side conductor and the negative electrode-side conductor, parts wired and connected to the output-side conductor, and parts wired and connected to the high side driving signal line and the low side driving signal line can be simplified, a length of a wiring connection member to these parts can be minimized, and a space-reducing property can be improved.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, embodiments of a power conversion device of the present invention will be described with reference to the accompanying drawings.

First Embodiment

FIG. 1AandFIG. 1Bare views showing an example of a power conversion device1of a first embodiment. Specifically,FIG. 1Ais a plan view of the power conversion device1of the first embodiment when a substrate SB and spacers SPUH and SPUL are seen therethrough.FIG. 1Bis a front view of the power conversion device1of the first embodiment.FIG. 2is a view showing only a high side arm element UH and a low side arm element UL, which are extracted, inFIG. 1B.FIG. 3is a view showing only the substrate SB, which is extracted, inFIG. 1B.FIG. 4is a perspective view of a substrate SA shown inFIG. 1AandFIG. 1B.FIG. 5is a front view of the substrate SA and a radiation section WJ shown inFIG. 1AandFIG. 1B.

In the example shown inFIG. 1AtoFIG. 5, the power conversion device1includes the high side arm element UH, a flywheel diode DUH connected to the high side arm element UH in reverse in parallel, the low side arm element UL, a flywheel diode DUL connected to the low side arm element UL in reverse parallel, the substrate SA, the substrate SB, a high side driving signal line SH, a low side driving signal line SL, the spacer SPUH, the spacer SPUL, a connecting section CO, a connecting section CN, a positive electrode-side conductor (a P bus bar) PI, a negative electrode-side conductor (an N bus bar) NI, an output-side conductor (an output bus bar)51, and the radiation section WJ.

The high side arm element UH and the low side arm element UL are switching elements such as an insulated gate bipolar transistor (IGBT), a metal oxide semiconductor field effect transistor (MOSFET), or the like.

The high side arm element UH of one phase extent may be constituted by a plurality of switching elements that are connected in parallel. Similarly, the low side arm element UL of one phase extent may be constituted by a plurality of switching elements that are connected in parallel.

As shown inFIG. 2, an electrode UHA1is disposed on a surface UHA of the high side arm element UH on one side (a lower side inFIG. 2). An electrode UHB1and a gate electrode (not shown) to which a driving signal is input are disposed on a surface UHB of the high side arm element UH on the other side (an upper side inFIG. 2). An electrode ULA1is disposed on a surface ULA of the low side arm element UL on one side (the lower side inFIG. 2). An electrode ULB1and a gate electrode (not shown) to which a driving signal is input are disposed on a surface ULB of the low side arm element UL on the other side (the upper side inFIG. 2). An element array UHL is constituted by the high side arm element UH and the low side arm element UL. That is, the element array UHL has the high side arm element UH and the low side arm element UL.

In the example shown inFIG. 1AtoFIG. 5, the high side arm element UH and the low side arm element UL that constitute the element array UHL are arranged in a leftward/rightward direction inFIG. 1A(i.e., a direction in which the positive electrode-side conductor PI, the negative electrode-side conductor NI and the output-side conductor51extend).

As shown inFIG. 3, the substrate SB includes a conductive layer SB1disposed to face the electrode UHB1of the high side arm element UH, a conductive layer SB2disposed to face the electrode ULB1of the low side arm element UL, an electric insulating layer SB3connected to the conductive layer SB1and the conductive layer SB2, and a heat conductive section SB4disposed on a side opposite to the conductive layer SB1and the conductive layer SB2with the electric insulating layer SB3interposed therebetween. The heat conductive section SB4is formed of a conductive material.

As shown inFIG. 1B, the spacer SPUH is disposed between the electrode UHB1of the high side arm element UH and the conductive layer SB1of the substrate SB. The spacer SPUL is disposed between the electrode ULB1of the low side arm element UL and the conductive layer SB2of the substrate SB.

In the example shown inFIG. 1AtoFIG. 5, a gate electrode (not shown) of the high side arm element UH is electrically connected to the high side driving signal line SH via, for example, a bonding wire (not shown) or the like. The electrode UHB1of the high side arm element UH is electrically connected to the conductive layer SB1of the substrate SB via the spacer SPUH.

A gate electrode (not shown) of the low side arm element UL is electrically connected to the low side driving signal line SL via, for example, a bonding wire (not shown) or the like. The electrode ULB1of the low side arm element UL is electrically connected to the conductive layer SB2of the substrate SB via the spacer SPUL.

The high side driving signal line SH and the low side driving signal line SL extend upward from the element array UHL in an upward/downward direction inFIG. 1A(i.e., a direction crossing a leftward/rightward direction), and are wired and connected to a gate drive unit29(G/D VCU ECU) (seeFIG. 10).

That is, the high side driving signal line SH transmits a control signal that controls to drive the high side arm element UH. The low side driving signal line SL transmits a control signal that controls to drive the low side arm element UL.

As shown inFIG. 4andFIG. 5, the substrate SA includes a conductive layer SA1, a conductive layer SA2, an electric insulating layer SA3, a conductive layer SA4, an electric insulating layer SA5and a heat conductive section SA6.

The conductive layer SA1is disposed to face the electrode UHA1of the high side arm element UH.

The conductive layer SA2is disposed to face the electrode ULA1of the low side arm element UL.

The electric insulating layer SA3is connected to the conductive layer SA1and the conductive layer SA2. The conductive layer SA4is disposed at a side opposite to the conductive layer SA1and the conductive layer SA2with the electric insulating layer SA3interposed therebetween. The electric insulating layer SA5is disposed at a side opposite to the electric insulating layer SA3with the conductive layer SA4interposed therebetween. The heat conductive section SA6formed of a conductive material is disposed at a side opposite to the conductive layer SA4with the electric insulating layer SA5interposed therebetween. The heat conductive section SA6is connected to the radiation section WJ.

In the example shown inFIG. 1AtoFIG. 5, the electrode UHA1of the high side arm element UH is electrically connected to the conductive layer SA1of the substrate SA. The electrode ULA1of the low side arm element UL is electrically connected to the conductive layer SA2of the substrate SA.

As shown inFIG. 1A, the positive electrode-side conductor PI is electrically connected to the conductive layer SA1of the substrate SA. That is, the positive electrode-side conductor PI is electrically connected to the electrode UHA1of the high side arm element UH. Specifically, the positive electrode-side conductor PI extends leftward from the element array UHL in a leftward/rightward direction ofFIG. 1Aand is wired and connected to a positive electrode bus bar50p(seeFIG. 10) of a condenser unit23(seeFIG. 10).

As shown inFIG. 1AandFIG. 1B, the conductive layer SB1of the substrate SB electrically connected to the electrode UHB1of the high side arm element UH is electrically connected to the conductive layer SA2of the substrate SA via the connecting section CO. The output-side conductor51is electrically connected to the conductive layer SA2of the substrate SA. In addition, the electrode ULA1of the low side arm element UL is electrically connected to the conductive layer SA2of the substrate SA. That is, the output-side conductor51is electrically connected to the electrode UHB1of the high side arm element UH and the electrode ULA1of the low side arm element UL. Specifically, the output-side conductor51extends rightward from the element array UHL in the leftward/rightward direction ofFIG. 1Aand is wired and connected to a 3-phase connector1b(seeFIG. 10) connected to a motor12(seeFIG. 10).

In the example shown inFIG. 1AandFIG. 1B, current flowing from the positive electrode-side conductor PI to the conductive layer SA1of the substrate SA flows from the electrode UHA1(seeFIG. 2) of the high side arm element UH to the electrode UHB1(seeFIG. 2), then flows from the conductive layer SB1(seeFIG. 3) of the substrate SB to the connecting section CO, and then flows from the conductive layer SA2of the substrate SA to the output-side conductor51.

Current flowing from the output-side conductor51to the conductive layer SA2of the substrate SA flows from the electrode ULA1(seeFIG. 2) of the low side arm element UL to the electrode ULB1(seeFIG. 2), then flows from the conductive layer SB2(seeFIG. 3) of the substrate SB to the connecting section CN, and then flows from the conductive layer SA4of the substrate SA to the negative electrode-side conductor NI.

In another example, it is also possible to exchange between the position of the high side arm element UH and the position of the low side arm element UL (i.e., connect the positive electrode-side conductor PI to the conductive layer SA4) while exchanging between the position of the positive electrode-side conductor PI and the position of the negative electrode-side conductor NI.

As shown inFIG. 1AandFIG. 1B, the conductive layer SB2of the substrate SB electrically connected to the electrode ULB1of the low side arm element UL is electrically connected to the conductive layer SA4of the substrate SA via the connecting section CN. The negative electrode-side conductor NI is electrically connected to the conductive layer SA4of the substrate SA. That is, the negative electrode-side conductor NI is electrically connected to the electrode ULB1of the low side arm element UL. Specifically, the negative electrode-side conductor NI extends leftward from the element array UHL in the leftward/rightward direction ofFIG. 1Aand is wired and connected to a negative electrode bus bar50n(seeFIG. 10) of the condenser unit23(seeFIG. 10).

That is, as shown inFIG. 1BandFIG. 5, the conductive layer SA4electrically connected to the negative electrode-side conductor NI is disposed in the middle of a heat radiation path (a heat radiation path extending from an upper side to a lower side ofFIG. 1BandFIG. 5) spanning from the high side arm element UH and the low side arm element UL to the radiation section WJ and a space-saving property is improved.

In the power conversion device1of the first embodiment, as shown inFIG. 1A, a direction in which the positive electrode-side conductor PI and the negative electrode-side conductor NI extend from the element array UHL (a leftward direction inFIG. 1A), a direction in which the output-side conductor51extends from an element array UL (a rightward direction inFIG. 1A) and a direction in which the high side driving signal line SH and the low side driving signal line SL extend from the element array UHL (an upward direction inFIG. 1A) are different from each other.

For this reason, in the power conversion device1of the first embodiment, disposition of the condenser unit23(seeFIG. 10) wired and connected to the positive electrode-side conductor PI and the negative electrode-side conductor NI, the 3-phase connector1b(seeFIG. 10) wired and connected to the output-side conductor51, and the gate drive unit29(seeFIG. 10) wired and connected to the high side driving signal line SH and the low side driving signal line SL can be simplified, a length of a wiring connection member to these can be minimized, and a space-saving property can be improved.

In addition, in the power conversion device1of the first embodiment, it is possible to minimize the possibility that a complicated bus bar structure configured to wire and connect the positive electrode-side conductor PI and the negative electrode-side conductor NI to the output-side conductor51is required, and it is possible to facilitate wiring connection of the condenser unit23to the positive electrode-side conductor PI and the negative electrode-side conductor NI and wiring connection of the 3-phase connector1bto the output-side conductor51.

In addition, in the power conversion device1of the first embodiment, as shown inFIG. 5, the substrate SA includes the electric insulating layer SA3and the electric insulating layer SA5.

For this reason, in the power conversion device1of the first embodiment, it is possible to realize a configuration in which the positive electrode-side conductor PI and the negative electrode-side conductor NI extend leftward inFIG. 1A, the output-side conductor51extends rightward inFIG. 1A, and the high side driving signal line SH and the low side driving signal line SL extend upward inFIG. 1A.

Specifically, in the power conversion device1of the first embodiment, as shown inFIG. 1AandFIG. 1B, the conductive layer SB1of the substrate SB and the conductive layer SA2of the substrate SA are electrically connected via the connecting section CO. For this reason, in the power conversion device1of the first embodiment, it is possible to realize a configuration of the element array UHL in which the high side arm element UH and the low side arm element UL are electrically connected.

In addition, in the power conversion device1of the first embodiment, the conductive layer SB2of the substrate SB and the conductive layer SA4of the substrate SA are electrically connected via the connecting section CN. For this reason, in the power conversion device1of the first embodiment, the negative electrode-side conductor NI can extend in the same direction as the positive electrode-side conductor PI (in the leftward direction ofFIG. 1A) with no interference with the high side arm element UH and the low side arm element UL.

In the power conversion device1of the first embodiment, as shown inFIG. 5, the substrate SA includes the heat conductive section SA6formed of a conductive material. In addition, as shown inFIG. 1BandFIG. 3, the substrate SB includes the heat conductive section SB4formed of a conductive material.

For this reason, in the power conversion device1of the first embodiment, cooling performance of the high side arm element UH and the low side arm element UL can be improved in comparison with the case in which the heat conductive section SA6and the heat conductive section SB4are not provided.

In other words, in the power conversion device1of the first embodiment, the substrate SA has five layers in the upward/downward direction ofFIG. 5. Specifically, the uppermost layer is the conductive layer SA1and the conductive layer SA2, a second layer from above is the electric insulating layer SA3, a third layer from above is the conductive layer SA4, a fourth layer from above is the electric insulating layer SA5, and the lowermost layer is a heat conductive section SA5.

When the substrate SA is used, in the power conversion device1of the first embodiment, a direction in which the positive electrode-side conductor PI and the negative electrode-side conductor NI extend and a direction in which the output-side conductor51extends are different from each other. As a result, wiring connection of the condenser unit23(seeFIG. 10) with respect to the positive electrode-side conductor PI and the negative electrode-side conductor NI and wiring connection of the 3-phase connector1b(seeFIG. 10) with respect to the output-side conductor51can be performed in a small space.

In addition, the conductive layer SA4electrically connected to the negative electrode-side conductor NI is sandwiched between the high side arm element UH and the low side arm element UL and the radiation section WJ and is disposed on a heat radiation path from the high side arm element UH and the low side arm element UL to the radiation section WJ. For this reason, formation of a circuit in a small space can be performed.

In the power conversion device1of the first embodiment, as shown inFIG. 1A, electrical connection to the positive electrode-side conductor PI and the negative electrode-side conductor NI is performed at a left side of the substrate SA having a rectangular shape, electrical connection to the output-side conductor51is performed at a right side of the substrate SA, and electrical connection to the high side driving signal line SH and the low side driving signal line SL is performed at an upper side of the substrate SA.

For this reason, in the power conversion device1of the first embodiment, it is possible to minimize a possibility of mutual interference between a path of the substrate and the motor, a possibility of containing noise in a driving signal, and a possibility of making it difficult to take a control timing using a high side arm and a low side arm while not being controlled by one substrate as the high side driving signal line and the low side driving signal line extend in different directions.

In the power conversion device1of the first embodiment, wiring connection to the condenser unit23, the 3-phase connector1band the gate drive unit29can be performed at the shortest distance, and wiring connection to the condenser unit23, the 3-phase connector1b, and the gate drive unit29can be performed by a simple structure. That is, in the power conversion device1of the first embodiment, the condenser unit23, the 3-phase connector1b, and the gate drive unit29can be easily disposed around the power conversion device1.

In addition, in the power conversion device1of the first embodiment, as shown inFIG. 5, a right end portion of the conductive layer SA4of the substrate SA protrudes rightward from right end portions of the electric insulating layers SA3and SA5to be exposed.

The exposed right end portion of the conductive layer SA4is used for electrical connection to the connecting section CN.

In addition, the left end portion of the conductive layer SA4of the substrate SA protrudes leftward from left end portions of the electric insulating layers SA3and SA5to be exposed. The exposed left end portion of the conductive layer SA4is used for electrical connection to the negative electrode-side conductor NI.

In the power conversion device1of the first embodiment, as shown inFIG. 5, the substrate SA has the plurality of electric insulating layers SA3and SA5. The conductive layer SA4that constitutes a circuit is assembled between the electric insulating layer SA3and the electric insulating layer SA5. For this reason, as described above, electrical connection to the positive electrode-side conductor PI and the negative electrode-side conductor NI is performed at a left side of the substrate SA having a rectangular shape. In addition, electrical connection to the output-side conductor51is performed at a right side facing the left side of the substrate SA.

Electrical connection to the high side driving signal line SH and the low side driving signal line SL is performed intensively on an upper side, which is neither the left side nor the right side of the substrate SA.

As described above, the positive electrode-side conductor PI and the negative electrode-side conductor NI are wired and connected to the condenser unit23, and the output-side conductor51is wired and connected to the 3-phase connector1b. A circuit substrate that constitutes the gate drive unit29is disposed above or below the substrate SA of the power conversion device1inFIG. 5in a surface perpendicular to the substrates SA and SB of the power conversion device1. As a result, wiring connection from the power conversion device1to the condenser unit23, wiring connection from the power conversion device1to the 3-phase connector1b, and wiring connection from the power conversion device1to the gate drive unit29can be intensively arranged at a short distance.

Second Embodiment

Hereinafter, a second embodiment of the power conversion device1of the present invention will be described.

The power conversion device1of the second embodiment is constituted by the same configuration as the power conversion device1of the above-mentioned first embodiment except the following points. Accordingly, according to the power conversion device1of the second embodiment, the same effect as the power conversion device1of the above-mentioned first embodiment can be exhibited except the following points.

FIG. 6is a view showing an example of the power conversion device1of the second embodiment. Specifically,FIG. 6is a plan view of the power conversion device1of the second embodiment when the substrate SB and the spacers SPUH and SPUL are seen therethrough.FIG. 7AandFIG. 7Bare views showing parts of the substrate SA shown inFIG. 6. Specifically,FIG. 7Ais a plan view of the substrate SA andFIG. 7Bis a front view of the substrate SA.FIG. 8is a view for explaining a current path from the positive electrode-side conductor PI to the output-side conductor51.FIG. 9is a view for explaining a current path from the output-side conductor51to the negative electrode-side conductor NI.

In the power conversion device1of the first embodiment, as shown inFIG. 5, the right end portion of the conductive layer SA4of the substrate SA protrudes rightward from the right end portions of the electric insulating layers SA3and SA5to be exposed. The left end portion of the conductive layer SA4of the substrate SA protrudes leftward from the left end portions of the electric insulating layers SA3and SA5to be exposed.

In the power conversion device1of the second embodiment, as shown inFIG. 7B, the right end portion of the conductive layer SA4of the substrate SA and the right end portions of the electric insulating layers SA3and SA5are disposed at the same position in the leftward/rightward direction ofFIG. 7B. The left end portion of the conductive layer SA4of the substrate SA and the left end portions of the electric insulating layers SA3and SA5are disposed at the same position in the leftward/rightward direction ofFIG. 7B.

In the power conversion device1of the second embodiment, as shown inFIG. 6andFIG. 7A, in order to perform electrical connection to the conductive layer SA4and the connecting section CN, a central section of the electric insulating layer SA3in the leftward/rightward direction ofFIG. 6andFIG. 7Ais cut out, and a central section of the conductive layer SA4in the leftward/rightward direction ofFIG. 6andFIG. 7Ais exposed. In addition, in order to perform electrical connection of the conductive layer SA4and the negative electrode-side conductor NI, a left end portion of the electric insulating layer SA3in the leftward/rightward direction ofFIG. 6andFIG. 7Ais cut out, and a left end portion of the conductive layer SA4in the leftward/rightward direction ofFIG. 6andFIG. 7Ais exposed.

That is, in the power conversion device1of the second embodiment, a width dimension (a dimension in the leftward/rightward direction ofFIG. 7AandFIG. 7B) of the substrate SA is reduced to be smaller than the power conversion device1of the first embodiment.

Accordingly, in the power conversion device1of the second embodiment, the entire width dimension (the dimension in the leftward/rightward direction ofFIG. 6) of the power conversion device1is reduced to be smaller than the power conversion device1of the first embodiment.

As shown inFIG. 8, current flowing from the positive electrode-side conductor PI to the conductive layer SA1of the substrate SA flows from the electrode UHA1(seeFIG. 2) of the high side arm element UH to the electrode UHB1(seeFIG. 2), then flows from the conductive layer SB1of the substrate SB to the connecting section CO, and then flows from the conductive layer SA2of the substrate SA to the output-side conductor51.

As shown inFIG. 9, current flowing from the output-side conductor51to the conductive layer SA2of the substrate SA flows from the electrode ULA1(seeFIG. 2) of the low side arm element UL to the electrode ULB1(seeFIG. 2), then flows from the conductive layer SB2of the substrate SB to the connecting section CN, and then flows from the conductive layer SA4of the substrate SA to the negative electrode-side conductor NI.

InFIG. 8andFIG. 9, illustration of the heat conductive section SB4of the substrate SB is omitted, and an outline of the conductive layer SB1of the substrate SB and an outline of the conductive layer SB2of the substrate SB are shown through the electric insulating layer SB3of the substrate SB.

In another example, it is also possible to change between the position of the high side arm element UH and the position of the low side arm element UL (i.e., connect the positive electrode-side conductor PI to the conductive layer SA4) while changing between the position of the positive electrode-side conductor PI and the position of the negative electrode-side conductor NI.

APPLICATION EXAMPLE

Hereinafter, an application example of the power conversion device1of the present invention will be described with reference to the accompanying drawings.

FIG. 10is a view showing an example of part of a vehicle10to which the power conversion device1of the first or second embodiment is applicable.

When the power conversion device1of the first or second embodiment is applied to the example shown inFIG. 10, seven power conversion devices1of the first or second embodiment are used in the vehicle10shown inFIG. 10.

In the example shown inFIG. 10, the vehicle10includes a battery11(BATT), a first motor12(MOT) for traveling and driving, and a second motor13(GEN) for generation in addition to the power conversion device1.

The battery11includes a battery case and a plurality of battery modules accommodated in the battery case. The battery module includes a plurality of battery cells connected to each other in series. The battery11includes a positive electrode terminal PB and a negative electrode terminal NB, which are connected to a direct current connector1aof the power conversion device1. The positive electrode terminal PB and the negative electrode terminal NB are connected to positive electrode ends and negative electrode ends of the plurality of battery modules, which are connected in series in the battery case.

The first motor12generates a rotational driving force (a power-run operation) using electric power supplied from the battery11. The second motor13generates electric power using a rotational driving force input to the rotary shaft. Here, rotational power of an internal combustion engine is configured to be transmittable to the second motor13. For example, each of the first motor12and the second motor13is an alternating brushless direct current (DC) motor having three phases. The three phases are a U phase, a V phase, and a W phase. Each of the first motor12and the second motor13is an inner rotor type. Each of the first motor12and the second motor13includes a rotator having a permanent magnet for a field system, and a stator having a 3-phase stator winding configured to generate a rotating magnetic field that rotates the rotator. The 3-phase stator winding of the first motor12is connected to the first 3-phase connector1bof the power conversion device1. The 3-phase stator winding of the second motor13is connected to the second 3-phase connector1cof the power conversion device1.

The power conversion device1shown inFIG. 10includes a power module21, a reactor22, the condenser unit23, a resistor24, a first current sensor25, a second current sensor26, a third current sensor27, an electronic control unit28(MOT GEN ECU) and the gate drive unit29.

The power module21includes a first power conversion circuit section31, a second power conversion circuit section32and a third power conversion circuit section33.

When the seven power conversion devices1of the first or second embodiment are used in the vehicle10shown inFIG. 10, the first power conversion circuit section31is constituted by the three power conversion devices1of the first or second embodiment.

Specifically, the first power conversion device1of the first or second embodiment constitutes a U phase of the first power conversion circuit section31. The second power conversion device1of the first or second embodiment constitutes a V phase of the first power conversion circuit section31. The third power conversion device1of the first or second embodiment constitutes a W phase of the first power conversion circuit section31.

The output-side conductor51of the first power conversion circuit section31is connected to the first 3-phase connector1bby combining three phases of a U phase, a V phase, and a W phase. That is, the output-side conductor51of the first power conversion circuit section31is connected to the 3-phase stator winding of the first motor12via the first 3-phase connector1b.

The positive electrode-side conductor PI of the first power conversion circuit section31is connected to the positive electrode terminal PB of the battery11by combining three phases of a U phase, a V phase, and a W phase.

The negative electrode-side conductor NI of the first power conversion circuit section31is connected to the negative electrode terminal NB of the battery11by combining three phases of a U phase, a V phase, and a W phase.

That is, the first power conversion circuit section31converts direct current power input from the battery11via the third power conversion circuit section33into 3-phase alternating current power.

When the seven power conversion devices1of the first or second embodiment are used in the vehicle10shown inFIG. 10, the second power conversion circuit section32is constituted by the three power conversion devices1of the first or second embodiment.

Specifically, the first power conversion device1of the first or second embodiment constitutes a U phase of the second power conversion circuit section32. The second power conversion device1of the first or second embodiment constitutes a V phase of the second power conversion circuit section32. The third power conversion device1of the first or second embodiment constitutes a W phase of the second power conversion circuit section32.

An output-side conductor (an output bus bar)52of the second power conversion circuit section32is connected to the second 3-phase connector1cby combining three phases of a U phase, a V phase, and a W phase. That is, the output-side conductor52of the second power conversion circuit section32is connected to the 3-phase stator winding of the second motor13via the second 3-phase connector1c.

The positive electrode-side conductor PI of the second power conversion circuit section32is connected to the positive electrode terminal PB of the battery11and the positive electrode-side conductor PI of the first power conversion circuit section31by combining three phases of a U phase, a V phase, and a W phase.

The negative electrode-side conductor NI of the second power conversion circuit section32is connected to the negative electrode terminal NB of the battery11and the negative electrode-side conductor NI of the second power conversion circuit section32by combining three phases of a U phase, a V phase, and a W phase

The second power conversion circuit section32converts the 3-phase alternating current power input from the second motor13into direct current power. The direct current power converted by the second power conversion circuit section32can be supplied to at least one of the battery11and the first power conversion circuit section31.

In the example shown inFIG. 10, a U phase high side arm element UH, a V phase high side arm element VH, and a W phase high side arm element WH of the first power conversion circuit section31and a U phase high side arm element UH, a V phase high side arm element VH, and a W phase high side arm element WH of the second power conversion circuit section32are connected to the positive electrode-side conductor PI. The positive electrode-side conductor PI is connected to the positive electrode bus bar50pof the condenser unit23.

A U phase low side arm element UL, a V phase low side arm element VL, and a W phase low side arm element WL of the first power conversion circuit section31and a U phase low side arm element UL, a V phase low side arm element VL, and a W phase low side arm element WL of the second power conversion circuit section32are connected to the negative electrode-side conductor NI. The negative electrode-side conductor NI is connected to the negative electrode bus bar50nof the condenser unit23.

In the example shown inFIG. 10, a connecting point TI between the U phase high side arm element UH of the first power conversion circuit section31and the U phase low side arm element UL, a connecting point TI between the V phase high side arm element VH and the V phase low side arm element VL, and a connecting point TI between the W phase high side arm element WH and the W phase low side arm element WL are connected to the output-side conductor51.

A connecting point TI between the U phase high side arm element UH of the second power conversion circuit section32and the U phase low side arm element UL, a connecting point TI between the V phase high side arm element VH and the V phase low side arm element VL, and a connecting point TI between the W phase high side arm element WH and the W phase low side arm element WL are connected to the output-side conductor52.

In the example shown inFIG. 10, the output-side conductor51of the first power conversion circuit section31is connected to a first input/output terminal Q1. The first input/output terminal Q1is connected to a first 3-phase connector1b. The connecting point TI of each phase of the first power conversion circuit section31is connected to the stator winding of each phase of the first motor12via the output-side conductor51, the first input/output terminal Q1, and the first 3-phase connector1b.

The output-side conductor52of the second power conversion circuit section32is connected to a second input/output terminal Q2. The second input/output terminal Q2is connected to a second 3-phase connector1c. The connecting point TI of each phase of the second power conversion circuit section32is connected to the stator winding of each phase of the second motor13via the output-side conductor52, the second input/output terminal Q2and the second 3-phase connector1c.

In the example shown inFIG. 10, each of the high side arm elements UH, VH and WH and the low side arm elements UL, VL and WL of the first power conversion circuit section31includes a flywheel diode.

Similarly, each of the high side arm elements UH, VH and WH and the low side arm elements UL, VL and WL of the second power conversion circuit section32includes a flywheel diode.

In the example shown inFIG. 10, the gate drive unit29inputs a gate signal to each of the high side arm elements UH, VH and WH and the low side arm elements UL, VL and WL of the first power conversion circuit section31.

Similarly, the gate drive unit29inputs a gate signal to each of the high side arm elements UH, VH and WH and the low side arm elements UL, VL and WL of the second power conversion circuit section32.

The first power conversion circuit section31converts the direct current power input from the battery11via the third power conversion circuit section33into 3-phase alternating current power and supplies U phase current, V phase current, and W phase current, which are alternating current, to the 3-phase stator winding of the first motor12. The second power conversion circuit section32converts the 3-phase alternating current power output from the 3-phase stator winding of the second motor13into direct current power through ON (conduction)/OFF (cutoff) driving of each of the high side arm elements UH, VH and WH and the low side arm elements UL, VL and WL of the second power conversion circuit section32, which are synchronized with rotation of the second motor13.

When the seven power conversion devices1of the first or second embodiment are used in the vehicle10shown inFIG. 10, a high side arm element51and a low side arm element S2of the third power conversion circuit section33are constituted by the high side arm element UH and the low side arm element UL of the one power conversion device1of the first or second embodiment.

The third power conversion circuit section33is a voltage control unit (VCU). The third power conversion circuit section33includes the high side arm element S1and the low side arm element S2, which correspond to one phase extent.

An electrode of the high side arm element S1on a positive electrode side is connected to a positive electrode bus bar PV. The positive electrode bus bar PV is connected to the positive electrode bus bar50pof the condenser unit23. An electrode of the low side arm element S2on a negative electrode side is connected to a negative electrode bus bar NV. The negative electrode bus bar NV is connected to the negative electrode bus bar50nof the condenser unit23. The negative electrode bus bar50nof the condenser unit23is connected to the negative electrode terminal NB of the battery11. An electrode of the high side arm element S1on a negative electrode side is electrically connected to an electrode of the low side arm element S2on a positive electrode side. The high side arm element S1and the low side arm element S2include a flywheel diode.

A bus bar53that constitutes a connecting point between the high side arm element S1and the low side arm element S2of the third power conversion circuit section33is connected to one end of the reactor22. The other end of the reactor22is connected to the positive electrode terminal PB of the battery11. The reactor22includes a coil and a temperature sensor configured to detect a temperature of the coil. The temperature sensor is connected to the electronic control unit28by a signal line.

The third power conversion circuit section33switches ON (conduction)/OFF (cutoff) of the high side arm element S1and the low side arm element S2on the basis of the gate signal input to the gate electrode of the high side arm element S1and the gate electrode of the low side arm element S2from the gate drive unit29.

The third power conversion circuit section33alternately switches between a first state in which the low side arm element S2is set to ON (conduction) and the high side arm element S1is set to OFF (cutoff) and a second state in which the low side arm element S2is set to OFF (cutoff) and the high side arm element S1is set to ON (conduction) during boosting. In the first state, current flows to the positive electrode terminal PB of the battery11, the reactor22, the low side arm element S2, and the negative electrode terminal NB of the battery11in sequence, the reactor22is excited with direct current, and electric energy is stored. In the second state, an actuating voltage (an induction voltage) is generated between both ends of the reactor22such that a variation in magnetic flux due to cutoff of the current flowing through the reactor22is prevented. The induction voltage due to the magnetic energy stored in the reactor22is superimposed on the battery voltage, and a boosted voltage higher than the voltage between the terminals of the battery11is applied between the positive electrode bus bar PV and the negative electrode bus bar NV of the third power conversion circuit section33.

The third power conversion circuit section33alternately switches between the second state and the first state during regeneration. In the second state, current flows to the positive electrode bus bar PV of the third power conversion circuit section33, the high side arm element S1, the reactor22, and the positive electrode terminal PB of the battery11in sequence, the reactor22is excited with direct current, and magnetic energy is stored. In the first state, an actuating voltage (an induction voltage) is generated between both ends of the reactor22such that a variation in magnetic flux due to cut off of the current flowing to the reactor22is prevented. The induction voltage due to the magnetic energy stored in the reactor22is dropped, and the dropped voltage lower than the voltage between the positive electrode bus bar PV and the negative electrode bus bar NV of the third power conversion circuit section33is applied between the positive electrode terminal PB and the negative electrode terminal NB of the battery11.

The condenser unit23includes a first smoothing capacitor41, a second smoothing capacitor42, and a noise filter43.

The first smoothing capacitor41is connected between the positive electrode terminal PB and the negative electrode terminal NB of the battery11. The first smoothing capacitor41smoothes fluctuation in voltage generated according to a switching operation of ON/OFF of the high side arm element S1and the low side arm element S2during regeneration of the third power conversion circuit section33.

The second smoothing capacitor42is connected to between the positive electrode-side conductor PI and the negative electrode-side conductor NI of each of the first power conversion circuit section31and the second power conversion circuit section32and between the positive electrode bus bar PV and the negative electrode bus bar NV of the third power conversion circuit section33. The second smoothing capacitor42is connected to the plurality of positive electrode-side conductors PI and negative electrode-side conductors NI and connected to the positive electrode bus bar PV and the negative electrode bus bar NV via the positive electrode bus bar50pand the negative electrode bus bar50n. The second smoothing capacitor42smoothes fluctuation in voltage generated according to a switching operation of ON/OFF of each of the high side arm elements UH, VH and WH and the low side arm elements UL, VL and WL of the first power conversion circuit section31and the second power conversion circuit section32. The second smoothing capacitor42smoothes fluctuation in voltage generated according to a switching operation of ON/OFF of the high side arm element S1and the low side arm element S2during boosting of the third power conversion circuit section33.

The noise filter43is connected to between the positive electrode-side conductor PI and the negative electrode-side conductor NI of each of the first power conversion circuit section31and the second power conversion circuit section32and between the positive electrode bus bar PV and the negative electrode bus bar NV of the third power conversion circuit section33. The noise filter43includes two condensers that are connected in series. A connecting point of the two condensers is connected to a body ground or the like of the vehicle10.

The resistor24is connected to between the positive electrode-side conductor PI and the negative electrode-side conductor NI of each of the first power conversion circuit section31and the second power conversion circuit section32and between the positive electrode bus bar PV and the negative electrode bus bar NV of the third power conversion circuit section33.

The first current sensor25forms the connecting point TI of each phase of the first power conversion circuit section31, is disposed on the output-side conductor51connected to the first input/output terminal Q1, and detects current of each of the U phase, the V phase, and the W phase. The second current sensor26is disposed on the output-side conductor52connected to the second input/output terminal Q2while forming the connecting point TI of each phase of the second power conversion circuit section32, and detects current of each of the U phase, the V phase, and the W phase. The third current sensor27is disposed on the bus bar53connected to the reactor22while forming the connecting point of the high side arm element S1and the low side arm element S2and detects current flowing through the reactor22.

Each of the first current sensor25, the second current sensor26, and the third current sensor27is connected to the electronic control unit28by a signal line.

The electronic control unit28controls an operation of each of the first motor12and the second motor13. For example, the electronic control unit28is a software function part that serves as a predetermined program executed by a processor such as a central processing unit (CPU) or the like. The software function part is an electronic control unit (ECU) including a processor such as a CPU or the like, a read only memory (ROM) configured to store a program, a random access memory (RAM) configured to temporarily store data, and an electronic circuit such as a timer or the like. Further, at least a part of the electronic control unit28may be an integrated circuit such as large scale integration (LSI) or the like. For example, the electronic control unit28performs feedback control or the like of the current using a current detection value of the first current sensor25and a current target value according to a torque command value with respect to the first motor12and generates a control signal that is input to the gate drive unit29. For example, the electronic control unit28performs feedback control or the like of the current using a current detection value of the second current sensor26and a current target value according to a regeneration command value with respect to the second motor13and generates a control signal that is input to the gate drive unit29. The control signal is a signal showing a timing when each of the high side arm elements UH, VH and WH and the low side arm elements UL, VL and WL of the first power conversion circuit section31and the second power conversion circuit section32is driven to turn ON (conduction)/OFF (cutoff). For example, the control signal is a signal or the like that is pulsewidth-modulated.

The gate drive unit29generates a gate signal for driving each of the high side arm elements UH, VH and WH and the low side arm elements UL, VL and WL of the first power conversion circuit section31and the second power conversion circuit section32to actually turn ON (conduction)/OFF (cutoff) on the basis of the control signal received from the electronic control unit28. For example, the gate drive unit29performs amplification, level shift, and so on, of the control signal and generates a gate signal.

The gate drive unit29generates a gate signal to drive each of the high side arm element S1and the low side arm element S2of the third power conversion circuit section33to turn ON (conduction)/OFF (cutoff). For example, the gate drive unit29generates a gate signal of a duty ratio according to a boosted voltage command during boosting of the third power conversion circuit section33or a dropped voltage command during regeneration of the third power conversion circuit section33. The duty ratio is a ratio between the high side arm element S1and the low side arm element S2.

In the example shown inFIG. 10, while the power conversion device1of the first or second embodiment is applied to the vehicle10, in another example, the power conversion device1of the first or second embodiment may be applied between an alternating current motor and a direct current power source of, for example, an elevator, a pump, a fan, a railway vehicle, an air conditioner, a refrigerator, a washing machine, or the like, having an alternating current motor and a directing current power source in addition to the vehicle10.