Power semiconductor devices, power conversion devices and electric systems

Abstract

The power semiconductor device of the present invention includes: a circuit board having a positive electrode wiring connected to a first conductor on a high potential side and a negative electrode wiring connected to a fourth conductor on a low potential side on one side, and an output wiring connected to a second conductor and a third conductor opposite to the positive electrode wiring and the negative electrode wiring on another side; and a first capacitor for smoothing the DC power supplied to a first upper arm circuit and a first lower arm circuit, wherein the circuit board is disposed between the first upper arm circuit and the first lower arm circuit, the first capacitor is disposed between the first upper arm circuit and the first lower arm circuit, and is connected to the positive electrode wiring and the negative electrode wiring on the circuit board.

Description

Technical Field

[0001] This invention relates to power semiconductor devices, power conversion devices, and electric systems. Background Technology

[0002] The power conversion device includes a capacitor for smoothing DC power and a switching element for converting DC current to AC current. When the switching element operates, the rapid change in current generates a surge voltage proportional to the inductance of the wiring line, thus requiring a reduction in the wiring line inductance.

[0003] Patent document 1 discloses a semiconductor module that constitutes a three-phase inverter circuit with upper and lower arms of three phases. The semiconductor module has a multi-layer wiring busbar. In the multi-layer wiring busbar, the output wiring layer is composed of a U-phase wiring layer, a V-phase wiring layer and a W-phase wiring layer that are connected to the intermediate potential points of the upper and lower arms of the three phases.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2015-211524 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] The device in Patent Document 1 does not take into account the wiring, including the capacitor, and the wiring is too long, which does not reduce the inductance of the wiring.

[0009] Technical means to solve the problem

[0010] The power semiconductor device of the present invention includes a first upper arm circuit and a first lower arm circuit. The first upper arm circuit is formed by a first switching element sandwiched between a first conductor and a second conductor to form the upper arm circuit. The first lower arm circuit is formed by a second switching element sandwiched between a third conductor and a fourth conductor to form the lower arm circuit. The power semiconductor device includes: a circuit board having a positive terminal wiring connected to the first conductor on a high potential side and a negative terminal wiring connected to the fourth conductor on a low potential side on one side, and an output terminal wiring connected to the second conductor and the third conductor opposite to the positive terminal wiring and the negative terminal wiring on the other side; and a first capacitor for smoothing the DC power supplied to the first upper arm circuit and the first lower arm circuit. The circuit board is disposed between the first upper arm circuit and the first lower arm circuit, and the first capacitor is disposed between the first upper arm circuit and the first lower arm circuit and connected to the positive terminal wiring and the negative terminal wiring on the circuit board.

[0011] Invention Effects

[0012] The inductance of wiring circuits can be reduced by using this invention. Attached Figure Description

[0013] Figure 1 This is a cross-sectional view of a power semiconductor device.

[0014] Figure 2 This is an exploded perspective view of the main parts of the first upper arm circuit body of a power semiconductor device.

[0015] Figure 3 This is a circuit diagram of a power semiconductor device.

[0016] Figure 4 This is a three-dimensional view of the front of the circuit board of a power semiconductor device.

[0017] Figure 5 This is a three-dimensional view of the back of the circuit board of a power semiconductor device.

[0018] Figure 6 This is a wiring diagram of the front side of a power semiconductor device's circuit board.

[0019] Figure 7 This is the wiring diagram on the back of the circuit board of a power semiconductor device.

[0020] Figure 8 This is a three-dimensional diagram of a power conversion device.

[0021] Figure 9 This is a circuit diagram of a power conversion device.

[0022] Figure 10 It is an exploded 3D diagram of the electric system. Detailed Implementation

[0023] Embodiments of the present invention will now be described with reference to the accompanying drawings. The following description and drawings are examples for illustrating the present invention; appropriate omissions and simplifications have been made to make the description clearer. The present invention can also be implemented in various other ways. Unless otherwise specified, each constituent element can be single or multiple.

[0024] To facilitate understanding of the invention, the positions, sizes, shapes, and extents of the constituent elements shown in the accompanying drawings do not always represent their actual positions, sizes, shapes, and extents. Therefore, the invention is not necessarily limited to the positions, sizes, shapes, and extents disclosed in the accompanying drawings.

[0025] When multiple constituent elements have the same or equivalent functions, different suffixes are sometimes used to describe the same reference numeral. However, when it is not necessary to distinguish between these multiple constituent elements, the suffixes are sometimes omitted in the description.

[0026] [First Implementation Method]

[0027] Figure 1 This is a cross-sectional view of the power semiconductor device 100. This cross-sectional view will be described later. Figure 4 A cross-sectional view of line XX in the perspective view of the power semiconductor device 100 shown.

[0028] The power semiconductor device 100 includes a first upper arm circuit body 110U and a first lower arm circuit body 110L. The first upper arm circuit body 110U is constructed by sandwiching a first switching element 101 constituting the upper arm circuit with a first conductor 111 and a second conductor 112. The first lower arm circuit body 110L is constructed by sandwiching a second switching element 102 constituting the lower arm circuit with a third conductor 113 and a fourth conductor 114.

[0029] The positive terminal of the first switching element 101 is joined to the first conductor 111 by solder or the like, and the negative terminal is joined to the second conductor 112 by solder or the like. The first conductor 111 and the second conductor 112 are made of conductors such as copper or aluminum.

[0030] The positive terminal of the second switching element 102 is connected to the third conductor 113 via solder or the like, and the negative terminal is connected to the fourth conductor 114 via solder or the like. The third conductor 113 and the fourth conductor 114 are made of conductors such as copper or aluminum.

[0031] A circuit board 120 is disposed between the first upper arm circuit body 110U and the first lower arm circuit body 110L. The circuit board 120 is insulating and is made of resin or ceramic.

[0032] On one side of the circuit board 120 (the upper surface in the figure, hereinafter referred to as the front side), a positive terminal wiring 121 connected to the first conductor 111 on the high-potential side and a negative terminal wiring 122 connected to the fourth conductor 114 on the low-potential side are provided. On the other side of the circuit board 120 (the lower surface in the figure, hereinafter referred to as the back side), an output wiring 123 connected to the second conductor 112 and the third conductor 113 is provided opposite to the positive terminal wiring 121 and the negative terminal wiring 122. That is, the positive terminal wiring 121, the negative terminal wiring 122, and the output wiring 123 are stacked on the front and back sides of the circuit board 120. The positive terminal wiring 121, the negative terminal wiring 122, and the output wiring 123 are bonded to the circuit board 120 and formed into a pattern on the circuit board 120 by etching or the like. The output wiring 123 is connected to the output terminal conductor 125.

[0033] The first conductor 111 is connected to the positive terminal wiring 121 by solder or the like, the second conductor 112 is connected to the output wiring 123 by solder or the like, the third conductor 113 is connected to the output wiring 123 by solder or the like, and the fourth conductor 114 is connected to the negative terminal wiring 122 by solder or the like.

[0034] A first capacitor 130 is disposed between the first upper arm circuit body 110U and the first lower arm circuit body 110L. The positive terminal of the first capacitor 130 is connected to the positive wiring 121 on the circuit board 120 via solder or the like, and the negative terminal of the first capacitor 130 is connected to the negative wiring 122 on the circuit board 120 via solder or the like. The first capacitor 130 is used to smooth the DC power supplied to the first upper arm circuit body 110U and the first lower arm circuit body 110L. The first capacitor 130 is a small capacitor with high heat resistance, such as a ceramic capacitor or a film capacitor.

[0035] The gaps between the first upper arm circuit 110U, the first lower arm circuit 110L, the circuit board 120, and the first capacitor 130 are filled with molding resin. That is, the first upper arm circuit 110U, the first lower arm circuit 110L, the circuit board 120, and the first capacitor 130 are sealed with molding resin.

[0036] On the opposite surfaces of the first conductor 111 and the fourth conductor 114 to the surfaces of the first switching element 101 and the second switching element 102, a first cooler 151 is disposed with an insulator 141 in between. Only the cooling fins are shown in the first cooler 151, but the cooling fins are also omitted from the illustration as they are covered by a housing, and a cooling medium such as air or cooling water circulates inside.

[0037] On the opposite surfaces of the second conductor 112 and the third conductor 113 to the surfaces of the first switching element 101 and the second switching element 102, a second cooler 152 is disposed with an insulator 142 in between. Only the cooling fins are shown in the second cooler 152, but the cooling fins are also omitted from the diagram as they are covered by a housing, and a cooling medium such as air or cooling water circulates inside.

[0038] Insulators 141 and 142 are made of ceramic or resin sheets. Thermal grease or other heat-dissipating grease layers may also be applied to one or both sides of insulators 141 and 142.

[0039] The cooling fins of the first cooler 151 and the second cooler 152 are made of materials with high thermal conductivity, such as copper or aluminum. For the first cooler 151 and the second cooler 152, the surface area can be increased and the cooling performance improved by forming cooling fins or irregularities.

[0040] The upper surface of the first capacitor 130 is set lower than the upper surfaces of the first conductor 111 and the fourth conductor 114. In other words, an insulator 141 is disposed in close contact with the upper surfaces of the first conductor 111 and the fourth conductor 114, and a first cooler 151 is disposed with respect to the insulator 141, but a gap is provided between the upper surface of the first capacitor 130 and the insulator 141. Therefore, even if there are slight irregularities on the lower surface of the first cooler 151, the first cooler 151 can be made to fit tightly against the upper surfaces of the first conductor 111 and the fourth conductor 114 without interference from the first capacitor 130. As a result, the first cooler 151 is easy to form, and the cooling performance is improved. In addition, the gap between the upper surface of the first capacitor 130 and the insulator 141 is filled with molding resin.

[0041] In this embodiment, the first upper arm circuit 110U, the first capacitor 130 on the circuit board 120, and the first lower arm circuit 110L are arranged in a straight line. Furthermore, the positive terminal wiring 121 and the negative terminal wiring 122 are disposed on the front side of the circuit board 120, and the output wiring 123 is disposed on the back side of the circuit board 120; that is, the positive terminal wiring 121 and the negative terminal wiring 122 are positioned opposite to the output wiring 123, or in other words, they are stacked.

[0042] Figure 2 This is an exploded perspective view of the main parts of the first upper arm circuit body 110U of the power semiconductor device 100.

[0043] A control signal wiring 124 is derived from the gate electrode of the first switching element 101. The upper surface of the first switching element 101 is the emitter electrode, and the lower surface is the collector electrode. The emitter electrode of the first switching element 101 is... Figure 1 The diagram is omitted. It is bonded to the first conductor 111 via a bonding material 101D such as solder. The collector electrode of the first switching element 101 is bonded to the second conductor 112 via the bonding material 101D.

[0044] The first conductor 111 has a connection terminal 111E that connects to the positive wiring 121 on the circuit board 120. The second conductor 112 has a connection terminal 112C that connects to the output wiring 123 on the circuit board 120. Here, the connection terminals 111E and 112C are joined to the positive wiring 121 and the output wiring 123 on the circuit board 120 with a large area.

[0045] Figure 3 This is a circuit diagram of the power semiconductor device 100.

[0046] The power semiconductor device 100 includes a first switching element 101 constituting an upper arm circuit, a second switching element 102 constituting a lower arm circuit, and a first capacitor 130 arranged in parallel between the upper arm circuit and the lower arm circuit. A positive terminal wiring 121 is connected to the upper arm circuit, a negative terminal wiring 122 is connected to the lower arm circuit, and the connection point of the first switching element 101 and the second switching element 102 is connected to the output wiring 123.

[0047] The power semiconductor device 100 also includes a third switching element 103 forming an upper arm circuit and connected in parallel with the first switching element 101, a fourth switching element 104 forming a lower arm circuit and connected in parallel with the second switching element 102, and a second capacitor 131 arranged in parallel between the upper arm circuit and the lower arm circuit. The positive terminal wiring 121 is connected to the upper arm circuit, the negative terminal wiring 122 is connected to the lower arm circuit, and the connection point between the third switching element 103 and the fourth switching element 104 is connected to the output wiring 123.

[0048] Control signal wiring 124 (omitted from the diagram) is derived from the gate electrodes of the first switching element 101 and the fourth switching element 104, respectively. Figure 2 ).

[0049] The first switching element 101 and the fourth switching element 104 are power semiconductor devices composed of IGBTs or MOSFETs. The second switching element 102 and the third switching element 103 are diodes.

[0050] Figure 3 The circuit structure shown represents a portion of one phase of a power semiconductor device 100 used as an inverter to drive a motor. In this case, the power semiconductor device 100 can be configured as a phase using at least a first switching element 101, a second switching element 102, and a first capacitor 130.

[0051] Figure 4 This is a perspective view of the front of the circuit board 120 of the power semiconductor device 100. Figure 5 These are perspective views of the back of the circuit board 120 of the power semiconductor device 100. These views show the state after the first cooler 151 and the second cooler 152 have been removed.

[0052] The first upper arm circuit 110U, which is equipped with the first switching element 101, is connected in series with the first lower arm circuit 110L, which is equipped with the second switching element 102, via the output wiring 123 provided on the circuit board 120.

[0053] The second upper arm circuit 210U, which is equipped with the third switching element 103, is connected in series with the second lower arm circuit 210L, which is equipped with the fourth switching element 104, via the output wiring 123 provided on the circuit board 120.

[0054] The first upper arm circuit 110U, equipped with the first switching element 101, is connected in parallel with the second upper arm circuit 210U, equipped with the third switching element 103, via wiring provided on the circuit board 120. The first lower arm circuit 110L, equipped with the second switching element 102, is connected in parallel with the second lower arm circuit 210L, equipped with the fourth switching element 104, via wiring provided on the circuit board 120.

[0055] like Figure 4 As shown, the first capacitor 130 is disposed between the first upper arm circuit body 110U and the first lower arm circuit body 110L. Additionally, as... Figure 5 As shown, the second capacitor 131 is disposed between the second upper arm circuit body 210U and the second lower arm circuit body 210L.

[0056] Additionally, negative terminal wiring 122, as Figure 4 As shown, the positive terminal wire 121 is led out to the front side of the circuit board 120. Figure 5 As shown, it is exported to the back side of circuit board 120.

[0057] like Figure 5 As shown, the control signal wiring 124 of the first switching element 101 constituting the first upper arm circuit 101U and the control signal wiring 124 of the fourth switching element 104 constituting the second lower arm circuit 210L are arranged on the same surface of the circuit board 120 in the same direction. This allows for easy wire bonding of the control signal wiring 124.

[0058] Figure 6 This is a wiring diagram of the front side of the circuit board 120 of the power semiconductor device 100. Figure 7 This is a wiring diagram of the back side of the circuit board 120 of the power semiconductor device 100.

[0059] On the circuit board 120, through holes 110UH and 110LH are provided for configuring the first upper arm circuit body 110U and the first lower arm circuit body 110L, respectively, and through holes 210UH and 210LH are also provided for configuring the second upper arm circuit body 210U and the second lower arm circuit body 210L.

[0060] On the insulating layer of the circuit board 120, the positive terminal wiring 121, negative terminal wiring 122, output wiring 123, and control signal wiring 124 are patterned by etching or the like. The circuit board 120 is provided with through-holes 126, allowing the positive terminal wiring 121, negative terminal wiring 122, output wiring 123, and control signal wiring 124 to connect to each other between the front and back sides of the circuit board 120.

[0061] exist Figure 6Between the through holes 110UH and 110LH on the front side of the circuit board 120 shown, the positive and negative terminals of the first capacitor 130 are connected to the positive wiring 121 and the negative wiring 122. Here, the positive wiring 121 and the negative wiring 122 are formed with a large area so that they can be joined with a large area when connected to the first capacitor 130, the first conductor 111, and the fourth conductor 114.

[0062] exist Figure 7 Between the through holes 210UH and 210LH on the back side of the circuit board 120 shown, the positive and negative terminals of the second capacitor 131 are connected to the positive wiring 121 and the negative wiring 122. Here, the positive wiring 121 and the negative wiring 122 are formed with a large area, so that they can be joined with a large area when connected to the second capacitor 131, etc.

[0063] In addition, such as Figure 7 As shown, the control signal wiring 124 is arranged on the same side of the circuit board 120 with the same orientation. In addition, wiring terminals 127 connected to the third capacitor 310 described later are arranged on the circuit board 120.

[0064] For power semiconductor devices that do not utilize this embodiment, the power semiconductor device does not contain a capacitor. Therefore, the wiring from the switching element inside the power semiconductor device to the capacitor outside the power semiconductor device becomes longer, and the inductance of the wiring cannot be reduced.

[0065] In contrast, in this embodiment, the capacitor is also included inside the power semiconductor device 100, thus shortening the wiring from the switching element to the capacitor and reducing the inductance of the wiring.

[0066] Furthermore, in this embodiment, the positive terminal wiring 121 and negative terminal wiring 122 on the front side of the circuit board 120 are stacked with, or in other words, opposite to, the output wiring 123 on the back side of the circuit board 120. Here, refer to... Figure 1 The focus is on the current flowing from the positive terminal of the first capacitor 130 through the positive wiring 121, the first upper arm circuit 110U, the output wiring 123, the first lower arm circuit 110L, and the negative wiring 122 to the negative terminal of the first capacitor 130. The direction of this current flow in the positive wiring 121 on the front side of the circuit board 120 is opposite to the direction of flow in the output wiring 123 on the back side of the circuit board 120. Similarly, the direction of current flow in the output wiring 123 on the back side of the circuit board 120 is opposite to the direction of flow in the negative wiring 122 on the front side of the circuit board 120. Therefore, the magnetic flux generated by the flowing current is canceled out, the magnetic flux is reduced, and the inductance is reduced.

[0067] Furthermore, the positive terminal wiring 121, the negative terminal wiring 122, the output wiring 123, the first capacitor 130, and the first conductors 111 to 114 are joined together with a large area. As a result, the currents flowing in opposite directions flow in a larger area, which increases the canceling magnetic flux and more effectively reduces the inductance.

[0068] [Second Implementation]

[0069] Figure 8 This is a 3D view of the power conversion device 300.

[0070] The power conversion device 300 uses the power semiconductor device 100 described in the first embodiment and is configured as an inverter for driving an electric motor.

[0071] like Figure 8 As shown, power semiconductor devices 100U, 100V, and 100W are used as the U-phase, V-phase, and W-phase of the inverter, corresponding to a three-phase motor. The power semiconductor devices 100U, 100V, and 100W have the same structure as the power semiconductor device 100 described in the first embodiment. However, in this embodiment, the power semiconductor devices 100U, 100V, and 100W are configured on a single circuit board 120. Furthermore, a third capacitor 310 is connected to the wiring terminal 127 of the circuit board 120. The third capacitor 310 is a large-capacitance smooth capacitor, composed of a film capacitor or the like, and is connected in parallel with the first capacitor 130 and the second capacitor 131.

[0072] An inverter composed of power semiconductor devices 100U, 100V, and 100W converts DC power supplied by batteries into AC power to drive a motor.

[0073] The third capacitor 310 has a lower heat resistance temperature but a larger capacitance compared to the first capacitor 130 and the second capacitor 131. By arranging the first capacitor 130 and the second capacitor 131 close to the upper and lower arm circuit bodies to shorten their wiring length, it is possible to reduce the inductance of the wiring lines and suppress DC voltage fluctuations caused by increasing the capacitance by connecting the third capacitor 310 in parallel.

[0074] Figure 9 This is the circuit diagram of the power conversion device 300.

[0075] The power semiconductor device 100U, 100V, 100W is related to the reference. Figure 3 The power semiconductor device 100 described herein has the same structure. In this embodiment, the third capacitor 310 is connected between the DC wiring, namely the positive wiring 121 and the negative wiring 122. Furthermore, the power semiconductor devices 100U, 100V, and 100W are connected in parallel between the positive wiring 121 and the negative wiring 122.

[0076] Figure 10 This is an exploded 3D view of the electric system 600.

[0077] The electric system 600 consists of a power conversion device 300, an electric motor 400, and a transmission device 500.

[0078] The power conversion device 300 has a reference Figure 8 , Figure 9 The structure is described. Alternatively, the third capacitor 310 may be omitted. The power conversion device 300 converts DC power supplied from a battery or the like into AC power, and its output wiring 123 is connected to the windings of the motor 400 to drive the motor 400.

[0079] The electric motor 400 is driven by AC power output from the power conversion device 300, which generates torque on the output shaft 401.

[0080] The transmission device 500 is connected to the output shaft 401 of the motor 400 to change the speed of the output shaft 401. The power conversion device 300, the motor 400, and the transmission device 500 are fastened together as a single unit by small screws or the like.

[0081] The following effects can be achieved by implementing the methods described above.

[0082] (1) A power semiconductor device 100 includes a first upper arm circuit body 110U and a first lower arm circuit body 110L, wherein the first upper arm circuit body 110U is formed by a first switch element 101 constituting an upper arm circuit sandwiched between a first conductor 111 and a second conductor 112, and the first lower arm circuit body 110L is formed by a second switch element 102 constituting a lower arm circuit sandwiched between a third conductor 113 and a fourth conductor 114. The power semiconductor device 100 includes: a circuit board 120, on which a positive terminal wiring 121 connected to the first conductor 111 on the high potential side and a negative terminal wiring 121 connected to the fourth conductor 114 on the low potential side are disposed on one side. On the other side, opposite to the positive and negative wiring 121, there is an output wiring 123 connected to the second conductor 112 and the third conductor 113; and a first capacitor 130, which is used to smooth the DC power supplied to the first upper arm circuit 110U and the first lower arm circuit 110L. The circuit board 120 is disposed between the first upper arm circuit 110U and the first lower arm circuit 110L, and the first capacitor 130 is disposed between the first upper arm circuit 110U and the first lower arm circuit 110L and connected to the positive wiring 121 and the negative wiring 122 on the circuit board 120. This reduces the inductance of the wiring lines.

[0083] This invention is not limited to the embodiments described above. Other embodiments conceivable within the scope of the technical concept of this invention are also included within the scope of this invention, provided they do not impair the characteristics of the invention. Additionally, structures obtained by combining the above embodiments may also be employed.

[0084] Explanation of reference numerals in the attached figures

[0085] 100, 100U, 100V, 100W… Power semiconductor device, 101… First switching element, 101D… Bonding material, 102… Second switching element, 103… Third switching element, 104… Fourth switching element, 110U… First upper arm circuit body, 110L… First lower arm circuit body, 110UH, 110LH, 210UH, 210LH… Through hole, 111… First conductor, 111E, 112C… Connecting terminal, 112… Second conductor, 113… Third conductor, 114… …Fourth conductor, 120…Circuit board, 121…Positive wiring, 122…Negative wiring, 123…Output wiring, 124…Control signal wiring, 126…Through-through via, 127…Wiring terminal, 130…First capacitor, 131…Second capacitor, 141, 142…Insulator, 151…First cooler, 152…Second cooler, 300…Power conversion device, 310…Third capacitor, 400…Motor, 401…Output shaft, 500…Transmission device, 600…Electric system.

Claims

1. A power semiconductor device comprising a first upper arm circuit and a first lower arm circuit, wherein the first upper arm circuit is formed by a first switching element sandwiched between a first conductor and a second conductor to form the upper arm circuit, and the first lower arm circuit is formed by a second switching element sandwiched between a third conductor and a fourth conductor to form the lower arm circuit, characterized in that, include: A circuit board, having a positive terminal wiring connected to a first conductor on a high-potential side and a negative terminal wiring connected to a fourth conductor on a low-potential side on one side, and an output terminal wiring connected to a second conductor and a third conductor opposite to the positive and negative terminal wiring on another side; and A first capacitor is used to smooth the DC power supplied to the first upper arm circuit body and the first lower arm circuit body, wherein... The circuit board is positioned between the first upper arm circuit body and the first lower arm circuit body. The first capacitor is disposed between the first upper arm circuit body and the first lower arm circuit body, and is connected to the positive terminal wiring and the negative terminal wiring on the circuit board.

2. The power semiconductor device as claimed in claim 1, characterized in that: On the opposite surfaces of the first conductor and the fourth conductor to the surfaces opposite the first and second switching elements, a first cooler is disposed, separated by an insulator. A second cooler is provided on the opposite side of the second conductor and the third conductor to the surfaces opposite to the first and second switching elements, separated by an insulator.

3. The power semiconductor device as described in claim 1 or 2, characterized in that: The upper surface of the first capacitor is set lower than the upper surfaces of the first conductor and the fourth conductor.

4. The power semiconductor device as claimed in claim 1, characterized in that: The system includes a second upper arm circuit, a second lower arm circuit, and a second capacitor. The second upper arm circuit includes a third switching element connected in parallel with the first switching element, and the second lower arm circuit includes a fourth switching element connected in parallel with the second switching element. The second capacitor is used to smooth the DC power supplied to the second upper arm circuit and the second lower arm circuit. The second capacitor is disposed between the second upper arm circuit body and the second lower arm circuit body, and is connected to the positive terminal wiring and the negative terminal wiring on the circuit board.

5. The power semiconductor device as claimed in claim 4, characterized in that: The first upper arm circuit body and the first lower arm circuit body are arranged side by side, as are the second upper arm circuit body and the second lower arm circuit body. The control signal wiring of the first switching element constituting the first upper arm circuit body and the control signal wiring of the fourth switching element constituting the second lower arm circuit body are oriented in the same direction.

6. A power conversion device, characterized in that: Multiple power semiconductor devices as described in claim 4 are connected in parallel using DC wiring.

7. The power conversion device as described in claim 6, characterized in that: A third capacitor is provided on the DC wiring line corresponding to the power semiconductor device.

8. An electric system, characterized in that, Integrated with: The power conversion device as described in claim 6 or 7; An electric motor, which is driven by alternating current output from the power conversion device; and A transmission device, which is connected to the output shaft of the motor, is capable of changing the rotational speed of the output shaft.

Images