Power conversion device

Abstract

To provide a power conversion device capable of cooling a plurality of switching elements.SOLUTION: A power conversion device comprises: a substrate in which a conductive pattern is formed and on which a plurality of switching elements for power conversion is mounted; and a cooler which cools the plurality of switching elements. The substrate includes a first surface on which the plurality of switching elements is mounted, the cooler is opposed to the first surface, and the switching element is a chip type surface mounted component.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a power conversion device.

Background Art

[0002] There is known a power conversion device including an electrical component mounted on a circuit board, a heat sink that dissipates heat generated by the electrical component, and a box-shaped housing that houses the electrical component and the heat sink (see, for example, Patent Document 1). Further, there is known a power conversion device including a cooler that cools a plurality of semiconductor modules and a support frame provided on the cooler, and the plurality of semiconductor modules are supported by the support frame (see, for example, Patent Document 2). Furthermore, there is known a power conversion device including a plurality of semiconductor modules, a cooler that cools the plurality of semiconductor modules, and a case that houses the plurality of semiconductor modules and the cooler (see, for example, Patent Document 3).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] The power conversion device includes a substrate on which a plurality of switching elements for power conversion are mounted.

[0005] The present disclosure provides a power conversion device capable of cooling a plurality of switching elements.

Means for Solving the Problems

[0006] The present disclosure A substrate on which a conductive pattern is formed and a plurality of switching elements for power conversion are mounted, and a cooler for cooling the plurality of switching elements. The substrate has a first surface on which the plurality of switching elements are mounted, The cooler faces the first surface, The switching element is a chip-type surface mount component. A power conversion device is provided.

Advantages of the Invention

[0007] According to the present disclosure, a power conversion device capable of cooling a plurality of switching elements can be provided.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings. Note that, in directions such as parallel, perpendicular, orthogonal, horizontal, vertical, up and down, left and right, a deviation that does not impair the effects of the present invention may be allowed. Also, the X-axis direction, Y-axis direction, and Z-axis direction respectively represent a direction parallel to the X-axis, a direction parallel to the Y-axis, and a direction parallel to the Z-axis. The X-axis direction, Y-axis direction, and Z-axis direction are orthogonal to each other. The XY plane, YZ plane, and ZX plane respectively represent a virtual plane parallel to the X-axis direction and the Y-axis direction, a virtual plane parallel to the Y-axis direction and the Z-axis direction, and a virtual plane parallel to the Z-axis direction and the X-axis direction. Also, the shape of each part shown in each figure is an example, and the present invention is not limited to this example.

[0010] FIG. 1 is a circuit diagram showing a configuration example of a power conversion device in an embodiment. The power conversion device 101 shown in FIG. 1 is an inverter that converts DC input power supplied from a pair of power supply terminals, a positive terminal 8p and a negative terminal 9n, into desired AC output power. The power conversion device 101 is used, for example, as an inverter that drives a motor M2 that rotates the wheels of a vehicle. The use of the power conversion device according to the present disclosure is not limited to this.

[0011] The power conversion device 101 includes a positive terminal 8p, a negative terminal 9n, a plurality of output terminals 2u, 2v, 2w, a capacitor 56, a power conversion circuit 20, a positive wiring 83, a negative wiring 93, a plurality of current sensors 28u, 28v, 28w, a control circuit 17, and a drive circuit 18. The positive wiring 83 has a first positive wiring 80 and a second positive wiring 57. The negative wiring 93 has a first negative wiring 90 and a second negative wiring 58. Either the control circuit 17 or both the control circuit 17 and the drive circuit 18 may be provided in an external device separate from the power conversion device 101.

[0012] The positive terminal 8p and the negative terminal 9n are external terminals to which a DC power supply voltage is applied by a DC power supply (not shown). The potential of the positive terminal 8p is higher than the potential of the negative terminal 9n. Specific examples of the DC power supply include a battery, a converter, and a regulator.

[0013] The plurality of output terminals 2u, 2v, 2w are external terminals for inputting and outputting three-phase AC power, to which a motor M2 is connected.

[0014] The capacitor 56 is a capacitive element that smoothes the DC power supply voltage applied between the positive terminal 8p and the negative terminal 9n. Specific examples thereof include an electrolytic capacitor. The capacitor 56 has a first capacitor electrode 51 and a second capacitor electrode 52. The first capacitor electrode 51 is a terminal electrically connected to the positive wiring 83 (the first positive wiring 80 and the second positive wiring 57), and the second capacitor electrode 52 is a terminal electrically connected to the negative wiring 93 (the first negative wiring 90 and the second negative wiring 58).

[0015] The power conversion circuit 20 is an inverter circuit that converts the DC power input from the positive terminal 8p and the negative terminal 9n to the positive wiring 83 and the negative wiring 93 into three-phase AC power supplied to the motor M2.

[0016] The power conversion circuit 20 is a three-phase bridge circuit having a plurality of switching elements 21u, 21v, 21w, 22u, 22v, 22w, and generates three-phase AC power by switching the plurality of switching elements 21u, 21v, 21w, 22u, 22v, 22w. The power conversion circuit 20 has a plurality of switching elements 21u, 21v, 21w, 22u, 22v, 22w and a plurality of output wirings 1u, 1v, 1w.

[0017] The U-phase switching elements 21u, 22u are connected in series with each other, and the connection node therebetween is connected to the U-phase output terminal 2u connected to the U-phase coil of the motor M2. The V-phase switching elements 21v, 22v are connected in series with each other, and the connection node therebetween is connected to the V-phase output terminal 2v connected to the V-phase coil of the motor M2. The W-phase switching elements 21w, 22w are connected in series with each other, and the connection node therebetween is connected to the W-phase output terminal 2w connected to the W-phase coil of the motor M2.

[0018] The switching elements 21u, 21v, 21w are semiconductor elements each having a first main electrode 23u, 23v, 23w, a second main electrode 25u, 25v, 25w, and a first control electrode 14u, 14v, 14w. The first main electrodes 23u, 23v, 23w are all electrically connected to the second positive electrode wiring 57. The second main electrodes 25u, 25v, 25w are each electrically connected to the corresponding output wiring 1u, 1v, 1w and are electrically connected to the corresponding output terminals 2u, 2v, 2w via the corresponding output wirings 1u, 1v, 1w. The first control electrodes 14u, 14v, 14w are all electrically connected to the drive circuit 18.

[0019] The switching elements 22u, 22v, and 22w are semiconductor elements each having a third main electrode 29u, 29v, 29w, a fourth main electrode 24u, 24v, 24w, and a second control electrode 15u, 15v, 15w. The third main electrodes 29u, 29v, 29w are each electrically connected to the corresponding output wiring 1u, 1v, 1w and are electrically connected to the corresponding output terminals 2u, 2v, 2w via the corresponding output wiring 1u, 1v, 1w. The fourth main electrodes 24u, 24v, 24w are all electrically connected to the second negative electrode wiring 58. The second control electrodes 15u, 15v, 15w are all electrically connected to the drive circuit 18.

[0020] In the switching elements 21u, 21v, 21w, a diode is connected in anti-parallel between the first main electrode and the second main electrode. In the switching elements 22u, 22v, 22w, a diode is connected in anti-parallel between the third main electrode and the fourth main electrode.

[0021] The switching elements 21u, 21v, 21w are voltage-driven semiconductor elements each having a control electrode (gate), a first main electrode (collector or drain), and a second main electrode (emitter or source). The switching elements 22u, 22v, 22w are voltage-driven semiconductor elements each having a control electrode (gate), a third main electrode (collector or drain), and a fourth main electrode (emitter or source). Specific examples of the switching element include a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), an IGBT (Insulated Gate Bipolar Transistor), and the like. FIG. 1 illustrates the case where the switching elements 21u, 21v, 21w, 22u, 22v, 22w are IGBTs each having a gate, a collector, and an emitter.

[0022] The switching elements 21u, 21v, 21w, 22u, 22v, 22w may be switching elements including a semiconductor such as Si (silicon), or may be switching elements including a wide bandgap semiconductor such as SiC (silicon carbide), GaN (gallium nitride), Ga2O3 (gallium oxide), or diamond. By applying a wide bandgap semiconductor to the switching element, the effect of reducing the loss of the switching element is enhanced.

[0023] The positive electrode wiring 83 and the negative electrode wiring 93 are conductive wiring members to which a DC power supply voltage is applied via the positive electrode terminal 8p and the negative electrode terminal 9n, and DC power from a DC power supply (not shown) connected via the positive electrode terminal 8p and the negative electrode terminal 9n is supplied.

[0024] The positive electrode wiring 83 is a conductive member electrically connected to the positive electrode terminal 8p, the first capacitor electrode 51, and the first main electrodes 23u, 23v, 23w. The positive electrode wiring 83 is formed of one or a plurality of members, and in this example, includes a first positive electrode wiring 80 and a second positive electrode wiring 57. The first positive electrode wiring 80 is a wiring member electrically connected between the positive electrode terminal 8p and the first capacitor electrode 51. The second positive electrode wiring 57 is a wiring member electrically connected between the first capacitor electrode 51 and the first main electrodes 23u, 23v, 23w.

[0025] The negative electrode wiring 93 is a conductive member electrically connected to the negative electrode terminal 9n, the second capacitor electrode 52, and the fourth main electrodes 24u, 24v, 24w. The negative electrode wiring 93 is formed of one or a plurality of members, and in this example, includes a first negative electrode wiring 90 and a second negative electrode wiring 58. The first negative electrode wiring 90 is a wiring member electrically connected between the negative electrode terminal 9n and the second capacitor electrode 52. The second negative electrode wiring 58 is a wiring member electrically connected between the second capacitor electrode 52 and the fourth main electrodes 24u, 24v, 24w.

[0026] The output wiring 1u is a conductive wiring member electrically connected to the output terminal 2u, the second main electrode 25u, and the third main electrode 29u. The output wiring 1v is a conductive wiring member electrically connected to the output terminal 2v, the second main electrode 25v, and the third main electrode 29v. The output wiring 1w is a conductive wiring member electrically connected to the output terminal 2w, the second main electrode 25w, and the third main electrode 29w. The output wirings 1u, 1v, and 1w may each be formed from one or a plurality of members.

[0027] The current sensor 28u for the U phase detects the U-phase current flowing through the U-phase output wiring 1u and outputs a U-phase current detection signal representing the magnitude of the detected U-phase current to the control circuit 17. The current sensor 28v for the V phase detects the V-phase current flowing through the V-phase output wiring 1v and outputs a V-phase current detection signal representing the magnitude of the detected V-phase current to the control circuit 17. The current sensor 28w for the W phase detects the W-phase current flowing through the W-phase output wiring 1v and outputs a W-phase current detection signal representing the magnitude of the detected W-phase current to the control circuit 17.

[0028] The control circuit 17 generates a control signal (for example, a pulse width modulation signal) for generating three-phase AC power from DC power using at least two of the U-phase current detection signal, the V-phase current detection signal, and the W-phase current detection signal by a known method.

[0029] The drive circuit 18 generates a plurality of drive signals for driving the switching elements 21u, 21v, 21w, 22u, 22v, 22w so that three-phase AC power is generated according to the control signal supplied from the control circuit 17 by a known method. The drive circuit 18 supplies those plurality of drive signals to the corresponding control electrodes 14u, 14v, 14w, 15u, 15v, 15w. Thereby, a three-phase alternating current can be passed through the motor M2.

[0030] Next, before describing the power conversion device in one embodiment, a first structural example of the power conversion device in a comparative form will be described with reference to FIGS. 2 and 3. FIG. 2 is an exploded perspective view showing the first structural example of the power conversion device in a comparative form. FIG. 3 is a plan view showing the first structural example of the power conversion device in a comparative form. For the sake of clarity in showing the internal structure of the housing 6 that forms the outer shape of the power conversion device, for convenience, in FIG. 2, the illustration of the housing 6 is omitted, and in FIG. 3, the illustration of the control board 16 is omitted. The power conversion device 100 in the comparative form shown in FIGS. 2 and 3 has the circuit configuration shown in FIG. 1.

[0031] The power conversion device 100 includes a housing 6, a power connector 7, an output connector 2, a capacitor 56, a power conversion module 19, a control board 16, a plurality of bus bars such as a first positive bus bar 80b, a current sensor module 28, and a cooler 30.

[0032] The housing 6 houses various internal components of the power conversion device 100. The power connector 7 is connected to a power harness (not shown), and is connected to a DC power source (not shown) via the power harness. The output connector 2 is connected to an output harness (not shown), and is connected to a motor M2 (see FIG. 1) via the output harness. In this example, the power connector 7 and the output connector 2 are separate members, but they may also be integrated members.

[0033] The power connector 7 protrudes from the housing 6 and is fixed to the housing 6. The power connector 7 has a positive terminal 8p and a negative terminal 9n.

[0034] The output connector 2 protrudes from the housing 6 and is fixed to the housing 6. The output connector 2 has a plurality of output terminals 2u, 2v, 2w.

[0035] The capacitor 56 is housed in the housing 6. The capacitor 56 has a first capacitor electrode 51 and a second capacitor electrode 52 that are provided apart from each other in the Y-axis direction.

[0036] The power conversion module 19 is a package component incorporating switching elements 21u, 21v, 21w, 22u, 22v, and 22w.

[0037] The control board 16 has a drive circuit 18 and a control circuit 17 mounted thereon. The drive circuit 18 drives the switching elements 21u, 21v, 21w, 22u, 22v, and 22w within the power conversion module 19 so that three-phase AC power is generated according to the control signals supplied from the control circuit 17.

[0038] The first positive bus bar 80b is a member forming a first positive wiring 80 (FIG. 1) that is electrically connected between the positive terminal 8p and the first capacitor electrode 51. The first negative bus bar 90b is a member forming a first negative wiring 90 (FIG. 1) that is electrically connected between the negative terminal 9n and the second capacitor electrode 52.

[0039] The second positive bus bars 23ub, 23vb, and 23wb are members forming a second positive wiring 57 that is electrically connected between the first capacitor electrode 51 and the first main electrodes 23u, 23v, and 23w. At least a part of the bus bar forming the second positive wiring 57 is covered by the capacitor 56.

[0040] The second negative bus bars 24ub, 24vb, and 24wb are members forming a second negative wiring 58 that is electrically connected between the second capacitor electrode 52 and the fourth main electrodes 24u, 24v, and 24w. At least a part of the bus bar forming the second negative wiring 58 is covered by the capacitor 56.

[0041] The first U-phase bar 27ub and the second U-phase bar 26ub are members that form the output wiring 1u (Figure 1) electrically connected to the output terminal 2u, the second main electrode 25u, and the third main electrode 29u. The first V-phase bar 27vb and the second V-phase bar 26vb are members that form the output wiring 1v (Figure 1) electrically connected to the output terminal 2v, the second main electrode 25v, and the third main electrode 29v. The first W-phase bar 27wb and the second W-phase bar 26wb are members that form the output wiring 1w (Figure 1) electrically connected to the output terminal 2w, the second main electrode 25w, and the third main electrode 29w.

[0042] The current sensor module 28 is a package component incorporating the current sensors 28u, 28v, and 28w.

[0043] The cooler 30 cools the power conversion module 19. The cooler 30 has a cooling pipe 33, a supply pipe 34, and a discharge pipe 35. The cooling pipe 33 extends in the Y-axis direction and has one or a plurality of flow paths through which a refrigerant such as cooling water flows. The supply pipe 34 is a member that supplies the refrigerant flowing in from the inlet to the cooling pipe 33. The discharge pipe 35 is a member that discharges the refrigerant flowing out from the cooling pipe 33 from the outlet.

[0044] In the power conversion device 100, the capacitor 56 and the power conversion module 19 are connected in the shortest way, and the output side of the power conversion module 19 is connected to the output connector 2 via the current sensor module 28. Therefore, various internal components are arranged side by side as shown in Figures 2 and 3. However, there may be cases where the customer requests a change in the positions of the input / output connectors (the power connector 7 and the output connector 2). In this case, in order to cope with the change in the positions of the input / output connectors, it may be necessary to change the layout of components, bus bars, etc. and the terminal positions of the power conversion module 19.

[0045] For example, assume there is a customer requirement to change the position of the input / output connector from the side surface facing the positive X-axis direction of the housing 6 (FIG. 3) to the side surface facing the positive Y-axis direction of the housing 6 (FIG. 4). In this case, in addition to layout changes such as the cooler 30, the power conversion module 19, the current sensor module 28, and each bus bar, it may be necessary to customize the terminal positions of the power conversion module 19. Thus, in the power conversion device 100 in a comparative form, with the change in the position of the input / output connector, losses in time and cost due to new design changes will occur.

[0046] In contrast, in the power conversion device according to an embodiment of the present disclosure, at least a part of the plurality of wirings is formed not by bus bars but by conductive patterns formed on a substrate. Thereby, since the change in the position of the connector can be dealt with by changing the conductive patterns formed on the substrate, compared with the form dealt with by changing the bus bars, it is possible to flexibly respond to design changes accompanying the change in the position of the connector. Next, each structural example of the power conversion device in an embodiment will be described in detail.

[0047] FIG. 5 is an exploded perspective view showing a first structural example of a power conversion device in an embodiment. FIG. 6 is a plan view showing a first structural example of a power conversion device in an embodiment. For the sake of clarity in showing the internal structure of the housing 6 that forms the outer shape of the power conversion device, for convenience, FIG. 5 omits the illustration of the housing 6. The power conversion device 101 in the embodiment shown in FIGS. 5 and 6 has the circuit configuration shown in FIG. 1.

[0048] The power conversion device 101 includes a housing 6, a power connector 7, an output connector 2, a capacitor 56, switching elements 21u, 21v, 21w, 22u, 22v, 22w, a substrate 40, a plurality of patterns such as a first positive electrode pattern 80p, a current sensor circuit 28p, and a cooler 30.

[0049] The housing 6 houses various internal components of the power conversion device 101 (in this case, the capacitor 56, the cooler 30, and the substrate 40 on which the switching element 21u etc. are mounted). In this example, the housing 6 is a hexahedral box, but it may also be a polyhedral box of other shapes. The housing 6 has housing surfaces 6a, 6b facing each other in the X-axis direction, 6c, 6d facing each other in the Y-axis direction, and housing surfaces facing each other in the Z-axis direction. The housing 6 has a configuration including, for example, a case to which various internal components are directly or indirectly attached, and a cover that covers the various internal components on the case.

[0050] The power connector 7 is connected to a power harness (not shown), and is connected to a DC power source (not shown) via the power harness. The output connector 2 is connected to an output harness (not shown), and is connected to the motor M2 (see FIG. 1) via the output harness. In this example, the power connector 7 and the output connector 2 are separate members, but they may also be integrated members.

[0051] The power connector 7 is a component arranged on the side of the housing surface 6a so as to protrude from the housing surface 6a. The power connector 7 is exposed from the housing surface 6a of the housing 6 and is fixed to the housing surface 6a. The power connector 7 has a positive terminal 8p and a negative terminal 9n. The positive terminal 8p and the negative terminal 9n are exposed from the housing surface 6a of the housing 6.

[0052] The output connector 2 is a component arranged on the side of the housing surface 6a so as to protrude from the housing surface 6a. That is, the output connector 2 is arranged on the same side of the housing surface 6a as the power connector 7. The output connector 2 is exposed from the housing surface 6a of the housing 6 and is fixed to the housing surface 6a. The output connector 2 has a plurality of output terminals 2u, 2v, 2w. The plurality of output terminals 2u, 2v, 2w are exposed from the housing surface 6a of the housing 6.

[0053] The capacitor 56 is housed in the housing 6. The capacitor 56 has a first capacitor electrode 51 and a second capacitor electrode 52 that are provided apart from each other in the Y-axis direction. The first capacitor electrode 51 is a terminal provided on the negative Y-axis direction side of the capacitor 56, and protrudes from the capacitor surface 56a in the positive Z-axis direction of the capacitor 56. The second capacitor electrode 52 is a terminal provided on the positive Y-axis direction side of the capacitor 56, and protrudes from the capacitor surface 56a in the positive Z-axis direction of the capacitor 56.

[0054] The switching elements 21u, 21v, 21w are arranged side by side in the Y-axis direction. The switching elements 22u, 22v, 22w are arranged side by side in the Y-axis direction on the side in the X-axis direction (in this example, the positive X-axis direction) with respect to the switching elements 21u, 21v, 21w. The plurality of switching elements 21u, 21v, 21w, 22u, 22v, 22w for power conversion are chip-type surface mount components mounted on the lower surface 46 of the substrate 40.

[0055] The substrate 40 has a lower surface 46 facing the upper surface 33a of the cooler 30 and an upper surface 47 opposite to the lower surface 46. For example, the drive circuit 18 and the control circuit 17 are mounted on the substrate 40. The drive circuit 18 drives the switching elements 21u, 21v, 21w, 22u, 22v, 22w so that three-phase AC power is generated according to the control signal supplied from the control circuit 17.

[0056] The first positive electrode pattern 80p forms a first positive electrode wiring 80 (FIG. 1) that is electrically connected between the positive electrode terminal 8p and the first capacitor electrode 51. The first positive electrode pattern 80p is a conductive power supply wiring pattern formed on the substrate 40. The first negative electrode pattern 90p forms a first negative electrode wiring 90 (FIG. 1) that is electrically connected between the negative electrode terminal 9n and the second capacitor electrode 52. The first negative electrode pattern 90p is a conductive power supply wiring pattern formed on the substrate 40.

[0057] The second positive electrode pattern 23up, the third positive electrode pattern 23vp, and the fourth positive electrode pattern 23wp form a second positive electrode wiring 57 that is electrically connected between the first capacitor electrode 51 and the first main electrodes 23u, 23v, 23w. The second positive electrode pattern 23up, the third positive electrode pattern 23vp, and the fourth positive electrode pattern 23wp are conductive power supply wiring patterns formed on the substrate 40.

[0058] The second negative electrode pattern 24up, the third negative electrode pattern 24vp, and the fourth negative electrode pattern 24wp form a second negative electrode wiring 58 that is electrically connected between the second capacitor electrode 52 and the fourth main electrodes 24u, 24v, 24w. The second negative electrode pattern 24up, the third negative electrode pattern 24vp, and the fourth negative electrode pattern 24wp are conductive power supply wiring patterns formed on the substrate 40.

[0059] The U-phase pattern 27up forms an output wiring 1u (FIG. 1) that is electrically connected to the output terminal 2u, the second main electrode 25u, and the third main electrode 29u. The V-phase pattern 27vp forms an output wiring 1v (FIG. 1) that is electrically connected to the output terminal 2v, the second main electrode 25v, and the third main electrode 29v. The W-phase pattern 27wp forms an output wiring 1w (FIG. 1) that is electrically connected to the output terminal 2w, the second main electrode 25w, and the third main electrode 29w. The U-phase pattern 27up, the V-phase pattern 27vp, and the W-phase pattern 27wp are conductive power supply wiring patterns formed on the substrate 40.

[0060] The current sensor circuit 28p detects the U-phase current flowing through the U-phase pattern 27up, the V-phase current flowing through the V-phase pattern 27vp, and the W-phase current flowing through the W-phase pattern 27wp. The current sensor circuit 28p is electrically connected to the control circuit 17 and outputs a current detection signal for each phase to the control circuit 17.

[0061] The cooler 30 cools the switching elements 21u, 21v, 21w and the switching elements 22u, 22v, 22w. The cooler 30 extends in the Y-axis direction and is located between the capacitor 56 and the input / output connectors (the power connector 7 and the output connector 2). The cooler 30 has a cooling pipe 33, a supply pipe 34, and a discharge pipe 35.

[0062] The cooling pipe 33 extends in the Y-axis direction and has one or a plurality of flow paths through which a refrigerant such as cooling water flows. The supply pipe 34 is a member that supplies the refrigerant flowing in from the inlet to the cooling pipe 33. The discharge pipe 35 is a member that discharges the refrigerant flowing out from the cooling pipe 33 from the outlet.

[0063] The cooling pipe 33 has an upper surface 33a that faces the lower surface 46 of the substrate 40 in the Z-axis direction. The cooler 30 can be efficiently cooled by heat exchange with the plurality of switching elements 21u, 21v, 21w, 22u, 22v, 22w when the upper surface 33a contacts the plurality of switching elements 21u, 21v, 21w, 22u, 22v, 22w (specifically, the back surface opposite to the mounting surface).

[0064] Thus, the power conversion device 101 includes a plurality of wirings including a plurality of power supply wirings electrically connected to the capacitor 56, the plurality of switching elements, and the power connector 7, and a plurality of output wirings electrically connected to the plurality of switching elements and the output connector 2. And at least one of those plurality of wirings is a wiring including a conductive pattern formed on the substrate 40.

[0065] More specifically, in the power conversion device 101, the plurality of first power supply wirings electrically connected between the power supply connector 7 and the capacitor 56 are wirings including conductive power supply wiring patterns formed on the substrate 40. In this example, the plurality of first power supply wirings (the first positive electrode wiring 80 and the first negative electrode wiring 90) are wirings including conductive power supply wiring patterns (the first positive electrode pattern 80p and the first negative electrode pattern 90p) formed on the substrate 40. Thereby, since the change in the position of the power supply connector 7 can be accommodated by changing the first positive electrode pattern 80p and the first negative electrode pattern 90p, it is possible to flexibly respond to the design change accompanying the change in the position of the power supply connector 7. For example, when changing the position of the power supply connector 7 from the housing surface 6a (FIG. 6) on the positive X-axis direction side of the housing 6 to the housing surface 6c (FIG. 7) on the positive Y-axis direction side of the housing 6, it is possible to flexibly respond by changing the wiring layout of the first positive electrode pattern 80p and the first negative electrode pattern 90p. Note that at least one of the first positive electrode wiring 80 and the first negative electrode wiring 90 may be a wiring including a conductive power supply wiring pattern formed on the substrate 40. Alternatively, neither the first positive electrode wiring 80 nor the first negative electrode wiring 90 needs to be a wiring including a conductive power supply wiring pattern formed on the substrate 40.

[0066] In the power conversion device 101, the plurality of second power supply wirings electrically connected between the capacitor 56 and the plurality of switching elements are wirings including conductive power supply wiring patterns formed on the substrate 40. In this example, the plurality of second power supply wirings (second positive electrode wiring 57 and second negative electrode wiring 58) are wirings including conductive power supply wiring patterns (second positive electrode pattern 23up, third positive electrode pattern 23vp, fourth positive electrode pattern 23wp, second negative electrode pattern 24up, third negative electrode pattern 24vp, and fourth negative electrode pattern 24wp) formed on the substrate 40. Accordingly, since the change in the position of the power connector 7 can be dealt with by changing the second positive electrode pattern 23up or the like, the design change associated with the change in the position of the power connector 7 can be flexibly coped with. For example, with respect to the change in the position of the power connector 7 from the housing surface 6a (FIG. 6) on the positive X-axis direction side of the housing 6 to the housing surface 6c (FIG. 7) on the positive Y-axis direction side of the housing 6, it can be flexibly coped with by changing the wiring layout such as the second positive electrode pattern 23up. Note that at least one of the second positive electrode wiring 57 and the second negative electrode wiring 58 may be a wiring including a conductive power supply wiring pattern formed on the substrate 40. Alternatively, neither the second positive electrode wiring 57 nor the second negative electrode wiring 58 may be a wiring including a conductive power supply wiring pattern formed on the substrate 40.

[0067] In the power conversion device 101, the plurality of output wirings electrically connected between the output connector 2 and the plurality of switching elements are wirings including conductive output wiring patterns formed on the substrate 40. In this example, the plurality of output wirings (output wirings 1u, 1v, 1w) are wirings including conductive output wiring patterns (U-phase pattern 27up, V-phase pattern 27vp, and W-phase pattern 27wp) formed on the substrate 40. Thereby, since the change in the position of the output connector 2 can be accommodated by changing the U-phase pattern 27up, the V-phase pattern 27vp, and the W-phase pattern 27wp, it is possible to flexibly respond to the design changes accompanying the change in the position of the output connector 2. For example, when changing the position of the output connector 2 from the housing surface 6a (FIG. 6) on the positive X-axis direction side of the housing 6 to the housing surface 6c (FIG. 7) on the positive Y-axis direction side of the housing 6, it is possible to flexibly respond by changing the wiring layout such as the U-phase pattern 27up. Note that at least one of the output wirings 1u, 1v, 1w may be a wiring including a conductive power supply wiring pattern formed on the substrate 40. Alternatively, the output wirings 1u, 1v, 1w may not all be wirings including a conductive power supply wiring pattern formed on the substrate 40.

[0068] Also, the current sensor circuit 28p is a current sensor mounted on the substrate 40, and detects the current flowing through the U-phase pattern 27up, the V-phase pattern 27vp, and the W-phase pattern 27wp. By adopting such a current sensor circuit 28p, it is possible to flexibly respond to the design changes accompanying the change in the position of the output connector 2.

[0069] Further, the capacitor 56 has a plurality of capacitor electrodes (a first capacitor electrode 51 and a second capacitor electrode 52) provided on the upper surface (in this example, the capacitor surface 56a) facing the lower surface 46 of the substrate 40. The first capacitor electrode 51 is electrically connected to the power supply wiring patterns of the plurality of second power supply wirings (in this example, the second positive electrode pattern 23up, the third positive electrode pattern 23vp, and the fourth positive electrode pattern 23wp). The second capacitor electrode 52 is electrically connected to the power supply wiring patterns of the plurality of second power supply wirings (in this example, the second negative electrode pattern 24up, the third negative electrode pattern 24vp, and the fourth negative electrode pattern 24wp). Thus, since the plurality of capacitor electrodes are electrically connected to the power supply wiring patterns of the plurality of second power supply wirings, it is possible to flexibly respond to design changes accompanying the position change of the power connector 7.

[0070] Further, the substrate 40 has a lower surface 46 facing the upper surface 33a of the cooler 30, and the plurality of switching elements 21u etc. are mounted on the lower surface 46. Thereby, since it is easy to change the arrangement position of each of the plurality of switching elements 21u etc. on the lower surface 46, it is possible to flexibly respond to design changes accompanying the position change of the power connector 7 or the output connector 2.

[0071] Further, the drive circuit 18 that drives the plurality of switching elements 21u etc. may be mounted on the common substrate 40 on which the plurality of switching elements 21u etc. are mounted, or may be mounted on another substrate. By mounting the drive circuit 18 on the common substrate 40 with the plurality of switching elements 21u etc., the power conversion device 101 can be miniaturized compared to a form mounted on another substrate.

[0072] Further, the control circuit 17 that supplies a control signal to the drive circuit 18 may be mounted on the common substrate 40 on which the plurality of switching elements 21u etc. are mounted, or may be mounted on another substrate. By mounting the control circuit 17 on the common substrate 40 with the plurality of switching elements 21u etc., the power conversion device 101 can be miniaturized compared to a form mounted on another substrate.

[0073] FIG. 8 is an exploded perspective view showing a first modification of the power conversion device according to an embodiment. The power conversion device 101A shown in FIG. 8 is a first modification of the above-described power conversion device 101. Note that FIG. 8 omits illustration of the conductive patterns formed on the substrate 40.

[0074] The upper surface 33a of the cooler 30 has recesses 33aa into which the plurality of switching elements 21u, 21v, 21w, 22u, 22v, 22w are respectively inserted. With the plurality of switching elements 21u, etc. inserted into the recesses 33aa respectively, the substrate 40 is fixed to the cooler 30, so that the plurality of switching elements 21u, etc. can be efficiently cooled from around them. The recesses 33aa may be holes or grooves. In the configuration of FIG. 5, the cooling method of the switching element is one-sided cooling that exchanges heat with only one side in contact with the cooler 30. On the other hand, in the configuration of FIG. 8, since the switching elements are inserted into the cooler 30, the cooling method of the switching element is two-sided cooling that exchanges heat with at least both sides. Therefore, compared with the configuration of FIG. 5, the configuration of FIG. 8 has improved cooling efficiency.

[0075] The plurality of switching elements 21u, etc. shown in FIG. 8 are through-hole mount components with the longitudinal direction in the Z-axis direction, and are electrically joined to the plurality of through-holes 48 formed in the substrate 40 by soldering or the like. The plurality of switching elements 21u, etc. may be surface mount components with the longitudinal direction in the Z-axis direction as shown in FIG. 9.

[0076] FIG. 10 is an exploded perspective view showing a second modification of the power conversion device according to an embodiment. FIG. 11 is a front view showing a second modification of the power conversion device according to an embodiment. The power conversion device 101B shown in FIGS. 10 and 11 is a second modification of the above-described power conversion device 101. Note that FIG. 10 omits illustration of the second positive electrode patterns 23up, etc. formed on the substrate 40. Also, FIG. 10 shows a form in which the power connector 7 and the output connector 2 are integral members, but they may be separate members.

[0077] The connector 10 is a member in which the power connector 7 and the output connector 2 are integrated, and is mounted on the lower surface 46 side of the substrate 40. The connector 10 has a plurality of terminals that are electrically connected to the conductive patterns of a plurality of wirings formed on the substrate 40. The connector 10 has a positive terminal 8p, a negative terminal 9n, and output terminals 2u, 2v, 2w, and also has a plurality of connection terminals 10p, 10n, 10u, 10v, 10w. The plurality of connection terminals 10p, 10n, 10u, 10v, 10w are electrodes that are electrically connected to the positive terminal 8p, the negative terminal 9n, and the output terminals 2u, 2v, 2w, respectively, and are provided on a connector surface 10a facing the positive Z-axis direction of the connector 10.

[0078] The connector 10 and the substrate 40 are fixed to each other by a first fixing member. In this example, they are fastened to each other by fastening members 44 such as a plurality of screws. The plurality of connection terminals 10p, 10n, 10u, 10v, 10w are electrically connected to the conductive patterns of the plurality of wirings via a conductive first fixing member such as the fastening member 44. Thereby, the mechanical connection and the electrical connection can be shared by the conductive first fixing member. The plurality of connection terminals 10p, 10n, 10u, 10v, 10w are electrically connected to a first positive pattern 80p, a first negative pattern 90p, a U-phase pattern 27up, a V-phase pattern 27vp, and a W-phase pattern 27wp, respectively.

[0079] For example, a male screw fastening member 44 is inserted into a plurality of female screw holes formed in each of the plurality of connection terminals 10p, 10n, 10u, 10v, 10w and a plurality of through holes formed in the substrate 40. Thereby, the connector 10 and the substrate 40 are fastened, and the plurality of connection terminals 10p, 10n, 10u, 10v, 10w are electrically connected to the first positive pattern 80p, the first negative pattern 90p, the U-phase pattern 27up, the V-phase pattern 27vp, and the W-phase pattern 27wp, respectively. Note that the plurality of connection terminals 10p, 10n, 10u, 10v, 10w may be electrically connected to a plurality of lands (not shown) formed on the lower surface 46 of the substrate 40.

[0080] The substrate 40 and the capacitor 56 are fixed to each other by a second fixing member, and in this example, they are fastened to each other by fastening members 43 such as a plurality of screws. The first capacitor electrode 51 and the second capacitor electrode 52 are electrically connected to the power supply wiring patterns of the plurality of second power supply wirings via a conductive second fixing member such as the fastening member 43. Thereby, both the mechanical connection and the electrical connection can be shared by the conductive second fixing member. The first capacitor electrode 51 is electrically connected to the first substrate electrode 41 formed on the substrate 40, and the second capacitor electrode 52 is electrically connected to the second substrate electrode 42 formed on the substrate 40. The first substrate electrode 41 is electrically connected to the conductive power supply wiring pattern forming the second positive wiring 57, and the second substrate electrode 42 is electrically connected to the conductive power supply wiring pattern forming the second negative wiring 58.

[0081] For example, a male screw fastening member 43 is inserted into a female screw hole formed in the first capacitor electrode 51 and a substrate through hole formed in the first substrate electrode 41. Thereby, the substrate 40 and the capacitor 56 are fastened, and the first capacitor electrode 51 and the first substrate electrode 41 are electrically connected. Similarly, a male screw fastening member 43 is inserted into a female screw hole formed in the second capacitor electrode 52 and a substrate through hole formed in the second substrate electrode 42. Thereby, the substrate 40 and the capacitor 56 are fastened, and the second capacitor electrode 52 and the second substrate electrode 42 are electrically connected. Note that the first capacitor electrode 51 and the second capacitor electrode 52 may be electrically connected to a plurality of lands (not shown) formed on the lower surface 46 of the substrate 40.

[0082] Also, although not shown, the first positive pattern 80p and the first negative pattern 90p may also be electrically connected to a plurality of electrodes provided on the capacitor 56 in the same manner as the first capacitor electrode 51 and the second capacitor electrode 52, via a second fixing member, in the same manner as the second positive wiring 57 and the second negative wiring 58. Thereby, both the mechanical connection and the electrical connection can be shared by the conductive second fixing member.

[0083] FIG. 12 is an exploded perspective view showing a third modification of the power conversion device in one embodiment. The power conversion device 101C shown in FIG. 12 is a third modification of the above-described power conversion device 101. The connector 11 in the third modification has a plurality of lead terminals 11p, 11n, 11u, 11v, 11w instead of the plurality of connection terminals 10p, 10n, 10u, 10v, 10w of the connector 10 in the second modification.

[0084] The plurality of lead terminals 11p, 11n, 11u, 11v, 11w are fixed to a plurality of through holes (not shown) formed in the substrate 40 by a conductive first fixing member such as solder, whereby the connector 11 and the substrate 40 are fixed to each other.

[0085] FIG. 13 is a front view showing a fourth modification of the power conversion device in one embodiment. The power conversion device 101D shown in FIG. 13 is a fourth modification of the above-described power conversion device 101. In the fourth modification, the plurality of connection terminals 10p, 10n, 10u, 10v, 10w are electrically connected to the first positive electrode pattern 80p, the first negative electrode pattern 90p, the U-phase pattern 27up, the V-phase pattern 27vp, and the W-phase pattern 27wp, respectively, via a plurality of conductive bus bars 12. One end of each of the plurality of bus bars 12 is fastened to the plurality of connection terminals 10p, 10n, 10u, 10v, 10w via fastening members 45 such as a plurality of screws. The other end of each of the plurality of bus bars 12 is electrically connected to the first positive electrode pattern 80p, the first negative electrode pattern 90p, the U-phase pattern 27up, the V-phase pattern 27vp, and the W-phase pattern 27wp via conductive fastening members 44 (an example of the first fixing member) such as a plurality of screws.

[0086] As described above, the power conversion device has been described according to the embodiments, but the present invention is not limited to the above embodiments. Various modifications and improvements such as combinations or substitutions with part or all of other embodiments are possible within the scope of the present invention.

[0087] For example, the power conversion device according to the present disclosure is not limited to an inverter that generates three-phase alternating current, and may be an inverter that generates alternating current other than three-phase.

[0088] Moreover, the power conversion device according to the present disclosure is not limited to an inverter that converts direct current into alternating current, and may also be a converter that converts direct current into direct current. Specific examples thereof include a boost converter that boosts an input voltage and outputs it, a buck converter that steps down an input voltage and outputs it, and a buck-boost converter that boosts or steps down an input voltage and outputs it.

[0089] There may be a request from an end user or the like to change the position of a connection part (for example, a connector) exposed from the housing of the power conversion device. However, if a design change such as a layout change of the internal components of the power conversion device newly occurs along with the change in the position of the connection part, losses in time and cost due to the new design change will occur. According to the present disclosure, it is possible to provide a power conversion device that can flexibly respond to design changes accompanying a change in the position of the connection part. This application claims priority based on Japanese Patent Application No. 2020-038108 filed on March 5, 2020, and incorporates the entire contents of Japanese Patent Application No. 2020-038108 into this application.

Explanation of Signs

[0090] 1u, 1v, 1w output wiring 2 output connector 2u, 2v, 2w output terminals 6 housing 7 power connector 8p positive terminal 9n negative terminal 10, 11 connectors 12 bus bar 14u, 14v, 14w first control electrode 15u, 15v, 15w second control electrode 16 control board 17 control circuit 18 drive circuit 19 power conversion module 20 power conversion circuit 21u, 21v, 21w, 22u, 22v, 22w switching elements 23u, 23v, 23w first main electrode 23up Second positive electrode pattern 23vp Third positive electrode pattern 23wp Fourth positive electrode pattern 24u, 24v, 24w Fourth main electrode 24up Second negative electrode pattern 24vp Third negative electrode pattern 24wp Fourth negative electrode pattern 25u, 25v, 25w Second main electrode 27up U-phase pattern 27vp V-phase pattern 27wp W-phase pattern 28 Current sensor module 28p Current sensor circuit 28u, 28v, 28w Current sensor 29u, 29v, 29w Third main electrode 30 Cooler 33a Upper surface 33aa Recess 40 Substrate 46 Lower surface 48 Through hole 51 First capacitor electrode 52 Second capacitor electrode 56 Capacitor 56a Capacitor surface 57 Second positive electrode wiring 58 Second negative electrode wiring 80 First positive electrode wiring 80p First positive electrode pattern 83 Positive electrode wiring 90 First negative electrode wiring 90p First negative electrode pattern 93 Negative electrode wiring 100, 101, 101A, 101B, 101C, 101D Power conversion device

Claims

1. A substrate on which a conductive pattern is formed and a plurality of switching elements for power conversion are mounted, and a cooler for cooling the plurality of switching elements, wherein the substrate has a first surface on which the plurality of switching elements are mounted, the cooler faces the first surface, the switching element is a chip-type surface mount component, a power conversion device.

2. A drive circuit for driving at least one of the plurality of switching elements is mounted on the substrate, the power conversion device according to Claim 1.

3. The power conversion device according to Claim 1 or 2, comprising a capacitor located on the first surface side of the substrate. The power conversion device according to Claim 1 or 2.

4. The power conversion device according to Claim 3, wherein the capacitor and the cooler are located on the same plane. The power conversion device according to Claim 3.

Images