WO2015052984A1

WO2015052984A1 - Electrical power converter

Info

Publication number: WO2015052984A1
Application number: PCT/JP2014/070880
Authority: WO
Inventors: 敦明横山; 早川　和宏; 貴也石井; 雅広宮下
Original assignee: 日産自動車株式会社
Priority date: 2013-10-09
Filing date: 2014-08-07
Publication date: 2015-04-16

Abstract

　An inverter (30) in which components of an electrical power conversion circuit including switching elements (31-36) and smoothing capacitors (37-39) are housed in a case (65), and power inputted to input terminals (69, 70) of the electrical power conversion circuit is converted and outputted to output terminals (77-79), wherein a first connecting portion (1C) to which first terminals (43, 44) of the smoothing capacitors and the input terminals (69, 70) are connected and second connecting portions (2C) to which first terminals (60-62) of the switching elements and the output terminals (77-79) are connected are disposed in the upper portion of the case, and a surface (1Fo) opposite a surface (1F) on which the first connecting portions of the smoothing capacitors are provided and a surface (2Fo) opposite to a surface (2F) on which the second connecting portions of the switching elements are provided are present in the lower portion of the case.

Description

Power converter

The present invention relates to a power conversion device.

As an inverter (power conversion device) for supplying power to the SR motor, a smoothing capacitor and IGBT are mounted on a substrate having a water cooling mechanism, and a power conversion circuit is configured by a power supply bus bar to integrate inverter components. Is known (Patent Document 1).

JP-A-11-69840

When this type of power conversion device is applied to power supply and charging of a travel drive motor for an electric vehicle, it must be housed in a housing to protect the components, and the influence of water that has entered the housing is suppressed. Must. However, since the above prior art does not consider such mounting on a vehicle, water that has entered the housing may adversely affect the components of the power conversion device.

The problem to be solved by the present invention is to provide a power conversion device capable of suppressing the influence on the components even when water enters the housing.

The present invention provides a power conversion device in which a component including a switching element and a smoothing capacitor is housed in a housing, and includes at least a first connection part between the smoothing capacitor and the input terminal and a second connection part between the switching element and the output terminal. Arrange the surface on the upper side of the housing and the surface opposite to the first connection portion of the smoothing capacitor and the surface on the opposite side of the second connection portion of the switching element on the lower side of the housing. To solve the above problem.

According to the present invention, when water enters the case, it is concentrated at the bottom of the case, but the first connection part and the second connection part that are affected by water are disposed at least on the upper side of the case. It can suppress that these components contact water.

It is an electric circuit diagram showing a motor control system to which an embodiment of a power conversion device according to the present invention is applied. It is the top view and front view which show the smoothing capacitor module contained in one Embodiment of the power converter device which concerns on this invention. It is the top view and front view which show the switching module contained in one Embodiment of the power converter device which concerns on this invention. It is a top view which shows the inside of the housing | casing of one Embodiment of the power converter device which concerns on this invention. It is a front view which shows the inside of the housing | casing of one Embodiment of the power converter device which concerns on this invention. It is a front view which shows the inside of the housing | casing of other embodiment of the power converter device which concerns on this invention. It is sectional drawing which shows the heat sink of FIG. It is a front view which shows the inside of the housing | casing of further another embodiment of the power converter device which concerns on this invention. It is a front view which shows the inside of the housing | casing of further another embodiment of the power converter device which concerns on this invention.

FIG. 1 is an electric circuit diagram showing an embodiment in which a power control device according to the present invention is embodied as a DC-three-phase AC conversion device (hereinafter referred to as an inverter 30) and applied to a motor control system 1. Although detailed illustration is omitted, the motor control system 1 of the present embodiment can be applied to an AC uninterruptible power supply and the like in addition to a traveling drive device of an electric vehicle. When the motor control system 1 of the present embodiment is applied to an electric vehicle, a hybrid vehicle, and a fuel cell vehicle, the three-phase AC load 20 shown in FIG. 1 corresponds to a travel drive motor, and is constituted by a secondary battery or the like. The DC power source 10 corresponds to a travel drive battery.

The motor control system 1 of this embodiment includes a DC power supply 10, a three-phase AC load 20, and an inverter 30 that converts DC power of the DC power supply 10 into three-phase AC power. The DC power supply 10 can be constituted by, for example, a secondary battery such as a lithium ion battery, a solar battery, a fuel cell, a PFC (Power factor correction) converter, or the like. When the AC load 20 has a regeneration function, the AC power of the AC load 20 may be converted into DC power by the inverter 30 and the DC power supply 10 may be charged.

The inverter 30 includes

upper arm circuits

31, 33, 35,

lower arm circuits

32, 34, 36,

smoothing capacitors

37, 38, 39, and a controller 40. The inverter 30 converts the DC power of the DC power supply 10 into three-phase AC power. And this is supplied to the three-phase AC load 20. The

upper arm circuits

31, 33, and 35 are mainly composed of circuits in which switching elements Q1, Q3, and Q5 as power devices and diodes D1, D3, and D5 are connected in parallel, respectively. The

lower arm circuits

32, 34, and 36 are mainly configured by a circuit in which switching elements Q2, Q4, and Q6 as power devices are connected in parallel with diodes D2, D4, and D6, respectively.

In the present embodiment, three pairs of circuits in which two switching elements Q1, Q2, Q3, Q4, Q5, and Q6 are connected in series are connected between the power supply line P and the power supply line N, so that DC The connection midpoints connected in parallel to the power supply 10 and connecting each pair of switching elements Q1 and Q2, Q3 and Q4, Q5 and Q6, and the three-phase input portion of the three-phase AC load 20 are electrically connected to each other. It is connected. That is, in the inverter 30 of this embodiment, the upper arm circuit 31 and the lower arm circuit 32, the upper arm circuit 33 and the lower arm circuit 34, and the upper arm circuit 35 and the lower arm circuit 36 are connected in series, respectively. The connection intermediate point between the upper arm circuit 31 and the lower arm circuit 32 is connected to the U phase of the AC load 20, the connection intermediate point between the upper arm circuit 33 and the lower arm circuit 34 is connected to the V phase of the AC load 20, A connection intermediate point between the upper arm circuit 35 and the lower arm circuit 36 and the W phase of the AC load 20 are connected.

These upper arm circuits and lower arm circuits 31 to 36 are switching-controlled at a high frequency by the controller 40. The controller 40 alternately turns ON / OFF the upper arm circuit 31 and the lower arm circuit 32 to increase / decrease the ON time ratio and control the output from the inverter 30. The upper arm circuit 31 includes a switching element Q1, a diode D1, and a gate drive circuit. The drain electrode of the switching element Q1 is connected to the cathode terminal of the diode D1, and the source electrode of the switching element Q1 is connected to the anode terminal of the diode D1. Has been. The gate electrode of the switching element Q1 is connected to the controller 40 through a gate drive circuit. The other terminals of the upper arm circuit and the lower arm circuits 32 to 36 are also connected to the controller 40 with the same configuration.

The switching elements Q1 to Q6 of the present embodiment are wide gap semiconductor devices (SiC devices, GaN devices, diamond devices) or Si devices, such as junction field effect transistors (JFETs), MOSFETs or insulated gate bipolars. A transistor (IGBT) can be used. In addition, as each of the diodes D1 to D6 of the present embodiment, for example, FRD (high-speed rectifying element, Fast Recovery Diode), SBD (Schottky barrier diode, Schottky Barrier Diode), or the like can be used.

The inverter 30 of this embodiment has three

smoothing capacitors

37, 38, and 39, and each of the smoothing capacitors 37 to 39 is paired between the power supply line P and the power supply line N and the lower arm circuit and the lower arm. The

circuits

31 and 32, 33 and 34, and 35 and 36 are connected in parallel, respectively. In the inverter 30 of this embodiment, three smoothing capacitors 37 to 39 are provided, one for each of the three upper arm circuits and the

lower arm circuits

31 and 32, 33 and 34, and 35 and 36 that form a pair. However, one or two smoothing capacitors may be provided by increasing the capacitor capacity, or four or more smoothing capacitors may be provided by reducing the capacitor capacity. It can select suitably according to the layout of the inverter 30 mentioned later.

The above is the electrical configuration of the inverter 30 of the present embodiment. Next, the outer shape, layout, and other mechanical structures of the components of the inverter 30 will be described. In the following description, when a direction such as “up and down” or “vertical” is indicated, it means a direction in a state where the inverter 30 of this embodiment is mounted on a vehicle or an uninterruptible power supply. 2A is a plan view (upper view) and a front view (lower view) showing the smoothing capacitor module 41 of the present embodiment, and FIG. 2B is a plan view (upper view) and a front view (lower view) of the switching module 52 of the present embodiment. It is. 2A and 2B, the main bodies of the smoothing capacitors 37 to 39, the main bodies of the switching elements Q1 to Q6, the main bodies of the diodes D1 to D6, and the internal wiring, which are components, are external to the

package

42 and 53. Is not visible, but is shown in a perspective view using a circuit symbol for convenience in each plan view.

The smoothing capacitor module 41 of the present embodiment incorporates three

smoothing capacitors

37, 38, and 39 as shown in FIG. 2A, and has a substantially rectangular parallelepiped packaging with wiring as shown in FIG. 2A inside. Consists of the body. As shown in the figure, at the left end of the upper surface of the package 42, a P terminal portion 43 connected to the plus terminal of the DC power source 10 and an N terminal portion 44 connected to the minus terminal of the DC power source 10 are provided. Is provided so as to be exposed to the outside of the package 42. Further, on the right end portion of the upper surface of the package 42, the capacitor side for connecting the smoothing

capacitors

37, 38, and 39 to the upper and

lower arm circuits

31 and 32, 33 and 34, 35 and 36 which form a pair. High voltage connection terminal portions 45 to 50 are provided so as to be exposed to the outside of the package 42. Also, a mounting portion 51 is provided at the bottom of the package 42, and the smoothing capacitor module 41 is fixed to a housing 65 described later by inserting and tightening a bolt through the through hole.

As shown in FIG. 2B, the switching module 52 of the present embodiment incorporates six switching elements Q1 to Q6 and six diodes D1 to D6, and has a substantially rectangular parallelepiped shape with wiring as shown in FIG. 2B inside. It consists of a packaging body. As shown in the figure, the upper and

lower arm circuits

31 and 32, 33 and 34, 35 and 36, and smoothing

capacitors

37, 38 and 39, which are paired, are formed at the left end of the upper surface of the package 53. Switching-side high-voltage connection terminal portions 54 to 59 for connecting are connected to the outside of the package 53. Further, at the right end of the upper surface of the package 53, a U terminal portion 60 connected to the U phase of the AC load 20, a V terminal portion 61 connected to the V phase of the AC load 20, and a W phase of the AC load 20. And a W terminal portion 62 to be connected to the outside of the package 53 so as to be exposed to the outside. Further, a mounting portion 63 is provided at the bottom of the package 53, and the switching module 52 is fixed to a housing 65 to be described later by inserting and tightening a bolt through the through hole. Reference numeral 64 indicated by a two-dot chain line in FIG. 2B is a heat sink for releasing heat generated in the switching module 52.

Note that capacitor-side high-voltage connection terminal portions 45 to 50 provided at the right end portion of the upper surface of the smoothing capacitor module 41, and switching-side high-voltage connection terminal portions 54 to 59 provided at the left end portion of the upper surface of the switching module 52; Are connected in the configuration of the electric circuit diagram shown in FIG. 1, but in this embodiment, the capacitor-side high-voltage connection terminal portions 45 to 50 and the switching-side high-voltage connection terminal portions 54 to 59 formed at substantially opposite positions, that is, 45 and 54, 46 and 55, 47 and 56, 48 and 57, 49 and 58, and 50 and 59, the arrangement position of each high-voltage connection terminal portion is considered.

The above configuration is common to the embodiments of the present invention, and the arrangement structure inside the housing 65 described below is different for each embodiment, and will be described for each embodiment.

<< First Embodiment >>
FIG. 3 is a plan view showing the inside of the casing 65 of the inverter 30 of the present embodiment, and FIG. 4 is a front view of the same. In the inverter 30 of this embodiment, the smoothing capacitor module 41 and the switching module 52 described above are accommodated in a casing 65, and

circuit boards

66 and 67 such as a printed circuit board PCB and a printed wiring board PWB constituting the controller 40 are also provided in the casing. Housed in the body 65. As shown in FIGS. 3 and 4, the housing 65 of the present embodiment has a substantially rectangular parallelepiped shape, and includes a housing body 65 a that forms the lower portion of the housing 65, and a lid body 65 b that forms the upper portion of the housing 65. The flange portion of the casing body 65a and the flange portion of the lid body 65b are combined and tightened with bolts, nuts, or the like to close the inside. The casing 65 is made of an insulating material.

As shown in FIG. 4, the smoothing capacitor module 41 and the switching module 52 described above are fixed to the bottom of the housing body 65 a. Although the fixing structure to these housing main bodies 65a is not particularly limited, in the present embodiment, the smoothing capacitor module 41 is attached to each boss portion 68 constituting an attachment portion provided at an appropriate position on the bottom surface of the housing main body 65a. The attachment part 51 and the attachment part 63 of the switching module are aligned and fixed by bolting. As a result, the height of the boss portion 68 makes the space between the bottom surface of the package 42 of the smoothing capacitor module 41 and the bottom surface of the housing body 65a, and between the bottom surface of the package 53 of the switching module 52 and the bottom surface of the housing body 65a. A space is formed in each. The smoothing capacitor module 41 and the switching module 52 may be fixed to a rigid substrate, and this substrate may be fixed to the housing body 65a.

As shown in FIGS. 3 and 4, the bus terminal 69 for connecting to the connector (not shown) of the DC power source 10 shown in FIG. 1 is connected to each of the P terminal portion 43 and the N terminal portion 44 of the smoothing capacitor module 41. , 70 are fixed by bolts or the like. Also, six bus bars 71 for electrically connecting the capacitor-side high-voltage connection terminal portions 45 to 50 and the switching-side high-voltage connection terminal portions 54 to 59 of the switching module 52 within the housing 65 are provided. 76 are fixed by bolts or the like. Further, bus bars 77 to 79 for connecting each of the U terminal portion 60, the V terminal portion 61, and the W terminal portion 62 of the switching module 52 to a connector (not shown) of the AC load 20 are fixed with bolts or the like. Has been. Bus bars 69 and 70 for connecting to the DC power source 10 and

bus bars

77, 78 and 79 for connecting to the AC load 20 are provided so as to be exposed from the inside of the housing 65 to the outside. .

Circuit boards

66 and 67 on which various drive circuit components for driving the switching elements Q1 to Q6 are mounted are also accommodated in the housing 65. These

circuit boards

66 and 67 constitute the controller 40 shown in FIG. As shown in FIGS. 3 and 4, the

circuit boards

66 and 67 of the present embodiment are divided into two parts with sizes to be placed on the upper surfaces of the smoothing capacitor module 41 and the switching module 52, and the boss part 80 is interposed therebetween. The upper surfaces of the smoothing capacitor module 41 and the switching module 52 are fixed by bolts or the like. Further,

circuit terminals

81 and 82 for connecting the wiring circuits of the

circuit boards

66 and 67 are provided on the upper surfaces of the

circuit boards

66 and 67, and these

circuit terminals

81 and 82 are electrically connected by a wire harness 83. ing.

Further, as shown in FIG. 4, an input / output terminal 84 for transmitting / receiving command signals and detection signals to / from the controller 40 is provided on the upper surface of one circuit board 66, and the lid 65 b of the housing 65 is provided. The connector 85 and the wire harness 86 provided on the upper surface are electrically connected. When the connector of the vehicle controller or the controller of the uninterruptible power supply device (not shown) is connected to the connector 85, the inverter 30 of this embodiment is controlled. In the present embodiment, the connector 85 is provided on the upper surface of the lid body 65b. However, the connector 85 may be provided on the side surface of the lid body 65b or the side surface of the housing body 65a.

As shown in FIG. 4, in the inverter 30 of the present embodiment, an air-cooled heat sink 64 is provided on the lower surface of the switching module 52. The heat sink 64 is fixed to the lower surface of the switching module 52 by a bolt or the like (not shown), and the heat radiating portion 64a is provided so as to be exposed to the outside through an opening 87 formed on the bottom surface of the housing main body 65a. The heat generated by the switching module 52 can be removed by the heat radiating portion 64a exchanging heat (dissipating heat) with the outside air. Although not shown, a seal member is provided between the opening 87 formed at the bottom of the housing main body 65a and the heat sink 64 so that water and dust from the outside do not enter.

As described above, the inverter 30 according to the first embodiment includes the connection portion between the P terminal portion 43 of the smoothing capacitor module 41 and the bus bar 69 connected to the DC power supply 10, and the N terminal portion 44 of the smoothing capacitor module 41. Connection portions with the bus bar 70 connected to the DC power supply 10 (these connection portions are referred to as first connection portions 1C) are arranged on the upper side of the housing 65. In addition, a connection portion between the U terminal portion 60 of the switching module 52 and the bus bar 77 connected to the U phase of the AC load 20, a bus bar 78 connected to the V terminal portion 61 of the switching module 52 and the V phase of the AC load 20, And the connection portion between the W terminal portion 62 of the switching module 52 and the bus bar 79 connected to the W phase of the AC load 20 (these connection portions are referred to as the second connection portion 2C) It is arranged in the part. The upper portion of the housing 65 in the present embodiment is 1/3 or more from the bottom of the height dimension of the housing 65 in the vertical direction, as indicated by the alternate long and short dash line in the side view of FIG. An area of 1/2 or more, more preferably 2/3 or more is meant.

On the other hand, the inverter 30 according to the first embodiment is provided with a first connection portion 1 C that is a connection portion between the P terminal portion 43 and the N terminal portion 44 of the smoothing capacitor module 41 and the bus bars 69 and 70. The surface 1Fo of the smoothing capacitor module 41 on the side opposite to 1F is disposed on the lower side of the housing 65. In other words, the

terminal portions

43 and 44 of the smoothing capacitor module 41 are disposed on the upper side, and the main body of the smoothing capacitor module 41 is disposed on the lower side. Further, switching on the opposite side to the surface 2F on which the second connection portion 2C, which is a connection portion between the U terminal portion 60, the V terminal portion 61 and the W terminal portion 62 of the switching module 52, and the bus bars 77, 78, 79 is provided. The surface 2Fo of the module 52 is also disposed on the lower side of the housing 65. In other words, the terminal portions 60 to 62 of the switching module 52 are arranged on the upper side, and the main body of the switching module 52 is arranged on the lower side. The lower side portion of the casing 65 in the present embodiment refers to an area other than the upper side portion of the casing 65 described above, and the casing in the vertical direction as indicated by a dashed line in the side view of FIG. The area below the height dimension of 65 is 1/3 or less, preferably 1/2 or less, more preferably 2/3 or less.

In addition, the inverter 30 according to the first embodiment includes a connection portion between the capacitor-side high-voltage connection terminal portions 45 to 50 of the smoothing capacitor module 41 and the switching-side high-voltage connection terminal portions 54 to 59 of the switching module 52 (these connection portions are connected to each other). The third connection portion 3 C) is also disposed on the upper portion of the housing 65. Further, in the inverter 30 according to the first embodiment, the

circuit boards

66 and 67 divided into two are arranged on the upper side in the vertical direction above the upper surfaces of the smoothing capacitor module 41 and the switching module 52.

From the above, in the inverter 30 according to the first embodiment, when water enters the housing 65 due to some cause such as the usage environment of the inverter 30, the water is collected at the bottom of the housing 65. In the present embodiment, the first connection portion 1C, the second connection portion 2C, the third connection portion 3C, and the

circuit boards

66 and 67 through which high-voltage power from the DC power supply 10 flows are arranged on the upper portion of the housing 65. It can suppress that these high voltage electric power parts contact water. When the inverter 30 is assembled, the smoothing capacitor module 41 and the switching module 52 are assembled to the housing 65, the bus bars 69 to 79 are assembled, the

circuit boards

66 and 67 are then assembled, and then the wire harnesses 83 and 86 are assembled. By adopting the process of assembling the components in order from the bottom, the assembling workability can be remarkably improved.

<< Second Embodiment >>
FIG. 5 is a front view showing the inside of the housing 65 of the inverter 30 (power converter) according to the second embodiment of the present invention, and FIG. 6 is a cross-sectional view showing the heat sink 64 of FIG. The inverter 30 according to the second embodiment is different from the air-cooled inverter 30 according to the first embodiment shown in FIG. Since the other configuration is the same as that of the first embodiment, the description of the configuration is incorporated herein.

FIG. 6 is an exploded cross-sectional view showing the water-cooled heat sink 64 of the present embodiment. The heat sink 64 of the present embodiment has a jacket lid 64b in which a heat radiating portion 64a is formed on the lower surface of a flat plate member and an upper surface opened. A cooling jacket 64c having a bottom surface. Although the detailed illustration is omitted in the cross-sectional view of FIG. 6, the heat radiating portion 64a formed on the jacket lid 64b is composed of fins meandering along the lower surface of the jacket lid 64b, and from the state shown in FIG. By covering and fixing the jacket lid 64b on the cooling jacket 64c, the cooling water flow path 64d is formed in cooperation with the side surface and the bottom surface of the cooling jacket 64c. One end of the cooling water channel 64d of the cooling jacket 64c is provided with an opening for sucking the cooling water flowing through the cooling water channel, and the other end of the cooling water channel 64d returns the sucked cooling water to the cooling water channel. An opening is provided. Then, as shown in FIG. 5, the cooling water is sucked from the opening at one end of the cooling water flow path by the circulation pump 88 and is circulated to the other opening. Thus, since the heat sink 64 of this embodiment is a water cooling type, the switching module 52 can be sufficiently cooled even if the vehicle stops and the air cooling capability is low.

However, when the water-cooled heat sink 64 is accommodated in the housing 65 of the inverter 30 as shown in FIG. 5, when cooling water flowing through the cooling water flow path 64 d leaks into the housing 65, the components of the inverter May be adversely affected. For this reason, in the water-cooled heat sink 64 of this embodiment, a seal portion 89 including a gasket such as FIPG (Formed in place gasket) or a rubber gasket is provided on the joint surface between the jacket lid 64b and the cooling jacket 64c. Yes. In the inverter 30 of the present embodiment, the seal portion 89 for stopping the cooling water that leaks into the housing 65 is disposed on the lower side of the housing 65.

Therefore, in the inverter 30 according to the second embodiment, when the cooling water of the heat sink 64 leaks into the housing 65 due to some cause such as the usage environment of the inverter 30, the water is collected at the bottom of the housing 65. In the present embodiment, the seal portion 89 is disposed on the lower side of the housing 65, and the first connection portion 1 C, the second connection portion 2 C, and the third connection portion 3 C through which high-voltage power from the DC power supply 10 flows are the housing 65. Since it is arrange | positioned at an upper part, it can suppress that these high voltage electric power parts contact water.

<< Third Embodiment >>
FIG. 7 is a front view showing the inside of the housing 65 of the inverter 30 (power converter) according to the third embodiment of the present invention. The inverter 30 according to the third embodiment is different from the inverter 30 according to the first embodiment shown in FIG. 4 in that the drainage portion 90 is provided at the bottom of the housing 65. Since the other configuration is the same as that of the first embodiment, the description of the configuration is incorporated herein. In FIG. 7, the boss 68 provided at the bottom of the rightmost housing 65 and the attachment 63 of the switching module 52 are different from the drain 90 described later in a direction perpendicular to the paper surface of FIG. Since it is provided at the position, it is indicated by a dotted line.

In the inverter 30 of the present embodiment, a drain pipe having a L-shaped cross section is attached to the lowermost surface of the bottom (bottom) of the casing 65, and this constitutes the drain 90. When the bottom surface of the housing 65 is a completely flat plate, the drainage part 90 can be provided at an arbitrary part. Further, a partial lowermost surface may be formed on the bottom surface of the housing 65, and the drainage portion 90 may be provided here. The drainage unit 90 of the present embodiment is disposed on the lower side of the housing 65.

Thus, in the inverter 30 according to the third embodiment, when water enters the housing 65 due to some cause such as the usage environment of the inverter 30, the water is collected at the bottom of the housing 65 and is collected from the drainage section 90. In addition, in this embodiment, the drainage portion 90 is disposed on the bottom surface of the lower portion of the housing 65, and the first connection portion 1C, the second connection portion 2C, and the second connection portion through which high-voltage power from the DC power supply 10 flows. Since the three connecting portions 3C are arranged on the upper side of the housing 65, it is possible to suppress these high-voltage power portions from coming into contact with water.

<< 4th Embodiment >>
FIG. 8 is a front view showing the inside of the casing 65 of the inverter 30 (power converter) according to the fourth embodiment of the present invention, which is compared with the air-cooled inverter 30 according to the first embodiment shown in FIG. Thus, the configuration of the water-cooled heat sink 64 is different from the configuration having the drainage portion 90 at the bottom of the housing 65. Since the other configuration is the same as that of the first embodiment, the description of the configuration is incorporated herein. In FIG. 8, the boss 68 provided at the bottom of the rightmost housing 65 and the mounting part 63 of the switching module 52 are different from the drain part 90 described later in the direction perpendicular to the paper surface of FIG. Since it is provided at the position, it is indicated by a dotted line.

FIG. 6 is an exploded cross-sectional view showing the water-cooled heat sink 64 of the present embodiment, similar to the second embodiment described above. The heat sink 64 of the present embodiment has a heat radiating portion 64a formed on the lower surface of a flat plate member. And a cooling jacket 64c having an open top surface and a bottom surface. Although the detailed illustration is omitted in the cross-sectional view of FIG. 6, the heat radiating portion 64a formed on the jacket lid 64b is composed of fins meandering along the lower surface of the jacket lid 64b, and from the state shown in FIG. By covering and fixing the jacket lid 64b on the cooling jacket 64c, the cooling water flow path 64d is formed in cooperation with the side surface and the bottom surface of the cooling jacket 64c. One end of the cooling water channel 64d of the cooling jacket 64c is provided with an opening for sucking the cooling water flowing through the cooling water channel, and the other end of the cooling water channel 64d returns the sucked cooling water to the cooling water channel. An opening is provided. Then, as shown in FIG. 8, the cooling water is sucked from the opening at one end of the cooling water flow path by the circulation pump 88 and is circulated to the other opening. Thus, since the heat sink 64 of this embodiment is a water cooling type, the switching module 52 can be sufficiently cooled even if the vehicle stops and the air cooling capability is low.

However, when the water-cooled heat sink 64 is accommodated in the housing 65 of the inverter 30 as shown in FIG. 8, the cooling water flowing through the cooling water flow path 64d leaks into the housing 65, and the components of the inverter May be adversely affected. For this reason, in the water-cooled heat sink 64 of this embodiment, a seal portion 89 including a gasket such as FIPG (Formed in place gasket) or a rubber gasket is provided on the joint surface between the jacket lid 64b and the cooling jacket 64c. Yes. In the inverter 30 of the present embodiment, the seal portion 89 for stopping the cooling water that leaks into the housing 65 is disposed on the lower side of the housing 65.

Therefore, in the inverter 30 according to the fourth embodiment, when the cooling water of the heat sink 64 leaks into the casing 65 due to some cause such as the usage environment of the inverter 30, the water is concentrated at the bottom of the casing 65. In the present embodiment, the seal portion 89 is disposed on the lower side of the housing 65, and the first connection portion 1 C, the second connection portion 2 C, and the third connection portion 3 C through which high-voltage power from the DC power supply 10 flows are the housing 65. Since it is arrange | positioned at an upper part, it can suppress that these high voltage electric power parts contact water.

Further, in the inverter 30 of the present embodiment, a drain pipe having a L-shaped cross section is attached to the lowermost surface of the bottom portion (bottom surface) of the housing 65, and this constitutes the drain portion 90. When the bottom surface of the housing 65 is a completely flat plate, the drainage part 90 can be provided at an arbitrary part. Further, a partial lowermost surface may be formed on the bottom surface of the housing 65, and the drainage portion 90 may be provided here. The drainage unit 90 of the present embodiment is disposed on the lower side of the housing 65. In the inverter 30 of the present embodiment, the drainage part 90 is disposed below the seal part 89 in the vertical direction.

As described above, in the inverter 30 according to the fourth embodiment, when water enters the housing 65 due to some cause such as a usage environment of the inverter 30 or when water leaks into the housing 65 from the cooling water flow path 64d. The water is collected at the bottom of the housing 65 and discharged from the drainage unit 90 to the outside. In addition, in the present embodiment, the drainage portion 90 is disposed on the bottom surface of the lower side portion of the casing 65, and the first connection portion 1C, the second connection portion 2C, and the third connection portion 3C through which high-voltage power from the DC power supply 10 flows. Since it is arrange | positioned at the upper part of the housing | casing 65, it can suppress that these high voltage electric power parts contact water.

The bus bars 69, 70 correspond to input terminals according to the present invention, the bus bars 77, 78, 79 correspond to output terminals according to the present invention, and the P terminal portion 43 and the N terminal portion 44 according to the present invention. The U terminal portion 60, the V terminal portion 61 and the W terminal portion 62 correspond to the first terminal of the switching element according to the present invention, and the capacitor side high voltage connection terminal portions 45 to 50 correspond to the first terminal of the capacitor. The switching-side high-voltage connection terminal portions 54 to 59 correspond to the second terminal of the switching element according to the present invention.

DESCRIPTION OF SYMBOLS 1 ... Motor control system 10 ... DC power supply 20 ... AC load 30 ... Inverter (power converter)
31, 33, 35 ...

upper arm circuits

32, 34, 36 ... lower arm circuits Q1-Q6 ... switching elements D1-D6 ...

diodes

37, 38, 39 ... smoothing capacitor 40 ... controller 41 ... smoothing capacitor module 42 ... package 43 ... P terminal portion 44 ... N terminal portion 45 to 50 ... Capacitor side high voltage connection terminal portion 51 ... Mounting portion 52 ... Switching module 53 ... Package 54 to 59 ... Switching side high voltage connection terminal portion 60 ... U terminal portion 61 ... V terminal portion 62 ... W terminal part 63 ... Mounting part 64 ... Heat sink 64a ... Heat radiation part 64b ... Jack cover 64c ... Cooling jacket 64d ... Cooling water flow path 65 ... Case 65a ... Case body 65b ...

Cover body

66, 67 ... Circuit board 68 ... Boss Portions 69 to 79: Bus bar 80 ...

Boss portions

81, 82 ... Circuit terminals 83 ... Wire harness 84 ... In / out Terminal 85 ... Connector 86 ... Wire harness 87 ... Opening part 88 ... Circulating pump 89 ... Seal part 90 ... Drainage part 1C ... First connection part 2C ... Second connection part 3C ... Third connection part 1F ... First connection part 1C Provided surface 1Fo… Surface 2F opposite to surface 1F… Surface 2Fo provided with second connecting portion 2C… Surface opposite to surface 2F

Claims

In a power conversion device in which components of a power conversion circuit including a switching element and a smoothing capacitor are housed in a housing, and the power input to the input terminal of the power conversion circuit is converted and output to the output terminal.
The first connection part in which the first terminal of the smoothing capacitor and the input terminal are connected, and the second connection part in which the first terminal of the switching element and the output terminal are connected are the upper part of the housing. Placed in
The surface of the smoothing capacitor opposite to the surface provided with the first connection portion and the surface of the switching element opposite to the surface provided with the second connection portion are the lower side of the housing The power converter arranged in the section.
The power conversion device according to claim 1, wherein the third connection portion, to which the second terminal of the smoothing capacitor and the second terminal of the switching element are connected, is disposed on an upper portion of the casing.
The component of the power conversion circuit includes a circuit board on which a drive circuit component for driving the switching element is mounted,
The power converter according to claim 1, wherein the circuit board is disposed on the upper portion in a vertically upward direction from the smoothing capacitor and the switching element.
A cooling water flow path through which the cooling water flows and a seal portion for stopping leakage of the cooling water from the cooling water flow path, further comprising a heat sink for cooling the switching element,
The power conversion device according to any one of claims 1 to 3, wherein the seal portion is disposed on a lower side portion of the casing.
A drainage part for discharging water that has entered the inside of the housing to the outside;
The power converter according to claim 4, wherein the drainage unit is disposed on a lower side portion of the housing.
The power converter according to claim 5, wherein the drainage unit is disposed below the seal unit in a vertical direction.