Power conversion device

Abstract

To provide a power conversion device in which a DC-DC converter unit can be easily replaced even when the power conversion device is mounted on a load.SOLUTION: A power conversion device 100 is placed on a load 210 and supplies power to a load 210. The power conversion device 100 includes an inverter unit 10 that converts DC power input from a DC power source 200 into AC power and supplies the AC power to the load 210, and a DC-DC converter unit 30 that converts the voltage of the DC power into a different voltage. The inverter unit 10 and the DC-DC converter unit 30 are stacked in this order from the load 210 side.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a power conversion device, and more particularly to a power conversion device including a DC-DC converter unit. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a power conversion device including a DC-DC converter unit is known (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses a power conversion device including an inverter device, a DC-DC converter (a direct current-direct current converter section), and a housing that houses the inverter device and the DC-DC converter. The inverter device includes semiconductor modules that configure an upper arm and a lower arm. The DC-DC converter includes a MOSFET and a high-voltage circuit board on which the MOSFET is mounted. In the above-mentioned Patent Document 1, the DC-DC converter and the inverter device are stacked in this order from the bottom inside the housing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2015 / 163143 Summary of the Invention [Problem to be solved by the invention]

[0005] In the power conversion device described in the above Patent Document 1, the DC-DC converter is a part that is periodically replaced. When the power conversion device of the above Patent Document 1 is placed above a load, the DC-DC converter is sandwiched between the load and the inverter device. This causes a problem in that the DC-DC converter (DC-DC converter unit) cannot be easily replaced.

[0006] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide a power conversion device in which the DC-DC converter unit can be easily replaced even when the power conversion device is placed on a load. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, a power conversion device according to one aspect of the present invention is a power conversion device that is placed on a load and supplies power to the load, and includes an inverter unit that converts DC power input from a DC power source into AC power and supplies it to the load, and a DC-DC converter unit that converts the voltage of the DC power into a different voltage, and the inverter unit and the DC-DC converter unit are stacked in this order from the load side.

[0008] In the power conversion device according to one aspect of the present invention, as described above, the inverter unit and the DC-DC converter unit are stacked in this order from the load side, so that even when the power conversion device is placed on the load, the DC-DC converter unit is disposed on the opposite side to the load, making it easy to replace the DC-DC converter unit.

[0009] In the power conversion device according to the above aspect, preferably, the power conversion device further includes a housing that houses the inverter unit and the DC-DC converter unit, the housing having an opening on the side opposite to the load, and the DC-DC converter unit being exposed from the opening of the housing. Thus, even when the inverter unit and the DC-DC converter unit are housed in the housing, the DC-DC converter unit is exposed from the opening of the housing, making it easy to replace the DC-DC converter unit.

[0010] In this case, the housing is preferably fixed to the load by a fastening member, whereby even when the housing is fixed to the load by the fastening member, the DC-DC converter unit is exposed from the opening of the housing, making it easy to replace the DC-DC converter unit.

[0011] In the power conversion device according to the aforementioned aspect, the load preferably includes a motor for an electric vehicle. This makes it possible to easily replace the DC-DC converter unit even when the power conversion device is mounted on the motor for an electric vehicle.

[0012] In the power conversion device according to the above aspect, preferably, the power conversion device further includes a base on which the inverter unit and the DC-DC converter unit are arranged, the DC-DC converter unit being arranged on an opposite side of the base from the load. Since the DC-DC converter unit is arranged on the opposite side of the base from the load, even when the DC-DC converter unit is arranged on the base, the DC-DC converter unit can be easily replaced.

[0013] In this case, the DC-DC converter unit is preferably fixed to the base unit by fastening members, whereby the DC-DC converter unit can be easily replaced by simply releasing the fastening members.

[0014] The power conversion device according to the above aspect preferably further includes a base unit on which the inverter unit and the DC-DC converter unit are arranged, and a boost converter unit arranged on the input side of the inverter unit for boosting the DC power input from the DC power source and supplying it to the inverter unit, the boost converter unit being arranged on the opposite side of the base unit from the load, whereby even when the power conversion device is placed on the load, the boost converter unit is arranged on the opposite side of the load, making it easy to replace the boost converter unit.

[0015] In this case, the boost converter unit is preferably fixed to the base unit by a fastening member, whereby the boost converter unit can be easily replaced by simply releasing the fastening member. Effect of the Invention

[0016] According to the present invention, as described above, even when the power conversion device is mounted on a load, the DC-DC converter unit can be easily replaced. [Brief description of the drawings]

[0017] [Figure 1] FIG. 2 is a diagram showing a state in which a power conversion device according to an embodiment is mounted on a load. [Diagram 2] 1 is a circuit diagram of a power conversion device according to an embodiment. [Diagram 3] 1 is a perspective view of a power converter (excluding a housing) according to an embodiment; [Figure 4] 1 is an exploded perspective view of a power converter (excluding a housing) according to an embodiment, as viewed from above; [Diagram 5] 2 is a perspective view of a base unit of a power converter according to one embodiment, viewed from below. FIG. [Figure 6] 1 is a side view of a power converter (excluding a housing) according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

[0019] The configuration of a power conversion device 100 according to one embodiment of the present invention will be described with reference to Fig. 1 to Fig. 6. As shown in Fig. 1, the power conversion device 100 is mounted on a load 210. The load 210 includes a motor for an electric vehicle. In this case, the power conversion device 100 is mounted on the vehicle.

[0020] The circuit configuration of the power conversion device 100 will be described with reference to Fig. 2. The power conversion device 100 includes an inverter unit 10. The inverter unit 10 converts DC power input from a DC power source 200 into AC power and supplies the AC power to a load 210. A switch 201 is provided between the power conversion device 100 and the DC power source 200.

[0021] The inverter unit 10 includes a switching element module 11. The switching element module 11 converts DC power into AC power. The switching element module 11 also includes semiconductor switching elements Q1, Q2, and Q3 that form an upper arm, and semiconductor switching elements Q4, Q5, and Q6 that form a lower arm.

[0022] The inverter unit 10 includes a first inverter unit 10a and a second inverter unit 10b. The switching element module 11 includes a first switching element module 11a included in the first inverter unit 10a and a second switching element module 11b included in the second inverter unit 10b. The load 210 includes a first load 210a and a second load 210b. The first inverter unit 10a converts DC power input from the DC power source 200 into AC power and supplies it to the first load 210a. The second inverter unit 10b converts DC power input from the DC power source 200 into AC power and supplies it to the second load 210b.

[0023] The power conversion device 100 includes a boost converter unit 20. The boost converter unit 20 is disposed on the input side of the inverter unit 10. The boost converter unit 20 boosts the DC power input from the DC power source 200 and supplies the boosted power to the inverter unit 10. The boost converter unit 20 includes a boost switching element module 21 and a reactor 22. The boost switching element module 21 includes boost switching elements Q11 and Q12. The boost switching elements Q11 and Q12 form an upper arm and a lower arm, respectively. The boost converter unit 20 also includes a capacitor C1. The reactor 22 is provided between the positive side of the DC power source 200 and a connection point between the boost switching element Q11 and the boost switching element Q12. The capacitor C1 is provided in parallel with the boost switching element Q12.

[0024] The power conversion device 100 includes a capacitor C2 and a resistor R. The capacitor C2 and the resistor R are provided between the boost converter unit 20 and the inverter unit 10. The capacitor C2 and the resistor R are provided in parallel with each other.

[0025] The power conversion device 100 includes a DCDC converter unit 30. The DCDC converter unit 30 converts the voltage of DC power into a different voltage. Specifically, the DCDC converter unit 30 reduces the voltage of the DC power input from the DC power source 200 via the connector 1. The DCDC converter unit 30 also supplies the reduced voltage to the output terminal 2. The DCDC converter unit 30 is an example of the "DC-DC converter unit" in the claims.

[0026] Next, the structure of the power conversion device 100 will be described. As shown in Fig. 1, the power conversion device 100 includes a base unit 50 and a housing 70 in addition to the above-mentioned inverter unit 10, boost converter unit 20, and DCDC converter unit 30. In this embodiment, the inverter unit 10, the base unit 50, and the DCDC converter unit 30 are stacked in this order from the load 210 side. Each component will be specifically described below.

[0027] As shown in Fig. 3, the DC-DC converter unit 30 includes a DC-DC converter element 31 and a DC-DC converter board 32 on which the DC-DC converter element 31 is mounted. The DC-DC converter board 32 has a flat plate shape. The DC-DC converter element 31 mounted on the DC-DC converter board 32 includes a converter switching element 31a, a transformer 31b, a resonant reactor 31c, and a smoothing reactor 31d. The converter switching element 31a is provided on the back side (Z2 side) of the DC-DC converter board 32. The transformer 31b, the resonant reactor 31c, and the smoothing reactor 31d are provided to penetrate the DC-DC converter board 32.

[0028] As shown in Fig. 2, semiconductor switching elements Q1 to Q6 are housed inside the switching element module 11. The semiconductor switching elements Q1 to Q6 are covered with a housing made of resin, etc. As shown in Fig. 4, the switching element module 11 has a rectangular shape when viewed from a direction perpendicular to the surface of the switching element module 11.

[0029] As shown in Fig. 4, the power conversion device 100 includes a base unit 50. The base unit 50 is flat. The inverter unit 10 and the DC-DC converter unit 30 are disposed on the base unit 50. The base unit 50 is formed of a metal having relatively high thermal conductivity, such as aluminum. The base unit 50 has a rectangular shape when viewed from a direction perpendicular to a front surface 50a (surface on the Z1 side) and a back surface 50b (surface on the Z2 side) of the base unit 50.

[0030] As shown in Fig. 4, the base part 50 includes a cooling flow passage 51. Also, as shown in Fig. 6, the cooling flow passage 51 has a flow passage arranged on the Z1 side in the base part 50, a flow passage arranged on the Z2 side in the base part 50, a flow passage arranged on the Z1 side, and a flow passage arranged on the Z2 side.

[0031] Here, in this embodiment, as shown in FIG. 4, the DCDC converter unit 30 is disposed on the opposite side of the load 210 of the base unit 50. Specifically, the DCDC converter unit 30 is disposed on the surface 50a of the base unit 50 on the Z1 side. The DCDC converter unit 30 is fixed to the base unit 50 by a fastening member 80. Specifically, the DCDC converter unit 30 is attached to a cover portion 53 of the base unit 50 (described later) by the fastening member 80. The cover portion 53 is provided with a boss 53b protruding to the Z1 side. The DCDC converter unit 30 is attached to the boss 53b by the fastening member 80 through a hole portion 32a provided in the DC-DC converter board 32 of the DCDC converter unit 30. For example, a plurality of bosses 53b are provided. In addition, the DC-DC converter board 32 on which the DC-DC converter element 31 is mounted is attached to the base unit 50 so as to be aligned with the surface 50a of the flat base unit 50.

[0032] The first switching element module 11a and the second switching element module 11b are attached to the base part 50 so as to be aligned along the back surface 50b of the flat base part 50. Specifically, the first switching element module 11a and the second switching element module 11b are arranged so as to be adjacent to each other along the long side direction (X direction) of the first switching element module 11a and the second switching element module 11b. By arranging them in this manner, the width of the base part 50 in the Y direction can be shortened, and therefore the power conversion device 100 can be made compact. In addition, the first switching element module 11a and the second switching element module 11b are attached to the base part 50 by fastening members 80.

[0033] The boost converter unit 20 is attached to the base unit 50 so as to be aligned along a surface 50a of the flat base unit 50. Specifically, the boost converter unit 20 is attached to the surface 50a of the base unit 50, which is the side opposite to the load 210. The boost converter unit 20 is also disposed adjacent to the DC-DC converter unit 30 along the longitudinal direction (X direction) of the flat base unit 50.

[0034] Specifically, the boost converter section 20 includes a boost switching element module 21 and a reactor 22. The boost switching element module 21 and the reactor 22 are attached to the base section 50 so as to be aligned with a surface 50a of the flat base section 50. The DC-DC converter board 32, the reactor 22, and the boost switching element module 21 are attached to the base section 50 so as to be aligned with the surface 50a of the flat base section 50 and adjacent to each other. The DC-DC converter board 32, the reactor 22, and the boost switching element module 21 are attached to the surface 50a of the base section 50 in this order.

[0035] In this embodiment, the reactor 22 and the boost switching element module 21 are fixed to the base portion 50 by fastening members 80. Specifically, the reactor 22 is fixed to a hole 53c of the cover portion 53 of the base portion 50 by the fastening members 80 through a hole 22a of the reactor 22. For example, a plurality of holes 22a are provided. The boost switching element module 21 is fixed to a hole 52f of the cooling portion main body 52 of the base portion 50 by the fastening members 80 through a hole 21a of the boost switching element module 21. For example, a plurality of holes 21a are provided.

[0036] As shown in FIG. 4, the base 50 includes a cooling section main body 52 made of a metal in which a cooling flow path 51 is formed, and a lid 53 made of a metal that forms the cooling flow path 51 together with the cooling section main body 52. ​​The lid 53 includes an opening 53a. The cooling section main body 52 also includes openings 52a, 52b, and 52c that open to the Z1 side. As shown in FIG. 5, the cooling section main body 52 also includes openings 52d and 52e that open to the Z2 side. The opening 53a of the lid 53 is covered by the reactor 22. In detail, the reactor 22 includes a reactor main body and a lid for the reactor 22 made of a metal, and the lid for the reactor 22 covers the opening 53a of the lid 53. The openings 52a and 52b are covered by the lid 53. The opening 52c is covered by the boost switching element module 21. In detail, the boost switching element module 21 includes a boost switching element module body and a lid for the boost switching element module 21 made of metal, and the lid for the boost switching element module 21 covers the opening 52c. The openings 52d and 52e are covered by the first switching element module 11a and the second switching element module 11b, respectively. In detail, the first switching element module 11a includes a switching element module 11a body and a lid for the first switching element module 11a made of metal, and the lid for the first switching element module 11a covers the opening 52d. The same applies to the opening 52e.

[0037] In this embodiment, as shown in Fig. 4, the DC-DC converter element 31 includes a converter switching element 31a. The converter switching element 31a is attached to the surface of the DC-DC converter board 32 on the lid portion 53 side (the surface on the Z2 side) so as to be in contact with the lid portion 53 via the heat conductive member 33. That is, the lid portion 53, the heat conductive member 33, and the converter switching element 31a are laminated in this order. Heat generated from the converter switching element 31a is dissipated to the lid portion 53 via the heat conductive member 33. The heat conductive member 33 is made of, for example, a ceramic sheet.

[0038] 6, the cooling liquid flowing out of the cooling flow passage 51 is cooled by dissipating heat by the heat dissipation section 60. The cooling liquid cooled by the heat dissipation section 60 is pumped by the pump 61 and flows back into the cooling flow passage 51. The heat dissipation section 60 includes a heat exchanger and is cooled by external air. The heat dissipation section 60 is, for example, a radiator. The pump 61 may be disposed between the outlet of the cooling flow passage 51 and the heat dissipation section 60, and the cooling liquid before dissipating heat by the heat dissipation section 60 may be pumped by the pump 61. The cooling liquid is, for example, water, antifreeze, or other liquid.

[0039] 6, the inverter unit 10 is disposed on the back surface 50b of the base unit 50, and is cooled by the cooling liquid flowing on the Z2 side of the base unit 50. Specifically, the first switching element module 11a and the second switching element module 11b are disposed on the back surface 50b of the base unit 50, and are cooled by the cooling liquid flowing on the Z2 side of the base unit 50.

[0040] The DC-DC converter unit 30 is disposed on the surface 50a of the base unit 50, and is cooled by the cooling liquid flowing on the Z1 side of the base unit 50. Specifically, the converter switching element 31a, the transformer 31b, the resonant reactor 31c, the smoothing reactor 31d, the boost switching element module 21, and the reactor 22 are disposed on the surface 50a of the base unit 50, and are cooled by the cooling liquid flowing on the Z1 side of the base unit 50.

[0041] In the DC-DC converter unit 30, components are arranged in consideration of the influence of thermal interference from the reactor 22. Specifically, the components are arranged so as to avoid arranging components with low heat resistance among the converter switching element 31a, the transformer 31b, the resonant reactor 31c, and the smoothing reactor 31d on the side close to the reactor.

[0042] In addition to the DC-DC converter element 31, the DCDC converter section 30 also includes components such as fuses, capacitors, and Hall sensor elements, and these components dissipate their heat to the surface 50a of the base section 50 via heat dissipation members.

[0043] At least a part of the DCDC converter unit 30 on the reactor 22 side may be covered with a shielding cover to reduce thermal interference from the reactor 22.

[0044] In addition, the cooling flow path 51 is formed so that the cooling liquid first cools the components having the highest priority based on heat resistance, among the first switching element module 11a, the second switching element module 11b, the converter switching element 31a, the transformer 31b, the resonant reactor 31c, the smoothing reactor 31d, the boost switching element module 21, and the reactor 22.

[0045] In this embodiment, as shown in FIG. 1, the housing 70 accommodates the inverter section 10 and the DCDC converter section 30. Specifically, the housing 70 accommodates the inverter section 10, the boost converter section 20, the base section 50, and the DCDC converter section 30, and the inverter section 10, the base section 50, and the DCDC converter section 30 are stacked in this order in the Z1 direction in the housing 70. In addition, the housing 70 has an opening on the Z1 side, which is the opposite side to the load 210, and the DCDC converter section 30 is exposed from the opening of the housing 70. In addition, the boost switching element module 21 and the reactor 22 of the boost converter section 20 are also exposed from the opening of the housing 70. In addition, the housing 70 is fixed to the load 210 by a fastening member 80. Specifically, the housing 70 is fixed to the load 210 by the fastening member 80 through a hole portion 71 provided on the outer periphery of the housing 70.

[0046] [Effects of this embodiment] In this embodiment, the following effects can be obtained.

[0047] In this embodiment, as described above, the inverter unit 10 and the DCDC converter unit 30 are stacked in this order from the load 210 side. As a result, even when the power conversion device 100 is placed on the load 210, the DCDC converter unit 30 is disposed on the opposite side to the load 210, so that the DCDC converter unit 30 can be easily replaced.

[0048] In this embodiment, as described above, the power conversion device 100 further includes a housing 70 that houses the inverter unit 10 and the DCDC converter unit 30. The housing 70 is open on the side opposite to the load 210, and the DCDC converter unit 30 is exposed from the opening of the housing 70. As a result, even when the inverter unit 10 and the DCDC converter unit 30 are housed in the housing 70, the DCDC converter unit 30 is exposed from the opening of the housing 70, so that the DCDC converter unit 30 can be easily replaced.

[0049] In this embodiment, as described above, the housing 70 is fixed to the load 210 by the fastening member 80. As a result, even when the housing 70 is fixed to the load 210 by the fastening member 80, the DCDC converter unit 30 is exposed from the opening of the housing 70, so that the DCDC converter unit 30 can be easily replaced.

[0050] In this embodiment, as described above, the load 210 includes a motor for an electric vehicle. This makes it possible to easily replace the DC-DC converter unit 30 even when the power conversion device 100 is mounted on the motor for an electric vehicle.

[0051] In this embodiment, as described above, the power conversion device 100 further includes a base unit 50 on which the inverter unit 10 and the DCDC converter unit 30 are arranged. The DCDC converter unit 30 is arranged on the opposite side of the base unit 50 from the load 210. As a result, since the DCDC converter unit 30 is arranged on the opposite side of the base unit 50 from the load 210, even when the DCDC converter unit 30 is arranged on the base unit 50, the DCDC converter unit 30 can be easily replaced.

[0052] In this embodiment, as described above, the DC-DC converter unit 30 is fixed to the base unit 50 by the fastening members 80. This makes it possible to easily replace the DC-DC converter unit 30 by simply releasing the fastening member 80.

[0053] In this embodiment, as described above, the power conversion device 100 further includes the base unit 50 on which the inverter unit 10 and the DCDC converter unit 30 are arranged, and the boost converter unit 20, which is arranged on the input side of the inverter unit 10 and boosts the DC power input from the DC power source 200 and supplies the boosted DC power to the inverter unit 10. The boost converter unit 20 is arranged on the opposite side of the base unit 50 to the load 210. As a result, even when the power conversion device 100 is placed on the load 210, the boost converter unit 20 is arranged on the opposite side of the load 210, so that the boost converter unit 20 can be easily replaced.

[0054] In this embodiment, as described above, the boost converter unit 20 is fixed to the base unit 50 by the fastening members 80. This makes it possible to easily replace the boost converter unit 20 by simply releasing the fastening state of the fastening members 80.

[0055] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims, not by the description of the embodiments above, and further includes all modifications (variations) within the meaning and scope of the claims.

[0056] In the above embodiment, the housing 70 is opened on the side opposite to the load 210 (Z1 side), but the present invention is not limited to this. For example, the side opposite to the load 210 (Z1 side) of the housing 70 may be covered with a lid or the like.

[0057] In the above embodiment, an example has been described in which the housing 70 is fixed to the load 210 by the fastening member 80, but the present invention is not limited to this. For example, the housing 70 may be fixed to the load 210 by being fitted into the load 210.

[0058] In the above embodiment, the power conversion device 100 is mounted on a motor for an electric vehicle, but the present invention is not limited to this. For example, the power conversion device 100 may be mounted on a load other than a motor for an electric vehicle (such as a motor for an industrial machine).

[0059] In the above embodiment, the inverter unit 10 and the DC-DC converter unit 30 are disposed on the base unit 50 having the cooling passage 51, but the present invention is not limited to this. For example, the inverter unit 10 and the DC-DC converter unit 30 may be disposed on a plate member that does not have the cooling passage 51.

[0060] In the above embodiment, the DC-DC converter unit 30 and the boost converter unit 20 are fixed to the base unit 50 by the fastening member 80, but the present invention is not limited to this. For example, the DC-DC converter unit 30 and the boost converter unit 20 may be fixed to the base unit 50 by a thermally conductive adhesive.

[0061] In the above embodiment, the boost converter unit 20 is disposed on the opposite side (Z1 side) of the base unit 50 from the load 210, but the present invention is not limited to this. For example, the boost converter unit 20 may be disposed on the load 210 side (Z2 side) of the base unit 50.

[0062] In the above embodiment, an example is shown in which two first inverter units 10a and two second inverter units 10b are provided, and two first loads 210a and two second loads 210b are provided, but the present invention is not limited to this. For example, one inverter unit and one load may be provided. [Explanation of symbols]

[0063] 10 Inverter section 20 Boost converter section 30 DC / DC converter section (DC / DC converter section) 50 Base 70 Case 80 Fastening members 100 Power conversion device 210 Load 200 DC power supply

Claims

1. A power conversion device that is placed on a load and supplies power to the load, an inverter unit that converts DC power input from a DC power source into AC power and supplies the AC power to the load; a DC-DC converter unit that converts a voltage of the DC power into a different voltage, The power conversion device, wherein the inverter unit and the DC-DC converter unit are stacked in this order from the load side.

2. a housing that houses the inverter unit and the DC-DC converter unit, The housing is open on an opposite side to the load, The power conversion device according to claim 1 , wherein the DC-DC converter unit is exposed through an opening in the housing.

3. The power conversion device according to claim 2 , wherein the housing is fixed to the load by a fastening member.

4. The power conversion apparatus of claim 1 , wherein the load includes a motor for an electric vehicle.

5. a base unit on which the inverter unit and the DC-DC converter unit are disposed, The power conversion device according to claim 1 , wherein the DC-DC converter unit is disposed on an opposite side of the base unit to the load.

6. The power conversion device according to claim 5 , wherein the DC-DC converter unit is fixed to the base unit by a fastening member.

7. a base unit on which the inverter unit and the DC-DC converter unit are disposed; a boost converter unit that is disposed on an input side of the inverter unit and boosts the DC power input from the DC power source and supplies the boosted DC power to the inverter unit, The power conversion device according to claim 1 , wherein the boost converter unit is disposed on an opposite side of the base unit from the load.

8. The power conversion device according to claim 7 , wherein the boost converter unit is fixed to the base unit by a fastening member.

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