Power conversion device, electric vehicle drive device using power conversion device, and electric vehicle drive device operation system

Abstract

In this power conversion device (1), a power module (2), a heat dissipation chamber (5), a refrigerant chamber (6), and an auxiliary component chamber (8) are disposed in order from the upper side, the refrigerant chamber (6) is configured from a recess (9) on the upper side of the auxiliary component chamber (8) and is divided into a low-temperature chamber (61) and a high-temperature chamber (62) with a refrigerant chamber partition wall (11) therebetween, the low-temperature chamber (61) and the high-temperature chamber (62) communicate with the heat dissipation chamber (5) via a communicating portion (12), the low-temperature chamber (61) and the high-temperature chamber (62) are disposed parallel to the long-side direction of a region in which the power module (2) is mounted, and the flow of refrigerant in the heat dissipation chamber (5) is parallel to the short-side direction of the region in which the power module (2) is mounted. Additionally, the state of an electric vehicle drive device that incorporates the power conversion device (1) is notified to a worker through a network.

Description

Power conversion device, electric vehicle drive device using the power conversion device, and electric vehicle drive device operation system

[0001] The present disclosure relates to a power conversion device, an electric vehicle drive device using the power conversion device, and an electric vehicle drive device operation system.

[0002] In power conversion devices used in electric vehicles such as hybrid cars or electric vehicles, efforts have been made to miniaturize main circuit components (such as power modules or capacitors) in order to reduce the mounting area of ​​the components. One possible approach to reducing the mounting area of ​​components is to stack components on top of the area where the smoothing capacitor, a large component of the power conversion device, is mounted. However, this configuration complicates the cooling structure of the smoothing capacitor. Furthermore, to achieve uniform cooling of the power module with low pressure loss, it is necessary to flow cooling water in parallel with the power module, which requires a header of a certain width or more, resulting in a larger mounting area.

[0003] In other words, the premise is that the cross-sectional area of ​​the header must be increased to reduce fluid resistance. In the conventional technology described below (Patent No. 7052447), increasing the cross-sectional area of ​​the header would require increasing the cross-sectional area in the thickness direction of the heat sink. In this case, the thickness of the parts other than the header (fins) would also be unnecessarily increased, resulting in waste. Therefore, it is appropriate to increase the cross-sectional area of ​​the header in the planar direction rather than the thickness direction of the heat sink. However, increasing the cross-sectional area of ​​the header in the planar direction would require expanding the width of the entire device, which would increase the mounting area for components.

[0004] Furthermore, as a challenge associated with miniaturization, a common method of cooling smoothing capacitors, which are heat-generating components with a relatively low heat resistance temperature, is to cool the bus bars connected to the elements using heat dissipation material.However, this method alone is no longer sufficient as the current flowing in power conversion devices increases, requiring a wider range of heat dissipation points.

[0005] In a conventional power conversion device, a cooling water supply channel and a cooling water discharge channel are formed in a capacitor case of a capacitor module formed from a metal material or a synthetic resin, the capacitor case and a power semiconductor cooler are joined in a surface-to-surface contact state, and the cooling water supply channel, the cooling water discharge channel, and the power semiconductor refrigerant flow path are directly connected to circulate the cooling medium (see Patent Document 1).

[0006] Patent No. 7052447

[0007] In the above-mentioned conventional technology, a refrigerant flow path is embedded in the capacitor case to cool the condenser, but the configuration of embedding the flow path in the capacitor case is complicated. Furthermore, it is also important to improve the cooling performance of the power semiconductor elements. The smaller the pressure loss and the higher the heat transfer coefficient, i.e., the higher the ratio (heat transfer coefficient / pressure loss), the higher the performance of the cooler. As shown in Figure 3 (described later), by flowing the cooling water parallel to the short side of the power module, the ratio (heat transfer coefficient / pressure loss) is higher than when the cooling water flows parallel to the long side of the power module.

[0008] However, when cooling water flows parallel to the short sides of the power module, the cross-sectional area of ​​the flow path before and after entering the heat dissipation fin area must be sufficiently large to ensure that the refrigerant is supplied evenly in a direction perpendicular to the refrigerant flow direction, i.e., along the long sides. In the above-mentioned conventional technology, to flow cooling water parallel to the short sides of the power module and ensure that the refrigerant flows evenly, the cross-sectional area of ​​the flow path before and after entering the heat dissipation fin area must be large in the planar direction. In other words, to ensure that the required area of ​​the header portions upstream and downstream of the heat dissipation fin area is large in the planar direction, the device must be expanded in the planar direction. This results in the problem of the cooler becoming larger in the planar direction.

[0009] The present disclosure discloses techniques for solving the above-described problems, and aims to provide a power conversion device that is simple in structure and can cool auxiliary components, is small in size, and has high cooling performance, an electric vehicle drive device that uses this power conversion device, and an electric vehicle drive device operating system.

[0010] The power conversion device of the present disclosure includes a power module for converting electric power, a heat dissipation chamber that stores heat dissipation fins that dissipate heat generated by the power module to a refrigerant, a refrigerant chamber that distributes the refrigerant to the heat dissipation fins and collects the refrigerant, and an auxiliary components chamber that stores auxiliary components that assist in power conversion, wherein the power module, the heat dissipation chamber, the refrigerant chamber, and the auxiliary components chamber are arranged in order from one side to the other in a third direction, the refrigerant chamber is formed by a recess on one side of the auxiliary components chamber in the third direction and is divided into a low-temperature chamber and a high-temperature chamber according to the temperature of the refrigerant flowing across a refrigerant chamber partition wall, the low-temperature chamber and the high-temperature chamber communicate with the radiator chamber via a communication part, the low-temperature chamber and the high-temperature chamber are arranged parallel to the long sides of an area in which the power module is mounted, and the flow of the refrigerant in the radiator chamber is configured parallel to the short sides of the area in which the power module is mounted. Also, the electric vehicle drive device of the present disclosure includes the power conversion device together with a motor and a reduction gear. Furthermore, the electric vehicle drive device operating system of the present disclosure adjusts the amount of the refrigerant flowing to the power conversion device by detecting the temperature of the electric vehicle drive device.

[0011] The power conversion device disclosed herein, the electric vehicle drive device using this power conversion device, and the electric vehicle drive device operation system can provide a power conversion device that is simple in structure, cools auxiliary components, and is small in size and has high cooling performance.

[0012] 1 is a perspective view showing a power converter according to embodiment 1. FIG. 2 is an exploded perspective view showing a power converter according to embodiment 1. FIG. 3 is a cross-sectional view showing the pipe side from the center of the power converter according to embodiment 1. FIG. 4 is an enlarged cross-sectional view showing part A in FIG. 3. FIG. 5 is a cross-sectional view showing the pipe side from the center of the power converter according to embodiment 1. FIG. 6 is an enlarged cross-sectional view showing part B in FIG. 5. FIG. 7 is a schematic view showing a case where a refrigerant is caused to flow parallel to the long side direction of a power module mounting area. FIG. 8 is a schematic view showing a case where a refrigerant is caused to flow when the long side and the short side of the power module mounting area are equal. FIG. 9 is a schematic view showing a case where a refrigerant is caused to flow parallel to the short side of the power module mounting area. FIG. 10 is a plot of pressure loss, heat transfer coefficient, and heat transfer coefficient / pressure loss, with C / D on the horizontal axis and pressure loss, heat transfer coefficient, and heat transfer coefficient / pressure loss on the vertical axis. FIG. 11 is a cross-sectional view showing the upper side from the refrigerant chamber of the power converter according to embodiment 1. FIG. 12 is a schematic view showing heat dissipation fins of the power converter according to embodiment 1. FIG. 13 is a schematic view showing a case where stacked fins are used as heat dissipation fins of the power converter according to embodiment 1. FIG. 14 is a schematic view showing a case where comb-shaped fins are used as the heat dissipation fins of the power converter according to embodiment 1. 15 is a view from the direction T in FIG. 14. FIG. 16 is a cross-sectional view of the power converter according to embodiment 2, looking from the center to the pipe side. FIG. 17 is a cross-sectional view of the power converter according to embodiment 2, looking from the center to the pipe side. FIG. 18 is an exploded perspective view of a power converter according to embodiment 3. FIG. 19 is a cross-sectional view showing a portion cut along the refrigerant inlet / outlet pipes of a power converter according to embodiment 4. FIG. 20 is a cross-sectional view of the power converter according to embodiment 4, looking from the center to the pipe side. FIG. 21 is a perspective view of a power converter according to embodiment 5. FIG. 22 is a plan cross-sectional view taken along a plane intersecting the refrigerant chamber in the power converter according to embodiment 5. FIG. 23 is a perspective view of a power converter according to embodiment 5. FIG. 24 is a plan cross-sectional view of the power converter according to embodiment 5, looking from the plane intersecting the refrigerant chamber. FIG. 25 is a cross-sectional view of the power converter according to embodiment 5, looking from the plane intersecting the refrigerant chamber. FIG. 26 is a cross-sectional view of the power converter according to embodiment 2, looking from the plane intersecting the refrigerant chamber.31A is a side view showing a heat dissipation fin portion of a power converter according to a ninth embodiment. FIG. 31A is a cross-sectional view showing a portion cut at the position indicated by line E-E in FIG. 30, FIG. 31B is a cross-sectional view showing a portion cut at the position indicated by line F-F in FIG. 30, FIG. 31C is a cross-sectional view showing a portion cut at the position indicated by line G-G in FIG. 30, FIG. 31D is a cross-sectional view showing a portion cut at the position indicated by line H-H in FIG. 30, and FIG. 31E is a cross-sectional view showing a portion cut at the position indicated by line I-I in FIG. 30. A diagram showing only the refrigerant portion of the flow path inside the heat dissipation fin in the power converter according to the ninth embodiment. A cross-sectional view showing a heat dissipation fin portion of a power converter according to a tenth embodiment. A cross-sectional view showing a heat dissipation fin portion of a power converter according to a tenth embodiment. A cross-sectional view showing a pipe side from the center of a power converter according to an eleventh embodiment. An exploded perspective view showing a power converter according to a twelfth embodiment. A cross-sectional view showing a pipe side from the center of a power converter according to a twelfth embodiment. 50 is a cross-sectional view showing a portion cut along the refrigerant inlet / outlet pipes of the power converter according to embodiment 12. FIG. 51 is an exploded perspective view showing a power converter according to embodiment 13. FIG. 52 is a cross-sectional view showing the pipe side from the center of the power converter according to embodiment 13. FIG. 53 is a cross-sectional view showing a portion cut along the refrigerant inlet / outlet pipes of the power converter according to embodiment 13. FIG. 54 is an exploded perspective view showing a power converter according to embodiment 14. FIG. 55 is a cross-sectional view showing the pipe side from the center of the power converter according to embodiment 14. FIG. 56 is a cross-sectional view showing the pipe side from the center of the power converter according to embodiment 15. FIG. 57 is a cross-sectional view showing the pipe side from the center of the power converter according to embodiment 16. FIG. 58 is a cross-sectional view showing the pipe side from the center of the power converter according to embodiment 17. FIG. 59 is a perspective view showing the integrally molded auxiliary parts chamber and refrigerant chamber recess of the power converter according to embodiment 18. FIG. 51 is a side view seen from the opening of the integrally molded auxiliary parts chamber and refrigerant chamber recess of the power converter according to embodiment 18. FIG. 52 is a cross-sectional view showing the integrally molded auxiliary parts chamber and refrigerant chamber recess of the power converter according to embodiment 19. FIG. 51 is a side view seen from the R direction of FIG. 50.Fig. 20 is a schematic diagram showing an electric vehicle drive device operation system according to embodiment 20. Fig. 21 is a block diagram showing an example of the hardware configuration of a control device.

[0013] Embodiment 1. This embodiment relates to a power conversion device that converts an input current from DC to AC, or from AC to DC, or converts an input voltage to a different voltage, and an electric vehicle drive device using the same. Embodiment 1 will be described with reference to the drawings. FIG. 1 is a perspective view of the power conversion device according to embodiment 1, FIG. 2 is an exploded perspective view of the same, FIG. 3 is a cross-sectional view of the power conversion device according to embodiment 1 viewed from the center toward the pipe, FIG. 4 is an enlarged cross-sectional view of portion A in FIG. 3, FIG. 5 is a cross-sectional view of the power conversion device according to embodiment 1 viewed from the center toward the pipe, and FIG. 6 is an enlarged cross-sectional view of portion B in FIG. 5. In the drawings, symbols X1 and X2 represent one and the other of a first direction, symbol Y represents a second direction perpendicular to the first directions X1 and X2, and symbols Z1 and Z2 represent one (upper side) and the other (lower side) of a third direction perpendicular to an imaginary plane including the first direction X and the second direction Y.

[0014] The power conversion device 1 according to the first embodiment includes a power module 2 that converts DC power into AC power, a base 4 that transfers heat generated in the power module 2 to heat dissipation fins 3, and heat dissipation fins 3 that dissipate the heat received by the base 4 into a coolant. In Fig. 2, it is assumed that the base 4 is transparent, and the heat dissipation fins 3 are shown attached to the other side of the base 4. The power conversion device 1 further includes a heat dissipation chamber 5 that houses the heat dissipation fins 3 and dissipates heat into the coolant, a coolant chamber 6 that distributes the coolant to the heat dissipation fins 3 and collects it, and an auxiliary parts chamber 8 that houses auxiliary parts 7 that assist in power conversion.

[0015] The power module 2, heat dissipation chamber 5, refrigerant chamber 6, and auxiliary component chamber 8 are arranged in this order from the top in the third direction. As shown in FIG. 3 , the refrigerant chamber 6 is formed by a space surrounded by a recess 9 on the top side of the auxiliary component chamber 8 in the third direction and a refrigerant chamber partition wall 10 that contacts the bottom surface (bottom side in the third direction) of the refrigerant chamber 5. Alternatively, as shown in FIG. 5 , it is configured as a space integrated with the refrigerant chamber 5. The refrigerant chamber 6 is divided into two chambers, a low-temperature chamber 61 and a high-temperature chamber 62, depending on the temperature of the refrigerant flowing across the refrigerant chamber partition wall 11. A low-temperature refrigerant supplied from outside the power conversion device 1 flows through the low-temperature chamber 61, and a high-temperature refrigerant that has received heat from the heat dissipation fins 3 flows through the high-temperature chamber 62. The low-temperature chamber 61 and the high-temperature chamber 62 are adjacent to and communicate with the radiator chamber 5 via a slit-shaped communication portion 12. As shown in FIGS. 4 and 6 , the refrigerant moves through this communication portion 12. The low-temperature chamber 61 and the high-temperature chamber 62 are arranged in parallel with the long side direction of the area where the power module 2 is mounted, and the flow of the refrigerant in the heat dissipation chamber 5 is parallel to the short side direction of the area where the power module 2 is mounted. A lid 13 is provided on the lower side of the auxiliary component chamber 8 in the third direction. The refrigerant flows into and out of the power conversion device 1 via a refrigerant inlet / outlet pipe 19.

[0016] According to this embodiment, it is possible to simultaneously achieve a reduction in the size of the power conversion device, an increase in the heat transfer coefficient, and a reduction in pressure loss. The reasons for this are described below. Figures 7 to 10 are diagrams illustrating how the heat transfer coefficient and pressure loss change depending on the direction in which the cooling water flows through the power module area. Figure 7 is a schematic diagram showing when the refrigerant flows parallel to the long side of the power module mounting area (C / D<1), Figure 8 is a schematic diagram showing when the refrigerant flows when the long side and short side of the power module mounting area are equal (C / D=1), Figure 9 is a schematic diagram showing when the refrigerant flows parallel to the short side of the power module mounting area (C / D>1), and Figure 10 is a diagram plotting C / D on the horizontal axis and pressure loss, heat transfer coefficient, and heat transfer coefficient / pressure loss on the vertical axis.

[0017] Here, pressure loss can be thought of as the loss of energy that drives the flow of a fluid. Using electricity as an analogy, the relationships are electrical resistance = fluid resistance, current = fluid flow, and voltage = pressure. Just as voltage drops when current passes through an area of ​​electrical resistance, pressure drops when fluid flow passes through an area of ​​fluid resistance. This drop in pressure is called pressure loss. In this case, energy is reduced, and this reduction in energy appears as a drop in pressure. The smaller the pressure loss, the more the refrigerant can circulate by applying only a small amount of pressure with a pump, for example, and the power consumption of the pump can be reduced.

[0018] If the height of the heat dissipation fin 3 is H, the length of the horizontal side of the rectangular power module area is C, and the length of the vertical side is D, then the perimeter can be expressed as (2C + 2D). Assuming that H and (2C + 2D) are constant, we will investigate how the pressure loss and heat transfer coefficient change when the refrigerant flows parallel to side D and the ratio C / D of C to D is changed.

[0019] If C + D = α and C / D = β, then D = α / (1 + β) C = αβ / (1 + β). If the flow rate is Q and the front face flow velocity, which is the flow velocity immediately before flowing into the heat dissipation fin 3, is U, then U = Q / (CH) = Q(1 + β) / (αβH) From the above, when C = D, that is, β = 1, then U = 2Q / (αH) Here, if the pressure loss and heat transfer coefficient when C / D = 1 are each set to 1, then it can be generally approximated that the heat transfer coefficient h is proportional to the half power of the flow velocity, and the pressure loss P is proportional to the square of the flow velocity and the first power of the flow path length, and therefore the pressure loss P and heat transfer coefficient h at an arbitrary front face flow velocity U can be organized as follows: P = [{Q(1 + β) / (αβH)} / {2Q / (αH)}] ２ ・{α / (1+β)} / {α / (1+1)} =(1+C / D) / (2(C / D) ２ ) h= [{Q(1+β) / (αβH)} / {2Q / (αH)}] １／２ = {(1+C / D) / (2C / D)} １／２

[0020] FIG. 10 plots C / D on the horizontal axis and pressure loss, heat transfer coefficient, and heat transfer coefficient / pressure loss on the vertical axis. In FIG. 10, curve L represents pressure loss, curve M represents heat transfer coefficient, and curve N represents heat transfer coefficient / pressure loss. The smaller the pressure loss, the less energy is required to circulate the refrigerant. The higher the heat transfer coefficient, the more efficiently heat generated in the power module can be dissipated to the refrigerant. Therefore, the larger the value of heat transfer coefficient / pressure loss N, the more ideal the cooling system. Here, let us denote the region where C / D<1 in the graph of FIG. 10 as 101, the region where C / D=1 as 102, and the region where C / D>1 as 103. 101 represents the case where the refrigerant flows parallel to the long sides of the power module mounting area as shown in FIG. 7, 102 represents the case where the short sides of the power module mounting area are equal to the long sides as shown in FIG. 8, and 103 represents the case where the refrigerant flows parallel to the short sides of the power module mounting area as shown in FIG. 9.

[0021] 10, it is clear that the heat transfer coefficient / pressure loss N is large in region 103, and it can be seen that a high heat transfer coefficient and low pressure loss can be obtained by flowing the refrigerant parallel to the short sides of the power module mounting area. As described above, in embodiment 1, the flow of the refrigerant in heat dissipation chamber 5 is parallel to the short sides of the area where the power module is mounted, so that the heat of the power module 2 can be efficiently transferred from the heat dissipation fins 3 to the refrigerant and pressure loss can be reduced.

[0022] On the other hand, when the refrigerant flows parallel to the short side of the area where the power module is mounted, to eliminate unevenness in heat dissipation performance, the refrigerant must be evenly distributed to all areas of the radiator fins along the long side of the power module just before it flows into the radiator fins. The unevenness in refrigerant distribution to the radiator fins increases the longer the distance in the direction perpendicular to the direction in which the refrigerant flows into the radiator fins, making it difficult to distribute the refrigerant evenly to the radiator fins. In other words, it is more difficult to distribute the refrigerant evenly to the radiator fins when the refrigerant in the heat dissipation chamber flows parallel to the short side than when it flows parallel to the long side of the area where the power module is mounted.

[0023] Considering the nature of fluid flowing through a flow path with fluid resistance, it is easier to equalize the flow just before the high fluid resistance area if there is a high fluid resistance area downstream of a low fluid resistance area. Therefore, by making the fluid resistance inside the refrigerant chamber before flowing into the heat dissipation fins sufficiently smaller than the fluid resistance inside the heat dissipation chamber, the refrigerant flowing into the heat dissipation fins can be distributed evenly. Since the larger the cross-sectional area of ​​the flow path, the smaller the fluid resistance, the larger the cross-sectional area of ​​the refrigerant chamber can be, so the refrigerant flowing into the heat dissipation fins can be distributed evenly.

[0024] According to this embodiment, by providing the refrigerant chamber 6 directly below the heat radiation chamber 5 (below in the third direction), a flow path cross-sectional area equal to the length of the heat radiation chamber 5 in the flow direction multiplied by the height of the refrigerant chamber 6 can be ensured. Therefore, compared to a configuration in which the refrigerant chamber 6 is provided to the side of the heat radiation chamber 5 (in the first direction), less space is required and the refrigerant can be distributed evenly to the heat radiation fins 3. Furthermore, by setting the fluid resistance of the communication portion 12 to be intermediate between the fluid resistances of the heat radiation chamber 5 and the refrigerant chamber 6, even refrigerant distribution can be achieved within the refrigerant chamber 6, further promoting uniform flow of the refrigerant flowing into the heat radiation fins 3.

[0025] Here, even if the communication portion 12 is a narrow slit, say, about 1.5 mm wide, with a depth of 200 mm, its cross-sectional area will be roughly the same as that of a 10 mm diameter pipe. Furthermore, the distance the refrigerant passes through the communication portion 12 is only a few millimeters, resulting in negligible fluid resistance. Meanwhile, the heat dissipation fins 3 are densely arranged, and the refrigerant constantly collides with the heat dissipation fins 3 as it flows, so it accounts for the majority of the fluid resistance in the entire cooling section. Therefore, the fluid resistance of the communication portion 12 can be set to be intermediate between the fluid resistances of the heat dissipation chamber 5 and the refrigerant chamber 6. In other words, the refrigerant chamber 6 has the highest fluid resistance, followed by the fluid resistance of the communication portion 12, and the fluid resistance of the heat dissipation chamber 5 is the lowest.

[0026] In a fluid flow field, if there is an area where the fluid resistance is high, the flow tends to be uniform upstream of the fluid resistance. The advantage of achieving uniform refrigerant distribution within the refrigerant chamber 6 is that if the flow is uniformed using the fluid resistance of the cooling fins alone, there is a possibility of uneven flow occurring upstream of the cooling fins. Therefore, by uniforming the flow in the upstream header in advance, it is possible to achieve even uniform flow throughout the entire cooling fin. Furthermore, in the second embodiment described later, when the auxiliary component 7 is thermally connected to the refrigerant chamber 6, the auxiliary component 7 is cooled uniformly due to the uniform distribution of refrigerant within the refrigerant chamber 6.

[0027] As shown in FIG. 3 , the refrigerant chamber 6 can be formed by separating the auxiliary component 7 from the heat dissipation chamber partition wall 10 by using a recess 9 on the upper side of the auxiliary component 7 in the third direction and sealing the connection with, for example, an O-ring, liquid packing, or friction stir welding (FSW). Furthermore, as shown in FIG. 5 , the auxiliary component 7 may be integrally formed with the heat dissipation chamber 5 by a method such as brazing or FSW. While the auxiliary component 7 is inserted into the auxiliary component chamber 8 from the lower side in the third direction in FIGS. 1 to 6 , it may also be inserted from the side (first direction). The communication portion 12 may be configured as a slit as shown in FIGS. 4 and 6 . Furthermore, as shown in FIG. 11 , the base 4 and a lower plate 15 may be bonded together, and gaps formed at both ends of the lower plate 15, which also serves as the refrigerant chamber and heat dissipation chamber partition plate, may be used as the communication portion 12. Furthermore, although not shown, spaced circular or elongated holes may be provided in the heat dissipation chamber partition wall 10. Alternatively, it may be a notch provided in the heat radiation chamber partition wall 10.

[0028] The heat dissipation fins 3 are made of a material with excellent thermal conductivity, such as aluminum or copper. Pin-type fins, such as those shown in FIG. 12, can be used. Furthermore, laminated fins, such as those shown in FIGS. 11 and 13, can be used, in which perforated metal sheets are stacked so that the holes communicate with each other to form a flow path. Comb-shaped straight fins, such as those shown in FIGS. 14 and 15, can also be used. FIG. 15 is a view from the T direction in FIG. 14. The gap between the auxiliary component 7 and the auxiliary component chamber 8 may be filled with a potting material, for example, to enhance earthquake resistance. The power conversion device of this embodiment may be installed either vertically or horizontally.

[0029] According to this embodiment, the refrigerant chamber 6 for supplying the refrigerant to the heat dissipation chamber 5 also serves to cool auxiliary components 7, such as a capacitor. The refrigerant chamber 6 is formed by surrounding a recess 9 on the upper surface of the auxiliary components chamber 8 with the lower wall of the heat dissipation chamber 5, or a portion of the heat dissipation chamber 5 doubles as the refrigerant chamber 6. Therefore, unlike the prior art, the refrigerant flow path is not embedded in the capacitor case, simplifying the cooling mechanism for auxiliary components, such as the capacitor, and facilitating manufacturing. Furthermore, the flow direction of the refrigerant within the heat dissipation chamber 5 is parallel to the short side of the mounting area of ​​the power module 2, thereby reducing pressure loss and increasing the heat transfer coefficient. Furthermore, the refrigerant chamber 6 for supplying the refrigerant to the heat dissipation chamber 5 is located in a space on a different level from the heat dissipation chamber 5, thereby preventing the overall device from becoming larger in size in the planar direction. Therefore, according to this embodiment, a power conversion device can be configured that is simple in structure, capable of cooling auxiliary components, is compact, and has high cooling performance for the power module.

[0030] 16 and 17 are cross-sectional views of a power conversion device according to a second embodiment, viewed from the center toward the pipe. In this embodiment, the auxiliary component 7 stored in the first embodiment is thermally connected to the refrigerant chamber 6. The auxiliary component 7 is a component that assists the power module 2 to achieve the power conversion function, and generates Joule heat when a current flows through it. Therefore, by actively releasing the heat from the auxiliary component 7 to the outside, the performance of the auxiliary component 7 can be enhanced, and the life of the auxiliary component 7 can be extended.

[0031] In this embodiment, a heat transfer member 21 is provided on the upper surface (one side in the third direction) of the auxiliary component 7, thereby thermally connecting the auxiliary component 7 and the refrigerant chamber 6. This allows heat from the auxiliary component 7 to be dissipated to the refrigerant flowing through the refrigerant chamber 6. The heat transfer member 21 may be, for example, a heat dissipation sheet, thermal grease, oil compound, phase change sheet, potting material, liquid metal, or the like.

[0032] Embodiment 3. Figure 18 is an exploded perspective view showing a power converter according to embodiment 3. In this embodiment, a capacitor 31 is used as the auxiliary component shown in embodiment 1 and is stored in the auxiliary component compartment 8. In the power converter 1, the capacitor 31 is large among the components that assist the function of the power module 2 and perform power conversion. Therefore, storing the capacitor 31 in the auxiliary component compartment 8 allows for effective use of the space in the power converter. Furthermore, since the capacitor 31 generates heat, the space between the capacitor 31 and the auxiliary component compartment 8 may be filled with a potting material or the like. Furthermore, a heat transfer member 21 may be sandwiched between the surface of the capacitor 31 adjacent to the refrigerant chamber 6 to actively dissipate heat into the refrigerant in the refrigerant chamber 6. This reduces the temperature of the capacitor 31 and extends its lifespan.

[0033] Fourth Embodiment. Figure 19 is a cross-sectional view of a portion of a power converter according to a fourth embodiment cut along a refrigerant inlet / outlet pipe, and Figure 20 is a cross-sectional view of the power converter according to the fourth embodiment, looking from the center toward the pipe. A refrigerant inlet / outlet pipe 19 is connected to the refrigerant chamber 6 for exchanging refrigerant with the outside of the power converter. If the height of the refrigerant chamber 6 in the third direction were sized to match the inner diameter u of the refrigerant inlet / outlet pipe, as in Figures 3 and 5 shown in the first embodiment, the flow path cross-sectional area would be greater than the necessary and sufficient flow path cross-sectional area to reduce the fluid resistance of the refrigerant chamber 6, leading to an increase in the size of the refrigerant chamber 6. Therefore, in this embodiment, a portion of the refrigerant chamber 6 is dug deeper, and the refrigerant inlet / outlet pipe 19 is connected thereto, thereby making the height v of the refrigerant chamber 6 smaller than the inner diameter u of the refrigerant inlet / outlet pipe 19. This configuration allows for space savings when the height of the refrigerant chamber 6 required to ensure the necessary and sufficient flow path cross-sectional area to reduce the fluid resistance of the refrigerant chamber 6 is equal to or less than the inner diameter of the refrigerant inlet / outlet pipe 19.

[0034] Fifth Embodiment. Figures 21 and 23 are perspective views showing a power converter according to a fifth embodiment, and Figures 22 and 24 are plan cross-sectional views of the power converter according to the fifth embodiment, cut at the refrigerant chamber. In this embodiment, at least one refrigerant inlet / outlet pipe 19 is connected at any position to each of the low-temperature chamber 61 and the high-temperature chamber 62 of the refrigerant chamber 6. As long as the low-temperature chamber 61 and the high-temperature chamber 62 are each connected to at least one refrigerant inlet / outlet pipe 19, the refrigerant can fill the refrigerant chamber 6 regardless of the connection position and be supplied to the heat dissipation chamber 5. In this embodiment, even if there are restrictions on the pipe layout of the vehicle or equipment in which the power converter is installed, the pipe connection positions can be determined flexibly. The number of refrigerant inlet / outlet pipes does not necessarily have to be one each for the low-temperature chamber 61 and the high-temperature chamber 62; multiple refrigerant inlet / outlet pipes may be provided depending on the refrigerant supply path, the vehicle in which the power converter is installed, or the configuration of the equipment.

[0035] 25 and 26 are plan cross-sectional views taken at the position of the refrigerant chamber in a power conversion device according to embodiment 6. In this embodiment, a bent or folded portion is provided in the refrigerant chamber partition wall 11. By providing a bent or folded portion in the refrigerant chamber partition wall 11, it is possible to change the shapes of the low-temperature chamber 61 and the high-temperature chamber 62. As a result, for example, if there is a component that is sensitive to high temperatures among the auxiliary components 7 stored in the auxiliary component chamber 8 adjacent to the refrigerant chamber 6, the low-temperature chamber 61 can be positioned near the component to suppress the temperature rise of the component.

[0036] Seventh Embodiment. Figure 27 is a perspective view showing a power converter according to a seventh embodiment, and Figure 28 is a plan cross-sectional view of the power converter according to the seventh embodiment, cut at the position of the refrigerant chamber. According to this embodiment, the centers of the refrigerant inlet / outlet pipes 19 are arranged so as to be aligned in a straight line with the long sides of the mounting area for the power modules 2. The refrigerant chamber partition wall 11 can be arranged, for example, diagonally within the refrigerant chamber 6. As shown in Figures 22 and 24, when the refrigerant chamber partition wall 11 is arranged to divide the refrigerant chamber 6 in half, arranging the refrigerant inlet / outlet pipes 19 parallel to and aligned with the long sides of the mounting area for the power modules 2 would interfere with the refrigerant chamber partition wall 11, making it impossible to do so. However, due to the piping layout of the vehicle or equipment in which the power converter is installed, there are cases in which the refrigerant inlet / outlet pipes 19 can only be aligned parallel to and aligned with the long sides of the mounting area for the power modules 2. This embodiment can be used to address such cases.

[0037] 29 is a cross-sectional view of a power converter according to embodiment 8, viewed from the center toward the pipes. In this embodiment, an L-shaped refrigerant chamber 81 is provided so as to extend laterally (to the first direction side) of the auxiliary component chamber 8. In this embodiment, the refrigerant chamber 81 is disposed so as to surround the auxiliary component chamber 8 in a U-shape, so that heat from the auxiliary component 7 can be efficiently dissipated to the refrigerant in the refrigerant chamber 81.

[0038] Embodiment 9. Figure 30 is a side view showing the heat dissipation fin portion of a power conversion device according to embodiment 9. Also, Figure 31A is a cross-sectional view showing the portion cut at the position indicated by line E-E in Figure 30, Figure 31B is a cross-sectional view showing the portion cut at the position indicated by line F-F in Figure 30, Figure 31C is a cross-sectional view showing the portion cut at the position indicated by line G-G in Figure 30, Figure 31D is a cross-sectional view showing the portion cut at the position indicated by line H-H in Figure 30, and Figure 31E is a cross-sectional view showing the portion cut at the position indicated by line I-I in Figure 30. Furthermore, Figure 32 is a view showing only the refrigerant portion of the flow path inside the heat dissipation fin.

[0039] In this embodiment, the heat dissipation fin 3 is formed by stacking metal sheets each having a plurality of holes, and the adjacent surfaces of these stacked metal sheets are joined by brazing. The holes in each metal sheet communicate with the holes in the adjacent metal sheet, and the flow paths formed by the communication between the holes are configured to be interwoven, thereby forming an intertwined spiral flow as shown in Figure 32, thereby forming a spiral flow path 91.

[0040] According to this embodiment, the refrigerant flows in a spiral pattern through the heat dissipation fins 3, which agitates the refrigerant. Furthermore, centrifugal force is constantly applied to the refrigerant, increasing the flow velocity near the inner wall 911 of the spiral flow path, thinning the thermal boundary layer and improving the heat transfer coefficient. A feature of the heat dissipation fins according to this embodiment is that the refrigerant is agitated three-dimensionally, so that heat received from the power module 2 on the surface side of the base 4 can be efficiently transferred to the heat dissipation chamber partition wall 10. Due to this feature, in this structure in which the refrigerant chamber 6 is adjacent to the heat dissipation chamber 5, heat from the power module 2 can be transferred to the refrigerant chamber 6, and the heat transferred to the refrigerant chamber 6 is dissipated to the surrounding environment or the refrigerant, thereby more efficiently cooling the power module 2.

[0041] Tenth Embodiment. Figures 33 and 34 are cross-sectional views showing the heat dissipation fin portion of a power converter according to a tenth embodiment, with Figure 34 corresponding to the structure shown in Figure 13. In this embodiment, a wall surface 101 is formed integrally with the heat dissipation fin 3 on the surface of the heat dissipation fin 3 facing the refrigerant chamber, and the wall surface 101 functions as a heat dissipation chamber partition wall between the refrigerant chamber 6 and the fin 3. This configuration makes it possible to prevent the heat dissipation chamber partition plate from being forgotten to be installed, compared to assembling it as a separate component. Furthermore, it is possible to prevent problems such as the communication portion 12 interfering with the heat dissipation fin 3 and being partially blocked due to variations in assembly. The wall surface 101 can be joined to the heat dissipation fin 3 by, for example, brazing, welding, adhesive, FSW, or the like.

[0042] Embodiment 11 Figure 35 is a cross-sectional view of the pipe side from the center of a power conversion device according to embodiment 11. In this embodiment, a dedicated cooling flow path 111 is provided adjacent to auxiliary component chamber 8 to cool auxiliary component 7. In this embodiment, because a dedicated cooling flow path 111 is provided for cooling auxiliary component 7, auxiliary component 7 can be effectively cooled even when the amount of heat generated by auxiliary component 7 is particularly large and cannot be sufficiently cooled by the configurations of embodiment 2 or embodiment 8.

[0043] The refrigerant circulating through the dedicated cooling flow path 111 may be introduced from a cooling system separate from the refrigerant circulating through the refrigerant chamber 6, for example. Furthermore, the refrigerant may be introduced from the same cooling system as the refrigerant circulating through the refrigerant chamber 6, and combined with embodiment 2 or 8. In Figure 35, the dedicated cooling flow path 111 is provided on the bottom surface (bottom side in the third direction) of the auxiliary component chamber 8, but it may also be provided on the side surface (first direction). Furthermore, it may also be provided so as to surround the auxiliary component chamber 8.

[0044] Embodiment 12. Figure 36 is an exploded perspective view showing a power converter according to embodiment 12, Figure 37 is a cross-sectional view of the power converter according to embodiment 12 looking at the pipe side from the center, and Figure 38 is a cross-sectional view showing a portion cut along the refrigerant inlet / outlet pipe of the power converter according to embodiment 12. In this embodiment, the supplied refrigerant passes through auxiliary component chamber 8, flows into low-temperature chamber 61, and is discharged from high-temperature chamber 62. When the refrigerant is supplied from the inlet side of refrigerant inlet / outlet pipe 19, it flows into refrigerant flow path 121 of auxiliary component chamber 8 arranged inside auxiliary component chamber 8, absorbs heat from auxiliary components 7 via the side wall of refrigerant flow path 121 of auxiliary component chamber 8, and flows into low-temperature chamber 61.

[0045] This structure allows the auxiliary component 7 to be cooled efficiently without providing a separate flow path dedicated to cooling the auxiliary component 7 as shown in embodiment 11. Furthermore, because the auxiliary component 7 is cooled using the refrigerant at the most upstream position, the temperature of the refrigerant flowing into the auxiliary component 7 is the lowest. Therefore, this is an effective cooling structure when the allowable temperature of the auxiliary component 7 is particularly low.

[0046] Embodiment 13. Figure 39 is an exploded perspective view showing a power converter according to embodiment 13, Figure 40 is a cross-sectional view of the power converter according to embodiment 12 looking at the pipe side from the center, and Figure 41 is a cross-sectional view showing a portion cut along the refrigerant inlet / outlet pipes of the power converter according to embodiment 13. In this embodiment, the supplied refrigerant flows into low-temperature chamber 61, flows from high-temperature chamber 62 into refrigerant flow path 131, passes through auxiliary part 7, and is discharged from the discharge pipe.

[0047] This structure makes it possible to efficiently cool the auxiliary component 7 without providing a separate flow path dedicated to cooling the auxiliary component 7 as shown in embodiment 11. Furthermore, since the auxiliary component 7 is cooled using the refrigerant flowing out of the high-temperature chamber 62, the temperature of the refrigerant flowing into the auxiliary component 7 is higher than in embodiment 12, and therefore the effect of cooling the auxiliary component 7 is reduced compared to embodiment 12. However, this can be an effective cooling means for the auxiliary component 7 when the allowable temperature of the auxiliary component 7 is high, or when there are layout restrictions on the piping of the vehicle or equipment equipped with a power conversion device.

[0048] Embodiment 14. Figure 42 is an exploded perspective view showing a power converter according to embodiment 14, and Figure 43 is a cross-sectional view of the power converter according to embodiment 14, looking from the center toward the pipes. In this embodiment, a refrigerant supplied from the outside passes through auxiliary component chamber 8, then flows into low-temperature chamber 61, then passes through high-temperature chamber 62, flows into refrigerant flow path 141, passes through auxiliary component chamber 8 again, and is discharged. This structure is a combination of the structure of embodiment 12 and the structure of embodiment 13, and provides an even greater effect in cooling auxiliary component 7 than embodiments 12 and 13.

[0049] Fifteenth Embodiment. Figure 44 is a cross-sectional view of a power converter according to a fifteenth embodiment, viewed from the center toward the pipe side. In this embodiment, a bus bar 151 is provided to electrically connect the auxiliary component 7 and the power module 2. The bus bar 151 is located on the low-temperature chamber 61 side of the heat dissipation chamber 5 and is thermally connected. The bus bar 151 is made of a material with low electrical resistance, such as copper. However, reducing the amount used to reduce costs increases electrical resistance and Joule heat. Therefore, heat generated by the bus bar 151 is dissipated to the low-temperature refrigerant flowing through the low-temperature chamber 61 via a heat transfer member 152. This allows the bus bar 151 to be cooled efficiently and reduces the amount of material used for the bus bar 151. Examples of the heat transfer member 152 that can be used include a heat dissipation sheet, thermal grease, oil compound, phase change sheet, potting material, and liquid metal.

[0050] Sixteenth Embodiment Figure 45 is a cross-sectional view of a power converter according to a sixteenth embodiment, viewed from the center toward the pipes. In this embodiment, a heat-generating component 161 is disposed between the auxiliary component chamber 8 and the refrigerant chamber 6, and the heat-generating component 161 is thermally connected to the refrigerant chamber 6. The heat-generating component 161 is, for example, a bus bar electrically connecting the auxiliary component 7 and the power module 2, as shown in the fifteenth embodiment, and serves as an effective means for dissipating heat when another heat-generating component 161 is located above the auxiliary component 7 (above in the third direction). Furthermore, as shown in the second embodiment, when the auxiliary component 7 cannot be directly cooled by the refrigerant chamber 6, the auxiliary component 7 can also be indirectly cooled via the heat-generating component 161 located above it.

[0051] Embodiment 17. Figure 46 is a cross-sectional view of a power converter according to embodiment 17, viewed from the center toward the pipe. According to this embodiment, a current sensor core, or a current sensor core and a current sensor 171, is built into the auxiliary component chamber 8. In the above structure, the current sensor core, or the current sensor core and the current sensor 171, is fixed to the auxiliary component chamber 8 by, for example, potting. By building the current sensor core, or the current sensor core and the current sensor 171 into the auxiliary component chamber 8, there is no need to fix them using a separate mold or fixing means such as bolts, and the structure can be simplified.

[0052] Embodiment 18. Figure 47 is a perspective view showing the integrally molded auxiliary component chamber and refrigerant chamber recess of a power converter according to embodiment 18. Figure 48 is a side view of the integrally molded auxiliary component chamber and refrigerant chamber recess of a power converter according to embodiment 18, as seen from the opening. Figure 49 is a cross-sectional view of the integrally molded auxiliary component chamber and refrigerant chamber recess of a power converter according to embodiment 18. According to this embodiment, the recess 9 forming the auxiliary component chamber 8 and the refrigerant chamber 6 is formed integrally from resin or metal, forming an integrally molded auxiliary component chamber and refrigerant chamber recess 180. As shown in Figures 48 and 49, the auxiliary component chamber 8 has a shape that does not catch when the mold is removed from the opening, making integral molding easier. In this embodiment, the recess 9 forming the auxiliary component chamber 8 and the refrigerant chamber 6 is molded integrally, which improves productivity and simplifies the structure compared to when they are separate parts. In Figures 47 to 49, the opening of the auxiliary parts chamber 8 is perpendicular to the vertical stacking structure of the heat dissipation chamber, refrigerant chamber, and auxiliary parts chamber, i.e., opens to the side, but this is not limited to this and an opening may be provided on the bottom surface.

[0053] Embodiment 19. Figure 50 is a perspective view showing an electric vehicle drive device equipped with a power conversion device according to embodiment 19, Figure 51 is a front view seen from direction P in Figure 50, Figure 52 is a front view seen from direction Q in Figure 50, and Figure 53 is a side view seen from direction R in Figure 50. This embodiment relates to an electric vehicle drive device in which a motor 191 and a reduction gear 192 are provided alongside the power conversion device described in embodiments 1 to 18, and these are housed in a rectangular parallelepiped section 193. Because the above power conversion device can be made compact, a compact electric vehicle drive device can be constructed by arranging and integrating it in the surplus space of the motor 191 and reduction gear 192.

[0054] The motor 191 and reduction gear 192 for driving an electric vehicle are generally cylindrical, but if the mounting space for the electric vehicle is provided as a rectangular parallelepiped, excess space is created in the rectangular parallelepiped for the motor 191 and reduction gear 192, resulting in inefficient use of the mounting space. Therefore, as shown in Figures 50 to 53, for example, by making the volume of the power conversion device 1 smaller than the volume of the rectangular parallelepiped section 193 that houses the motor 191 and reduction gear 192 minus the volume of the motor 191 and reduction gear 192, the excess space can be used efficiently.

[0055] Twenty-first embodiment. Figure 54 is a schematic diagram showing an electric vehicle drive device operating system for operating an electric vehicle drive device according to the nineteenth embodiment. The electric vehicle drive device is operated by a control device 200, which adjusts the amount of refrigerant flowing through the power conversion device 1 by detecting the temperature and other parameters of the electric vehicle drive device. Information is provided to an operator via a communication means such as a network, allowing the operator to check the current status. Figure 55 is a block diagram showing an example of the hardware configuration of the control device 200. The hardware of the control device 200 includes a processor 201 and a storage device 202. Although not shown, the storage device 202 includes a volatile storage device such as random access memory and a non-volatile auxiliary storage device such as flash memory. Alternatively, a hard disk auxiliary storage device may be used instead of flash memory. The processor 201 executes a program input from the storage device 202. In this case, the program is input to the processor 201 from the auxiliary storage device via the volatile storage device. The processor 201 may output data such as calculation results to a volatile storage device of the storage device 202, or may store the data in an auxiliary storage device via the volatile storage device. The processor 201 then reads and executes programs stored in the storage device 202 to perform various functions.

[0056] Although various exemplary embodiments and examples are described in this application, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are contemplated within the scope of the technology disclosed in this specification. For example, this includes cases where at least one component is modified, added, or omitted, or where at least one component is extracted and combined with components of another embodiment.

[0057] REFRIGERATED PARTS LIST 1 Power conversion device, 2 Power module, 3 Heat dissipation fin, 4 Base, 5 Heat dissipation chamber, 6 Refrigerant chamber, 7 Auxiliary parts, 8 Auxiliary parts chamber, 9 Recess, 10 Heat dissipation chamber partition wall, 11 Refrigerant chamber partition wall, 12 Communication part, 13 Lid, 19 Refrigerant inlet / outlet pipe, 21 Heat transfer member, 31 Condenser, 61 Low temperature chamber, 62 High temperature chamber, 91 Spiral flow path, 101 Wall surface, 111 Dedicated cooling flow path, 151 Bus bar, 161 Heat-generating parts, 171 Current sensor core or current sensor core and current sensor, 191 Motor, 192 Reduction gear, 193 Rectangular parallelepiped part.

Claims

1. A power conversion device comprising a power module for converting electric power, a heat dissipation chamber for storing heat dissipation fins that dissipate heat generated by the power module to a refrigerant, a refrigerant chamber for distributing and collecting the refrigerant to the heat dissipation fins, and an auxiliary component chamber for storing auxiliary components for assisting power conversion, wherein the power module, the heat dissipation chamber, the refrigerant chamber, and the auxiliary component chamber are arranged in order from one side to the other side in a third direction, the refrigerant chamber is composed of a recess on one side in the third direction of the auxiliary component chamber, and is divided into a low-temperature chamber and a high-temperature chamber according to the temperature of the refrigerant flowing through while being separated by a refrigerant chamber partition wall, the low-temperature chamber and the high-temperature chamber communicate with the heat dissipation chamber through a communication portion, the low-temperature chamber and the high-temperature chamber are arranged parallel to the long side direction of the region where the power module is mounted, and the flow of the refrigerant in the heat dissipation chamber is parallel to the short side direction of the region where the power module is mounted.

2. The power conversion device according to claim 1, wherein the refrigerant chamber is formed by a space surrounded by the recess and a heat dissipation chamber partition wall in contact with the bottom surface of the heat dissipation chamber.

3. The power conversion device according to claim 1, wherein the refrigerant chamber is formed by a space integrated with the heat dissipation chamber.

4. The power conversion device according to any one of claims 1 to 3, wherein the fluid resistance is large in the order of the refrigerant chamber, the communication portion, and the heat dissipation chamber.

5. The power conversion device according to any one of claims 1 to 4, wherein a heat transfer member is provided between the auxiliary component and the refrigerant chamber.

6. The power conversion device according to any one of claims 1 to 5, wherein a capacitor is used as the auxiliary component.

7. The power conversion device according to any one of claims 1 to 6, wherein a refrigerant inlet / outlet pipe is connected to the refrigerant chamber, and the height of the refrigerant chamber is smaller than the inner diameter of the refrigerant inlet / outlet pipe.

8. The power conversion device according to any one of claims 1 to 7, wherein a refrigerant inlet / outlet pipe is connected to the refrigerant chamber, and at least one refrigerant inlet / outlet pipe is connected to the low-temperature chamber and the high-temperature chamber.

9. The power conversion device according to any one of claims 1 to 8, wherein a bent portion or a folded portion is provided on the refrigerant chamber partition wall for partitioning the low-temperature chamber and the high-temperature chamber.

10. The power conversion device according to any one of claims 1 to 6, wherein a refrigerant inlet / outlet pipe is connected to the refrigerant chamber, and the refrigerant inlet / outlet pipe is arranged so as to be located on the same straight line with respect to the long side direction of the region where the power module is mounted.

11. The power conversion device according to any one of claims 1 to 10, wherein the refrigerant chamber is formed in an L shape, and the refrigerant chamber is located on the first direction side portion which is the short side direction of the auxiliary component chamber.

12. The power conversion device according to any one of claims 1 to 11, wherein the heat dissipation fins are formed by laminating sheet metals having a plurality of holes, and spiral flow paths for the refrigerant are formed by the holes provided in the sheet metals communicating with the holes of the adjacent sheet metals.

13. The power conversion device according to claim 2, wherein a wall surface is integrally formed with the heat dissipation fins on the surface of the heat dissipation fins facing the refrigerant chamber, and the wall surface functions as a heat dissipation chamber partition wall between the refrigerant chamber.

14. The power conversion device according to any one of claims 1 to 13, wherein a dedicated cooling flow path is provided at a position adjacent to the auxiliary component chamber.

15. The power conversion device according to any one of claims 1 to 13, wherein the supplied refrigerant flows into the low temperature chamber after passing through the auxiliary component chamber, and is discharged from the high temperature chamber.

16. The power conversion device according to any one of claims 1 to 13, wherein the supplied refrigerant flows into the low temperature chamber, passes through the high temperature chamber, and then passes through the auxiliary component chamber and is discharged.

17. The power conversion device according to any one of claims 1 to 13, wherein the supplied refrigerant passes through the auxiliary component chamber, then flows into the low temperature chamber, and then passes through the high temperature chamber and passes through the auxiliary component chamber again and is discharged.

18. The power conversion device according to any one of claims 1 to 17, wherein a bus bar for electrically connecting the auxiliary component and the power module is located on the low temperature chamber side of the heat dissipation chamber.

19. The power conversion device according to any one of claims 1 to 18, wherein a heat generating component is arranged between the auxiliary component chamber and the refrigerant chamber, and the heat generating component is thermally connected to the refrigerant chamber.

20. The power conversion device according to any one of claims 1 to 19, wherein a current sensor core, or a current sensor core and a current sensor are built in the auxiliary component chamber.

21. The power conversion device according to any one of claims 1 to 20, wherein the auxiliary component chamber and the recess forming the refrigerant chamber are integrally formed.

22. An electric vehicle drive device in which a motor and a reduction gear are provided together with the power conversion device according to any one of claims 1 to 21.

23. The electric vehicle drive device according to claim 22, wherein the volume of the power conversion device is smaller than the volume obtained by subtracting the volumes of the motor and the reduction gear from the volume of the rectangular parallelepiped portion that houses the motor and the reduction gear.

24. An electric vehicle drive device operation system for operating the electric vehicle drive device according to claim 22 or claim 23, the electric vehicle drive device operation system adjusting the amount of the refrigerant flowing through the power conversion device by detecting the temperature of the electric vehicle drive device.

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