Power Conversion Device

Abstract

To provide a power conversion device having a compact size. [Solution] A power conversion device (100) includes a reactor (13), a smoothing capacitor (42) electrically connected to the reactor (13), a housing (150) that houses the reactor (13) and the smoothing capacitor (42), and a refrigerant flow path (154) through which a refrigerant flows to cool the reactor (13). The housing (150) has a reactor housing section (152) in which the reactor (13) is disposed. The smoothing capacitor (42) is disposed outside the area facing an opening (152a) in the reactor housing section (152).

Description

[Technical Field]

[0001] The present disclosure relates to a power conversion device. [Background technology]

[0002] As disclosed in Patent Document 1, there is a power conversion device that includes a reactor and a smoothing capacitor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-14834 Summary of the Invention [Problem to be solved by the invention]

[0004] It is possible to reduce the size of the reactor in a power conversion device. However, a configuration in which the reactor is reduced in size increases the heat generation density of the reactor. Therefore, there is a risk that the size of the power conversion device will increase if the distance between the reactor and the smoothing capacitor is increased or a heat transfer suppressing member is disposed between the reactor and the smoothing capacitor.

[0005] One disclosed object is to provide a power conversion device with a reduced size. [Means for solving the problem]

[0006] The power conversion device disclosed herein comprises: A reactor (13), a smoothing capacitor (42) electrically connected to the reactor; a housing (150) that houses a reactor and a smoothing capacitor; a refrigerant flow path (154) through which a refrigerant for cooling the reactor flows; The housing has a hole (152) in which the reactor is disposed, The smoothing capacitor is arranged outside the region of the hole facing the opening (152a).

[0007] The power conversion device disclosed herein can suppress the heat transfer from the reactor to the smoothing capacitor through the opening. Therefore, the power conversion device does not need to increase the distance between the reactor and the smoothing capacitor or to place a heat transfer suppressing member between the reactor and the smoothing capacitor in order to reduce the thermal impact on the smoothing capacitor. This allows the power conversion device to be made smaller in size.

[0008] The various aspects disclosed in this specification employ different technical means to achieve their respective objectives. The reference numerals in parentheses in the claims and in this section indicate examples of correspondences with the embodiments described below, and are not intended to limit the technical scope. The objectives, features, and advantages disclosed in this specification will become clearer by referring to the following detailed description and the accompanying drawings. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a circuit diagram showing a schematic configuration of a power conversion device. [Figure 2] FIG. 1 is a plan view showing a schematic configuration of a power conversion device. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. [Figure 4] FIG. 2 is a perspective view showing a schematic configuration of a reactor. [Figure 5] FIG. 10 is a cross-sectional view showing a schematic configuration of a power conversion device according to a first modification. [Figure 6] FIG. 10 is a plan view showing a schematic configuration of a power conversion device according to a second embodiment. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII in FIG. [Figure 8] FIG. 10 is a plan view showing a schematic configuration of a power conversion device according to a second modification. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, several embodiments for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, parts corresponding to matters described in the preceding embodiment may be assigned the same reference numerals, and duplicated explanations may be omitted. In each embodiment, when only a part of the configuration is described, other parts of the configuration can be applied by referring to the other embodiment described earlier. In the following, three mutually orthogonal directions are referred to as the X direction, the Y direction, and the Z direction.

[0011] (First embodiment) A power conversion device 100 of this embodiment will be described with reference to Figs. 1 to 4. As shown in Fig. 1, the power conversion device 100 is configured to be connectable between a battery 200 and a motor 300. The battery 200 is a DC power supply. The battery 200 has a positive electrode and a negative electrode. The motor 300 is a three-phase AC motor. The motor 300 has a U-phase coil, a V-phase coil, a W-phase coil, etc.

[0012] The power conversion device 100 is configured to be mountable on, for example, a mobile object. Examples of mobile objects include vehicles such as electric cars, hybrid cars, and fuel cell cars, flying objects such as electric vertical take-off and landing aircraft and drones, ships, construction machinery, agricultural machinery, etc. However, the power conversion device 100 can also be mounted on devices other than mobile objects.

[0013] <Circuit configuration of power conversion device> The power conversion device 100 includes a boost converter circuit 10 and an inverter circuit 20. The power conversion device 100 also includes a filter capacitor 41 and a smoothing capacitor 42. The power conversion device 100 also includes, as wiring sections, low-voltage system lines 31 and 32, high-voltage system lines 33 and 34, and phase output lines 35 to 37. The power conversion device 100 is merely an example.

[0014] The low-voltage lines 31 and 32 are power wirings provided mainly in the upstream stage of the boost converter circuit 10. The low-voltage P line 31 is connected to the positive electrode of the battery 200 and the boost converter circuit 10. The low-voltage N line 32 is connected to the negative electrode of the battery 200 and the boost converter circuit 10.

[0015] The high-voltage lines 33 and 34 are power wirings provided mainly in the rear stage of the boost converter circuit 10. The high-voltage P line 33 is connected to the high-potential side of the boost converter circuit 10. The high-voltage N line 34 is connected to the low-potential side of the boost converter circuit 10.

[0016] The phase output lines 35 to 37 are output wirings provided between the inverter circuit 20 and the motor 300. The U-phase output line 35 is connected to a connection point between the U-phase upper arm element 21 and the U-phase lower arm element 22, which will be described later, and to the U-phase coil. The V-phase output line 36 is connected to a connection point between the V-phase upper arm element 23 and the V-phase lower arm element 24, which will be described later, and to the V-phase coil. The W-phase output line 37 is connected to a connection point between the W-phase upper arm element 25 and the W-phase lower arm element 26, which will be described later, and to the W-phase coil.

[0017] The boost converter circuit 10 includes an upper arm element 11, a lower arm element 12, and a reactor 13. In this embodiment, semiconductor switching elements are used as the upper arm element 11 and the lower arm element 12. In this embodiment, an IGBT is used as an example of the semiconductor switching element. IGBT is an abbreviation for Insulated Gate Bipolar Transistor. However, a MOSFET or the like can also be used as the semiconductor switching element.

[0018] The upper arm element 11 and the lower arm element 12 are connected in series between a high-voltage P line 33 and a high-voltage N line 34. The collector electrode of the upper arm element 11 is connected to the high-voltage P line 33. The emitter electrode of the lower arm element 12 is connected to the high-voltage N line 34 (low-voltage N line 32).

[0019] The emitter electrode of upper arm element 11 is connected to the collector electrode of lower arm element 12. The point where the emitter electrode of upper arm element 11 and the collector electrode of lower arm element 12 are connected corresponds to the connection point between upper arm element 11 and lower arm element 12. The connection point between upper arm element 11 and lower arm element 12 is connected to the positive electrode of battery 200 via reactor 13 and low-voltage P line 31.

[0020] The inverter circuit 20 includes a U-phase upper and lower arm circuit 20u, a V-phase upper and lower arm circuit 20v, and a W-phase upper and lower arm circuit 20w. The U-phase upper and lower arm circuit 20u includes a U-phase upper arm element 21 and a U-phase lower arm element 22. The V-phase upper and lower arm circuit 20v includes a V-phase upper arm element 23 and a V-phase lower arm element 24. The W-phase upper and lower arm circuit 20w includes a W-phase upper arm element 25 and a W-phase lower arm element 26.

[0021] Each of the phase arm elements 21 to 26 is a semiconductor switching element. In this embodiment, an IBGT is used as an example of each of the phase arm elements 21 to 26. However, each of the phase arm elements 21 to 26 may also be a MOSFET or the like. Each of the phase arm elements 21 to 26 can also be considered as a circuit component.

[0022] U-phase upper arm element 21 and U-phase lower arm element 22 are connected in series between high voltage P line 33 and high voltage N line 34. The collector electrode of U-phase upper arm element 21 is connected to high voltage P line 33. The emitter electrode of U-phase lower arm element 22 is connected to high voltage N line 34.

[0023] The emitter electrode of U-phase upper arm element 21 is connected to the collector electrode of U-phase lower arm element 22. The point at which the emitter electrode of U-phase upper arm element 21 and the collector electrode of U-phase lower arm element 22 are connected corresponds to the connection point between U-phase upper arm element 21 and U-phase lower arm element 22. The connection point between U-phase upper arm element 21 and U-phase lower arm element 22 is connected to U-phase output line 35. The same applies to V-phase upper and lower arm circuit 20v and W-phase upper and lower arm circuit 20w.

[0024] The filter capacitor 41 is connected to the low-voltage P line 31 and the low-voltage N line 32. The smoothing capacitor 42 is connected to the high-voltage P line 33 and the high-voltage N line 34. The smoothing capacitor 42 is electrically connected to the reactor 13 via the arm elements 11, 12, etc.

[0025] <Reactor> Here, reactor 13 will be described with reference to Figures 3 and 4. In Figure 3, reactor 13 is illustrated in a simplified form to avoid cluttering the drawing.

[0026] As shown in Fig. 4, reactor 13 includes coil 131 wound around a core and coil cover 134 that holds coil 131. The dashed-dotted line in Fig. 4 indicates the coil axis that is the axis around which coil 131 is wound. It can be said that coil 131 is wound around the coil axis. Coil 131 also includes a winding portion wound around the core and extension portions that extend from both ends of the winding portion.

[0027] Coil 131 includes a conductive linear member and an electrically insulating covering member 135 that covers the linear member. Both ends of the linear member are exposed from covering member 135 and serve as terminals 132 and 133. That is, coil 131 includes terminal 132, which is an end on one side, and terminal 133, which is an end on the other side. Terminals 132 and 133 are also part of an extension portion of coil 131. The linear member can also be referred to as an electric wire or a copper wire.

[0028] As shown in Fig. 4, the coil 131 is wound to have linear portions and curved portions. The linear portions are arranged adjacent to each other along the coil axis. In this embodiment, the coil axis is a straight line extending in the Y direction. The coil axis corresponds to the winding axis of the coil 131.

[0029] Coil 131 has one surface 136 and a back surface 137, which is the surface opposite one surface 136, formed by a plurality of linear portions. Coil 131 also has side surfaces that are continuous with one surface 136 and back surface 137. One surface 136 and back surface 137 are surfaces of coil 131 that have a large area. In other words, one surface 136 and back surface 137 have a larger area than the side surfaces.

[0030] It should be noted that the first surface 136 and the back surface 137 can be considered as flat surfaces. The first surface 136 and the back surface 137 may have recesses formed between adjacent linear portions.

[0031] 3, in this embodiment, as an example, reactor 13 is employed in which the extension portion of coil 131 is bent. That is, the extension portion of coil 131 extends in the X direction relative to the winding portion, and further extends in the Z direction. However, the present disclosure is not limited thereto.

[0032] <Capacitor> 2 and 3, filter capacitor 41 includes a capacitor base 141 and terminals 143 and 144. Terminals 143 and 144 protrude in the Z direction from capacitor base 141. Smoothing capacitor 42 includes a capacitor base 142 and terminals 145 and 146. Terminals 145 and 146 protrude in the Z direction from capacitor base 142.

[0033] 2 and 3, the reactor 13, the smoothing capacitor 42, and the filter capacitor 41 are arranged in this order in the X direction. However, the present disclosure is not limited thereto. The power conversion device 100 may be arranged in the X direction in the reactor 13, the filter capacitor 41, and the smoothing capacitor 42 in this order.

[0034] <Structure of power conversion device> Here, the structure of the power conversion device 100 will be described with reference to Fig. 2 and Fig. 3. For convenience, Fig. 2 to Fig. 4 show only a part of the power conversion device 100. That is, Fig. 2 and Fig. 3 mainly show the portion where the reactor 13 and the smoothing capacitor 42 are provided. Fig. 4 is a perspective view showing an example of the reactor 13.

[0035] 2 and 3, the power conversion device 100 includes circuit elements such as the above-mentioned reactor 13, arm elements 21 to 26 of each phase, a filter capacitor 41, and a smoothing capacitor 42, in addition to the arm elements 11 and 12. The power conversion device 100 also includes a power board 110, a control board 120, a housing 150, a cooling plate 160, sealing members 171 and 172, and a base member 190. The arm elements 11 and 12 and the arm elements 21 to 26 of each phase are also collectively referred to as semiconductor switching elements 11, 12, and 21 to 26.

[0036] The circuit elements, power board 110, control board 120, and housing 150 are attached to base member 190. Base member 190 is a member whose main component is a metal such as aluminum or copper. Base member 190 has side wall portions 191 and a bottom wall portion 192. Side wall portion 191 is provided with an inlet 191h that communicates with refrigerant flow path 154, which will be described later. Housing 150, which will be described later, is mounted on bottom wall portion 192.

[0037] 3, the power board 110 includes an insulating board 111 on which conductive wiring is formed, and an inter-board connector 113. The power board 110 is disposed opposite a control board 120, which will be described later, in the Z direction.

[0038] On the power board 110, the electrodes of the semiconductor switching elements 11, 12, 21 to 26 are electrically connected to wiring formed on the insulating board 111.

[0039] The inter-board connector 113 is a connector for electrically connecting to the control board 120. The inter-board connector 113 is electrically connected to the control electrodes of the semiconductor switching elements 11, 12, and 21 to 26 via wiring. The inter-board connector 113 is electrically connected to the inter-board connector 123 in a state where the power board 110 and the control board 120 are arranged opposite each other. Therefore, the control electrodes of the semiconductor switching elements 11, 12, and 21 to 26 are electrically connected to the control device 122, which will be described later, via the inter-board connector 113.

[0040] Furthermore, the power board 110 is provided with a plurality of through holes, into which terminals 132 and 133 of the reactor 13 and terminals 143 to 146 of the capacitors 41 and 42 are inserted. The reactor 13 and the capacitors 41 and 42 are electrically connected to the semiconductor switching elements 11, 12, 21 to 26 via wiring formed on the insulating board 111.

[0041] 3, the control board 120 includes an insulating board 121 on which conductive wiring is formed, a control device 122, and an inter-board connector 123. The control device 122 and the inter-board connector 123 are electrically connected to the wiring formed on the insulating board 121. The control device 122 controls the on / off of the semiconductor switching elements 11, 12, 21 to 26. The power board 110 and the control board 120 correspond to circuit boards.

[0042] 3, the housing 150 includes a housing base 151, a reactor housing portion 152, a capacitor housing portion 153, and a refrigerant flow path 154. In other words, the housing 150 is a member that houses the reactor 13 and the capacitors 41 and 42.

[0043] The housing 150 is disposed opposite the power board 110 in the Z direction. The power conversion device 100 is disposed in the Z direction with the housing 150, power board 110, and control board 120 stacked in this order. The housing base 151 (housing 150) is provided with a refrigerant flow path 154 and is in contact with the refrigerant 180. Therefore, the housing base 151 also functions as a cooler. The housing base 151 is preferably made of a material with high thermal conductivity. The housing base 151 is mainly composed of a metal such as aluminum or copper, for example.

[0044] The reactor accommodating portion 152 is a portion where the reactor 13 is disposed. The reactor accommodating portion 152 is a hole with a bottom that is provided in the X direction with respect to the housing base 151. The reactor accommodating portion 152 can also be said to be a recess provided in the housing base 151. Therefore, it can also be said that the housing base 151 is provided with the reactor accommodating portion 152 that is recessed in the X direction.

[0045] The reactor accommodating portion 152 has an opening 152a in the X direction. The opening 152a is provided, for example, to arrange the terminals 132, 133 (extension portions) outside the reactor accommodating portion 152. The opening 152a can also be said to be an open end of the reactor accommodating portion 152. The opening 152a is provided in an annular shape on the YZ plane. The extension portion of the reactor 13 is surrounded by the opening 152a. The YZ plane is an imaginary plane defined by a Y axis extending in the Y direction and a Z axis extending in the Z direction. The reactor accommodating portion 152 corresponds to a hole portion.

[0046] The reactor accommodating portion 152 has the reactor 13 disposed therein and is provided with a sealing member 171. The sealing member 171 is in contact with a part of the reactor 13 and the housing base portion 151. The reactor 13 is mainly sealed with the sealing member 171 at the coil 131. The terminals 132 and 133 are exposed from the sealing member 171. The terminals 132 and 133 are provided to pass through the opening 152a and reach the outside of the reactor accommodating portion 152.

[0047] The capacitor housing portion 153 is a portion where the capacitors 41 and 42 are arranged. The capacitor housing portion 153 is a bottomed hole provided in the Z direction with respect to the housing base portion 151. The capacitor housing portion 153 has an opening provided in the Z direction. The opening can also be said to be the open end of the capacitor housing portion 153. The opening is provided in a ring shape on the XY plane. The XY plane is an imaginary plane defined by the X axis and the Y axis extending in the X direction.

[0048] Capacitors 41 and 42 are arranged in capacitor housing section 153, and sealing member 172 is provided therein. Sealing member 172 contacts portions of capacitors 41 and 42 and housing base 151. Capacitors 41 and 42 are sealed by sealing member 172 mainly at capacitor bases 141 and 142. Terminals 143 to 146 are exposed from sealing member 172. Terminals 143 to 146 are provided so as to reach the outside of capacitor housing section 153. Capacitor housing section 153 may be a section that houses only smoothing capacitor 42.

[0049] A housing base 151 is provided between the capacitor housing portion 153 and the reactor housing portion 152. The capacitor housing portion 153 is provided on the bottom side of the reactor housing portion 152, not on the opening 152a side of the reactor housing portion 152. That is, a part of the housing base 151 is provided between the capacitor housing portion 153 and the reactor housing portion 152. Therefore, a part of the housing base 151 is disposed between the reactor 13 and the capacitors 41, 42. Therefore, the capacitors 41, 42 can be prevented from receiving the heat generated by the reactor 13. The part of the housing base 151 corresponds to the capacitor-facing metal portion.

[0050] Furthermore, the smoothing capacitor 42 is disposed outside the opposing region of the opening 152a in the reactor accommodating portion 152. The opposing region is the region opposing the opening 152a in the direction from the bottom of the reactor accommodating portion 152 toward the opening 152a. The opposing region can also be referred to as the opening-side opposing region. The opposing region is a spatial area that faces the opening 152a on the opposite side of the opening 152a from the occupied region of the reactor 13. For example, the opposing region is a spatial area formed by projecting the opening 152a on the side opposite the reactor 13. The occupied region of the reactor 13 can also be referred to as the accommodation space of the reactor 13.

[0051] On the other hand, the area facing the opening 152a in the direction from the opening 152a toward the bottom of the reactor accommodating portion 152 can also be referred to as the bottom-side facing area. The bottom-side facing area is a spatial area that faces the opening 152a on the opposite side of the bottom of the reactor accommodating portion 152 from the area occupied by the reactor 13. In other words, the smoothing capacitor 42 is disposed in a part of the bottom-side facing area.

[0052] However, the smoothing capacitor 42 does not have to be disposed in the opposing region. Therefore, the smoothing capacitor 42 may be disposed opposite the reactor 13 in the Z direction, for example. The smoothing capacitor 42 may also be disposed on the opening 152a side rather than the bottom side of the reactor accommodating portion 152. However, it is preferable to dispose the smoothing capacitor 42 on the bottom side of the reactor accommodating portion 152 rather than on the opening 152a side, because heat is less likely to be transferred from the reactor 13. Furthermore, it is preferable that the smoothing capacitor 42 be disposed opposite the refrigerant flow path 154 in the Z direction.

[0053] Coolant flow path 154 is a flow path through which coolant 180 flows, mainly for cooling reactor 13. Coolant flow path 154 is provided in housing base 151. Coolant flow path 154 is, for example, a groove provided in housing base 151. Coolant flow path 154 is formed by the groove provided in housing base 151 and a cooling plate 160 that covers the groove. Cooling plate 160 will be described later.

[0054] The refrigerant flow path 154 is arranged to face at least two surfaces 136, 137 of the reactor 13. In the present embodiment, as an example, the refrigerant flow path 154 is provided to face one surface 136 and the back surface 137. This allows the power conversion device 100 to improve the cooling performance for cooling the reactor 13. In other words, the power conversion device 100 can improve the cooling performance compared to a configuration in which the refrigerant flow path 154 is arranged to face only one surface of the reactor 13.

[0055] As described above, the housing 150 accommodates the capacitors 41 and 42 in addition to the reactor 13. Therefore, the power conversion device 100 can also cool the capacitors 41 and 42 with the refrigerant 180.

[0056] For example, a long-life coolant (LLC) can be used as the refrigerant 180. The long-life coolant contains, for example, ethylene glycol or propylene glycol.

[0057] Cooling plate 160 includes plate portion 161 and protrusions 162 protruding from plate portion 161. Cooling plate 160 is preferably made of a material with high thermal conductivity, similar to housing base 151. Cooling plate 160 is mainly made of a metal such as aluminum or copper, for example.

[0058] The cooling plate 160 is disposed opposite the reactor 13 in the Z direction. The cooling plate 160 is disposed between the reactor 13 and the power board 110. Therefore, the cooling plate 160 is disposed between the reactor 13 and the control board 120. The cooling plate 160 corresponds to a board-facing metal portion.

[0059] The cooling plate 160 has protrusions 162 provided at positions facing the semiconductor switching elements 11, 12, 21 to 26. The protrusions 162 are provided, for example, to correspond to each of the semiconductor switching elements 11, 12, 21 to 26. In other words, the cooling plate 160 has the same number of protrusions 162 as the number of semiconductor switching elements 11, 12, 21 to 26.

[0060] An electrically insulating member 20i is disposed on the protruding portion 162. The insulating member 20i brings the protruding portion 162 and the cooling plate 160 into contact with the semiconductor switching elements 11, 12, and 21 to 26. Therefore, the cooling plate 160 is electrically insulated from the semiconductor switching elements 11, 12, and 21 to 26 by the insulating member 20i.

[0061] The power conversion device 100 can mainly suppress the propagation of noise from the reactor 13 to the power board 110 and the semiconductor switching elements mounted on the power board 110. Furthermore, the power conversion device 100 can cool the semiconductor switching elements mounted on the power board 110.

[0062] The cooling plate 160 is provided with a capacitor opening 163 in an area facing the capacitors 41 and 42 in the Z direction. The capacitor opening 163 is a hole that penetrates the cooling plate 160 in the plate thickness direction.

[0063] It is sufficient that the cooling plate 160 is disposed at least between the power conversion device 100 and the control board 120. This allows the power conversion device 100 to suppress the propagation of noise from the reactor 13 to the control board 120 and the control device 122. The power conversion device 100 can also cool the control board 120 and the control device 122.

[0064] Furthermore, the board-facing metal portion may be part of the housing base 151. This allows the power conversion device 100 to suppress propagation of noise from the reactor 13 to the power board 110, the control board 120, the semiconductor switching elements 11, 12, 21 to 26 mounted thereon, and the control device 122.

[0065] In this embodiment, as an example, the refrigerant flow path 154 is provided in the housing 150. However, the refrigerant flow path 154 may be provided in a cooler separate from the housing 150.

[0066] <Effects> As described above, in the power conversion device 100, the smoothing capacitor 42 is disposed outside the region facing the opening 152a in the reactor accommodating portion 152. Therefore, the power conversion device 100 can suppress the heat of the reactor 13 from being transferred to the smoothing capacitor 42 via the opening 152a.

[0067] Therefore, in the power conversion device 100, there is no need to increase the distance between the reactor 13 and the smoothing capacitor 42 in order to reduce the thermal effect on the smoothing capacitor 42. Furthermore, in the power conversion device 100, there is no need to place a heat transfer suppression member, which is a member separate from the housing 150, between the reactor 13 and the smoothing capacitor 42. Therefore, the size of the power conversion device 100 can be reduced.

[0068] (Variation 1) 5, the power conversion device 100 may include a cooling member 13c. The cooling member 13c is disposed between the reactor 13 and the housing 150 in the reactor accommodating portion 152. It can also be said that the cooling member 13c is disposed between the reactor 13 and the housing base 151. In other words, in the power conversion device 100, the cooling member 13c, which is different from the covering member 135, is disposed between the reactor 13 and the housing 150.

[0069] The cooling member 13c is provided between the one surface 136 and the housing 150, and between the back surface 137 and the housing 150. In this embodiment, as an example, the cooling member 13c provided in contact with the one surface 136, the back surface 137, and the housing 150 is employed.

[0070] Cooling member 13c is provided to reduce the thermal resistance between reactor 13 and housing base 151. Cooling member 13c may also be provided to suppress discharge from reactor 13 to housing 150. In this case, cooling member 13c has a thickness that is sufficient to ensure discharge from reactor 13 to housing 150. Cooling member 13c can be made of a dielectric material such as ceramics or resin, for example.

[0071] The coil axis is arranged parallel to an opposing surface that faces one surface 136 of housing 150. The opposing surface is a part of the surface that constitutes reactor accommodating portion 152. The opposing surface is also arranged between refrigerant flow path 154 and reactor 13 in housing 150, and is the surface that faces reactor 13.

[0072] (Second embodiment) Next, a power converter 100 according to a second embodiment will be described with reference to Figures 6 and 7. The second embodiment differs from the first embodiment mainly in the configuration of the housing 150 and the cooling mechanism of the cooling plate 160 for the semiconductor switching elements 11, 12, 21 to 26.

[0073] In this embodiment, as an example, the power conversion device 100 is employed which includes two reactors 13. However, the power conversion device 100 may include only one reactor 13, or may include three or more reactors 13. The coil axis of this embodiment is a straight line extending in the Y direction, similar to the first embodiment.

[0074] 6, in the power conversion device 100, the reactor 13, the semiconductor switching elements 11, 12, 21 to 26, and the smoothing capacitor 42 are arranged in this order in the X direction. The reactor 13 is provided in a housing 150. The smoothing capacitor 42 is provided in a capacitor housing 150c1. The semiconductor switching elements 11, 12, 21 to 26 are provided in a cooling mechanism.

[0075] As shown in Figures 6 and 7, the cooling mechanism includes an inlet pipe 160a through which the refrigerant 180 flows, a plurality of passage pipe sections 160b provided with refrigerant flow paths 160b1, and an outlet pipe 160c through which the refrigerant 180 flows. The refrigerant 180 flows from the external introduction pipe into the inlet pipe 160a, branches into the refrigerant flow paths 160b1 of the plurality of passage pipe sections 160b, merges into the outlet pipe 160c, and then flows out of the cooler into the external discharge pipe. The cooling mechanism is similar to the cooler of JP 2023-3806 A and can be applied by referring to JP 2023-3806 A.

[0076] 7, the housing 150 includes a housing base 151 and a heat sink 153h. The housing base 151 and the heat sink 153h are mainly made of a metal such as aluminum or copper.

[0077] The housing base 151 is provided with a reactor accommodating portion 152. The reactor accommodating portion 152 has the reactor 13 disposed therein and is provided with a sealing member 171. The reactor accommodating portion 152 is a bottomed hole provided in the Z direction with respect to the housing base 151. The reactor accommodating portion 152 is provided with an opening 152a in the Z direction.

[0078] The housing 150 is provided with a refrigerant flow path 154. The refrigerant flow path 154 is provided so as to sandwich the reactor 13. The refrigerant flow path 154 is provided opposite to the surfaces corresponding to the first surface 136 and the back surface 137. Therefore, the power conversion device 100 can improve the cooling performance for cooling the reactor 13, similar to the first embodiment.

[0079] The refrigerant flow path 154 is composed of a groove provided in the housing base 151 and a heat sink 153h that closes the groove. The heat sink 153h has fins 153f on its surface facing the refrigerant flow path 154, and the opposite surface forms part of the reactor accommodating portion 152.

[0080] The refrigerant flow path 154 is connected to the inlet pipe 160a and the outlet pipe 160c. Therefore, the refrigerant 180 flows from the external introduction pipe into the inlet pipe 160a, branches off into the refrigerant flow path 154, merges into the outlet pipe 160c, and then flows out of the cooler into the external discharge pipe.

[0081] The capacitor housing 150c1 is provided with a capacitor housing portion 150c2 that houses the smoothing capacitor 42. As in the first embodiment, the smoothing capacitor 42 is arranged outside the area facing the opening 152a in the reactor housing portion 152. In this embodiment, as an example, the capacitor housing 150c1 that is provided separately from the housing 150 is used. However, the capacitor housing 150c1 may be provided integrally with the housing 150.

[0082] The second embodiment can achieve the same effects as the first embodiment. Furthermore, in the power conversion device 100, the smoothing capacitor 42 is not disposed in the area facing the reactor accommodating portion 152 in the Z direction. Therefore, the reactor accommodating portion 152 may be a through hole. This also makes it possible to achieve the same effects as the first embodiment.

[0083] (Variation 2) 8, the smoothing capacitor 42 may be disposed adjacent to the semiconductor switching elements 11, 12, 21 to 26 in the Y direction. Even in this configuration, the smoothing capacitor 42 is disposed outside the opposing region of the opening 152a in the reactor accommodating portion 152. Therefore, the second modification can achieve the same effects as the first embodiment.

[0084] Although the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to the embodiments or structures. The present disclosure also encompasses various modifications and modifications within the scope of equivalents. In addition, although various combinations and forms are shown in the present disclosure, other combinations and forms including only one element, more, or less than one element are also within the scope and spirit of the present disclosure.

[0085] (Disclosure of technical ideas) This specification discloses multiple technical ideas described in the following multiple clauses. Some clauses may be written in a multiple dependent form, with the subsequent clause referring to the preceding clause as an alternative. Furthermore, some clauses may be written in a multiple dependent form, referring to another multiple dependent clause. These multiple dependent clauses define multiple technical ideas.

[0086] (Technical thought 1) A reactor (13), a smoothing capacitor (42) electrically connected to the reactor; a housing (150) that houses the reactor and the smoothing capacitor; a refrigerant flow path (154) through which a refrigerant for cooling the reactor flows, The housing has a hole (152) in which the reactor is disposed, The smoothing capacitor is disposed outside the area facing the opening (152a) in the hole.

[0087] (Technical thought 2) The power conversion device according to Technical Concept 1, wherein the refrigerant flow path is disposed opposite at least two surfaces (136, 137) of the reactor.

[0088] (Technical Thought 3) The power conversion device according to Technical Concept 1 or 2 further includes a cooling member (13c) arranged in the hole between the reactor and the housing.

[0089] (Technical Thought 4) The power converter according to any one of Technical Ideas 1 to 3, wherein the hole is a through hole.

[0090] (Technical Thought 5) Further provided is a circuit board (110, 120) on which a circuit element is mounted, The power conversion device according to any one of Technical Concepts 1 to 4, wherein a board-facing metal part (160) is disposed between the reactor and the circuit board.

[0091] (Technical Thought 6) The power conversion device according to any one of Technical Concepts 1 to 5, wherein a capacitor facing metal part (151) is arranged between the reactor and the smoothing capacitor. [Explanation of symbols]

[0092] 10...Boost converter circuit, 11...upper arm element, 12...lower arm element, 13...reactor, 20...inverter circuit, 21...U-phase upper arm element, 22...U-phase lower arm element, 23...V-phase upper arm element, 24...V-phase lower arm element, 25...W-phase upper arm element, 26...W-phase lower arm element, smoothing capacitors 41, 42, 100...power conversion device, 150...casing, 154...refrigerant flow path, 152...reactor accommodating section, 152a...opening, 180...refrigerant

Claims

1. A reactor (13), a smoothing capacitor (42) electrically connected to the reactor; a housing (150) that houses the reactor and the smoothing capacitor; a refrigerant flow path (154) through which a refrigerant for cooling the reactor flows, The housing has a hole (152) in which the reactor is disposed, The smoothing capacitor is disposed outside the area facing the opening (152a) in the hole.

2. The power conversion device according to claim 1 , wherein the coolant flow passages are arranged to face at least two surfaces ( 136 , 137 ) of the reactor.

3. The power conversion device according to claim 1 or 2, further comprising a cooling member (13c) arranged in the hole between the reactor and the housing.

4. The power conversion device according to claim 1 or 2, wherein the hole is a through hole.

5. Further provided is a circuit board (110, 120) on which a circuit element is mounted, The power conversion device according to claim 1 or 2, wherein a board-facing metal portion (160) is disposed between the reactor and the circuit board.

6. The power conversion device according to claim 1 or 2, wherein a capacitor facing metal part (151) is arranged between the reactor and the smoothing capacitor.

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