Electric device

Abstract

This electric device is provided with a power supply bus bar, capacitors (100A, 100B), a metal housing (120), and heat dissipation members (131, 132). The power supply bus bar connects a power supply and an electric component to each other. The capacitors are connected to the power supply bus bar, and are also connected to the ground. The metal housing has a bottom to which the capacitors are fixed so as to be connected to the ground. The heat dissipation members have insulating properties and have a thermal conductivity higher than that of the air. The capacitors have elements (31, 32, 33, 41, 42, 43) and capacitor bus bars (30, 40). The capacitor bus bars have first bus bars (50, 60), second bus bars (70, 80), and fixed bus bars (55, 65). The first bus bars connect the elements and the power supply bus bar to each other. The second bus bars connect the elements and the ground to each other. The fixed bus bars are fixed to the bottom. The heat radiation members are provided between the fixed bus bars and the bottom.

Description

Electrical Equipment CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2023-184261 filed in Japan on October 26, 2023, and the contents of the original application are incorporated by reference in their entirety.

[0002] The disclosure herein relates to electrical devices.

[0003] The resin-molded capacitor of Patent Document 1 includes a case, a capacitor element housed in the case, a bus bar attached to the capacitor element, a resin member that encases the capacitor element and the bus bar, and a heat dissipation member that extends from the inside of the resin member to the outside of the resin member.

[0004] JP 2013-191805 A

[0005] According to the configuration of Patent Document 1, heat transferred to the capacitor element and bus bar can be transferred to the outside via the resin member and the heat dissipation member. However, the resin member makes it difficult to efficiently dissipate heat to the heat dissipation member. There is a risk that the temperature of the capacitor element will rise due to heat being trapped in the resin member.

[0006] An object of the present disclosure is to provide an electrical device in which temperature rise of elements is suppressed.

[0007] An electrical device according to one aspect of the present disclosure comprises: a power bus bar connected to a power source and an electrical component; a capacitor connected to the power bus bar and also connected to ground; a metal casing having a bottom to which the capacitor is fixed and connected to ground; and a heat dissipation member that is insulating and has a higher thermal conductivity than air, wherein the capacitor has capacitor bus bars including: an element; a first bus bar connecting the element and the power bus bar; a second bus bar connecting the element and ground; and a fixed bus bar extending from the first bus bar or the second bus bar toward the bottom and fixed to the bottom, and the heat dissipation member is provided between the fixed bus bar and the bottom.

[0008] With this, heat generated when the power bus bar is energized is transferred to the bottom via the fixed bus bar and the heat dissipation member, thereby suppressing heat transfer to the device, and thus suppressing temperature rise of the device.

[0009] It should be noted that the reference numbers in parentheses in the claims merely indicate the corresponding relationship with the configurations described in the embodiments described below, and do not in any way limit the technical scope.

[0010] 3 is an electric circuit diagram of the electric device; FIG. 4 is a side view of the electric device; FIG. 5 is a plan view of the electric device as viewed from the backside; FIG. 6 is a cross-sectional view taken along line IV-IV in FIG. 3; FIG. 7 is a cross-sectional view taken along line V-V in FIG. 3; FIG. 8 is a cross-sectional view taken along line VI-VI in FIG. 3; FIG. 9 is a cross-sectional view taken along line VII-VII in FIG. 3; FIG. 10 is a plan view of the electric device in a second embodiment as viewed from the backside;

[0011] 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 will be assigned the same reference numerals, and duplicated explanations may be omitted. In each embodiment, when only a part of the configuration is described, the other previously described embodiments may be applied to the other parts of the configuration.

[0012] In addition, it is not only possible to combine parts that are explicitly stated as being possible in each embodiment, but it is also possible to partially combine embodiments, embodiments and variants, and variants even if not explicitly stated, as long as there are no particular problems with the combination.

[0013] (First embodiment) <In-vehicle system> Fig. 1 is an electrical circuit diagram of an electrical device 10 mounted on an in-vehicle system 1. The electrical device 10 is sometimes referred to as a power conversion device. The in-vehicle system 1 is equipped with a high-voltage battery 2, a motor generator 4, and the electrical device 10. The vehicle on which the in-vehicle system 1 is mounted is a hybrid vehicle that can run by switching between and / or combining the driving force of the engine and the driving force of the motor generator 4. The engine and the motor generator 4 are interconnected via a gear device 5. The gear device 5 has a role of transmitting power.

[0014] The electrical device 10 has a positive high-voltage wiring 10A, a negative high-voltage wiring 10B, an inverter 11, a connecting bus bar 14, a control circuit board 15, a smoothing capacitor 20, a Y capacitor 100, and a housing 120. The positive high-voltage wiring 10A is a wiring connected to the positive electrode of the high-voltage battery 2. The negative high-voltage wiring 10B is a wiring connected to the negative electrode of the high-voltage battery 2. The positive high-voltage wiring 10A is made up of conductive members such as a positive power supply bus bar 140. The negative high-voltage wiring 10B is made up of conductive members such as a negative power supply bus bar 150. The positive power supply bus bar 140 and the negative power supply bus bar 150 may be collectively referred to as power supply bus bars 140, 150.

[0015] The inverter 11 is connected to a positive high-voltage wiring 10A and a negative high-voltage wiring 10B. The inverter 11 includes a plurality of semiconductor modules 12. Each semiconductor module 12 includes two switching elements 13 and two diodes 13A. The two switching elements 13 are connected in series between the positive high-voltage wiring 10A and the negative high-voltage wiring 10B.

[0016] The positive input terminal 11A is connected to the collector electrode of one of the two switching elements 13 that is provided on the high potential side. The negative input terminal 11B is connected to the emitter of one of the two switching elements 13 that is provided on the low potential side. The anode of diode 13A is connected to the emitter of the corresponding switching element 13. The cathode of diode 13A is connected to the collector of the corresponding switching element 13.

[0017] A motor terminal 11C connected to the motor generator 4 is connected to the emitter of the high-potential side switching element 13 and the collector of the low-potential side switching element 13. The multiple switching elements 13 convert DC power supplied from the high-voltage battery 2 into AC power capable of driving the motor generator 4. The converted power is supplied to the motor generator 4 via a connecting bus bar 14.

[0018] The control circuit board 15 controls the on / off of the multiple switching elements 13. A control circuit that controls the on / off of the multiple switching elements 13 is mounted on the control circuit board 15. Connection terminals 11D of the multiple switching elements 13 are solder-connected to the control circuit board 15. The connection terminals 11D of the multiple switching elements 13 are electrically connected to the control circuit board 15.

[0019] The smoothing capacitor 20 mainly smoothes the DC voltage supplied from the high-voltage battery 2. The smoothing capacitor 20 is connected to a positive-side high-voltage wiring 10A and a negative-side high-voltage wiring 10B. The smoothing capacitor 20 is connected in parallel to the inverter 11 and the Y capacitor 100. The high-voltage wirings 10A and 10B electrically connect the inverter 11, the smoothing capacitor 20, the Y capacitor 100, and the high-voltage battery 2.

[0020] The Y capacitor 100 mainly removes noise components leaking from the inverter 11. The Y capacitor 100 of this embodiment includes six elements 31, 32, 33, 41, 42, and 43, two Y capacitor bus bars 30 and 40, two cases 160 and 170, two fastening members 91 and 92, and two heat dissipation members 131 and 132. The number of elements is not limited to six; it is sufficient that the number of elements is at least two or more. The Y capacitor 100 includes a positive Y capacitor 100A and a negative Y capacitor 100B. The positive Y capacitor 100A and the negative Y capacitor 100B will be described later.

[0021] Of the six elements 31, 32, 33, 41, 42, and 43, three may be referred to as positive side elements 31, 32, and 33. The positive side elements 31, 32, and 33 each include a first positive side element 31, a second positive side element 32, and a third positive side element 33. The remaining three may be referred to as negative side elements 41, 42, and 43. The negative side elements 41, 42, and 43 each include a first negative side element 41, a second negative side element 42, and a third negative side element 43.

[0022] One of the two Y capacitor bus bars 30, 40 may be referred to as the positive electrode side Y capacitor bus bar 30. The remaining one may be referred to as the negative electrode side Y capacitor bus bar 40. One of the two cases 160, 170 may be referred to as the positive electrode side case 160. The remaining one may be referred to as the negative electrode side case 170. The positive electrode side Y capacitor bus bar 30 may be referred to as the positive electrode side capacitor bus bar. The negative electrode side Y capacitor bus bar 40 may be referred to as the negative electrode side capacitor bus bar.

[0023] The three positive elements 31, 32, and 33, the positive Y capacitor bus bar 30, the positive case 160, the fastening member 91, and the heat dissipation member 131 may be collectively referred to as the positive Y capacitor 100A. The three negative elements 41, 42, and 43, the negative Y capacitor bus bar 40, the negative case 170, the fastening member 92, and the heat dissipation member 132 may be collectively referred to as the negative Y capacitor 100B.

[0024] Positive electrode side elements 31, 32, and 33 are housed in a positive electrode side case 160. A positive electrode side Y capacitor bus bar 30 connects the positive electrode of the high-voltage battery 2 to a first ground 90A via the positive electrode side elements 31, 32, and 33. The positive electrode side elements 31, 32, and 33 have positive electrode side leads 31A, 32A, and 33A connected to the positive electrode of the high-voltage battery 2, and positive electrode side G leads 31B, 32B, and 33B connected to the first ground 90A. The positive electrode side leads 31A, 32A, and 33A have a positive electrode side first lead 31A, a positive electrode side second lead 32A, and a positive electrode side third lead 33A. The positive electrode side G leads 31B, 32B, and 33B have a positive electrode side first G lead 31B, a positive electrode side second G lead 32B, and a positive electrode side third G lead 33B.

[0025] The positive Y capacitor bus bar 30 has a positive first bus bar 50, a positive second bus bar 70, and a positive fixed bus bar 55. The positive first bus bar 50 electrically connects the positive electrode of the high-voltage battery 2 to the positive leads 31A, 32A, and 33A. The positive second bus bar 70 electrically connects the positive G leads 31B, 32B, and 33B to the first ground 90A. One end of the positive fixed bus bar 55 is integrally connected to the positive first bus bar 50. The other end of the positive fixed bus bar 55 is fixed to the back surface 110B of the bottom 110 (described later) via a heat dissipation member 131. The positive first bus bar 50 and the positive leads 31A, 32A, and 33A are connected via solder 34. The positive electrode side second bus bar 70 and the positive electrode side G leads 31B, 32B, 33B are connected via solder 35.

[0026] The positive-side second bus bar 70 also has a fastening portion 75 on which a fastening member 91 is provided. The fastening portion 75 is fixed to the bottom 110 via the fastening member 91, and is thereby electrically connected to the first ground 90A. The positive-side elements 31, 32, and 33 channel noise components leaking from the inverter 11 to the first ground 90A via the positive-side second bus bar 70 and the fastening member 91.

[0027] Similarly, negative electrode elements 41, 42, and 43 are housed in the negative electrode case 170. The negative electrode Y capacitor bus bar 40 connects the negative electrode of the high-voltage battery 2 to the second ground 90B via the negative electrode elements 41, 42, and 43. The negative electrode elements 41, 42, and 43 have negative electrode leads 41A, 42A, and 43A connected to the negative electrode of the high-voltage battery 2 and negative electrode G leads 41B, 42B, and 43B connected to the second ground 90B. The negative electrode leads 41A, 42A, and 43A have a first negative electrode lead 41A, a second negative electrode lead 42A, and a third negative electrode lead 43A. The negative electrode G leads 41B, 42B, and 43B have a first negative electrode G lead 41B, a second negative electrode G lead 42B, and a third negative electrode G lead 43B.

[0028] The negative Y capacitor bus bar 40 has a negative first bus bar 60, a negative second bus bar 80, and a negative fixed bus bar 65. The negative first bus bar 60 electrically connects the negative electrode of the high-voltage battery 2 to the negative leads 41A, 42A, and 43A. The negative second bus bar 80 electrically connects the negative G leads 41B, 42B, and 43B to a second ground 90B. One end of the negative fixed bus bar 65 is integrally connected to the negative first bus bar 60. The other end of the negative fixed bus bar 65 is fixed to the back surface 110B of the bottom 110 via a heat dissipation member 132. The negative first bus bar 60 and the negative leads 41A, 42A, and 43A are connected via solder 44. The negative electrode second bus bar 80 and the negative electrode G leads 41B, 42B, 43B are connected via solder 45.

[0029] The first positive lead 31A, the second positive lead 32A, the third positive lead 33A and the first negative lead 41A, the second negative lead 42A, the third negative lead 43A may be collectively referred to as one-end leads. The first positive lead 31B, the second positive lead 32B, the third positive lead 33B and the first negative lead 41B, the second negative lead 42B, the third negative lead 43B may be collectively referred to as the other-end leads.

[0030] The negative-side second bus bar 80 also has a fastening portion 85 on which a fastening member 92 is provided. The fastening portion 85 is fixed to the bottom 110 via the fastening member 92, and is thereby electrically connected to the second ground 90B. The negative-side elements 41, 42, and 43 channel noise components leaking from the inverter 11 to the second ground 90B via the negative-side second bus bar 80 and the fastening member 92.

[0031] The heat dissipation members 131, 132 are heat dissipation sheets, gap fillers, heat dissipation grease, etc. The heat dissipation members 131, 132 have a higher thermal conductivity than air. The heat dissipation members 131, 132 are insulating. As will be explained in detail later, the heat dissipation members 131, 132 are provided between the Y capacitor bus bars 30, 40 and the bottom 110. They efficiently transfer heat from the Y capacitor bus bars 30, 40 to the bottom 110.

[0032] <Mechanical Configuration of Electrical Device> Before describing the mechanical configuration of the electrical device 10, the drawings will be described. Fig. 1 is an electrical circuit diagram of the electrical device 10. Fig. 2 is a side view of the electrical device 10. Fig. 3 is a plan view of the electrical device 10 as viewed from the rear surface 110B. Fig. 4 is a cross-sectional view of the positive Y capacitor 100A. Fig. 5 is a cross-sectional view of the positive fixed bus bar 55. Fig. 6 is a cross-sectional view of the negative Y capacitor 100B. Fig. 7 is a cross-sectional view of the negative fixed bus bar 65.

[0033] Hereinafter, the thickness direction of the bottom 110 may be referred to as the Z direction, and the direction perpendicular to the Z direction may be referred to as the orthogonal direction. One direction perpendicular to the Z direction, specifically the arrangement direction of the positive Y capacitor 100A and the negative Y capacitor 100B, is referred to as the X direction. The X direction corresponds to one direction. Furthermore, the direction perpendicular to both the Z direction and the X direction is referred to as the Y direction. Unless otherwise specified, the shape viewed from the Z direction, in other words, the shape along the XY plane defined by the X and Y directions, is referred to as the planar shape. Furthermore, the planar view from the Z direction is simply referred to as the planar view.

[0034] The housing 120 forms a single container. The housing 120 is made of a metal material. The housing 120 is made, for example, of aluminum die-casting. The housing 120 is sometimes referred to as a metal housing. The housing 120 has a bottom 110 and a side wall 115 that forms an annular shape. The bottom 110 has a flat shape with a thin thickness in the Z direction. The bottom 110 has a front surface 110A and a back surface 110B that are aligned in the Z direction. The bottom 110 has a flow path 117 between the front surface 110A and the back surface 110B through which a refrigerant passes. The refrigerant flows through the flow path 117, allowing efficient cooling of the electrical components fixed to the bottom 110. The smoothing capacitor 20 and the Y capacitor 100 are fixed to the bottom 110. This allows efficient cooling of the heat from the smoothing capacitor 20 and the Y capacitor 100 to the bottom 110.

[0035] The sidewall 115 stands up in a ring shape away from the surface 110A. The sidewall 115 has a first sidewall 111 and a second sidewall 112 aligned in the X direction, and a third sidewall 113 and a fourth sidewall 114 aligned in the Y direction. The sidewalls 115 are continuous clockwise in the order of the first sidewall 111, the third sidewall 113, the second sidewall 112, and the fourth sidewall 114. A storage space 121 is formed in the housing 120 by the bottom 110 and the sidewalls 115. The inverter 11 and the smoothing capacitor 20 are housed in this storage space 121.

[0036] In addition, a portion of power supply bus bars 140 and 150 is fixed to rear surface 110B. The remainder of power supply bus bars 140 and 150 is provided on front surface 110A. Inverter 11 and smoothing capacitor 20 are electrically connected by power supply bus bars 140 and 150 on the front surface 110A side.

[0037] The ends of the power supply bus bars 140, 150 on the rear surface 110B side are connected to the ends of the power supply bus bars 140, 150 on the front surface 110A side. Another end of the power supply bus bars 140, 150 on the rear surface 110B side is provided with a power connector that connects to the high-voltage battery 2. This allows power to be supplied from the high-voltage battery 2 to the Y capacitor 100, the smoothing capacitor 20, and the inverter 11 via the power supply bus bars 140, 150.

[0038] The power bus bars 140, 150 have four conductive portions: first conductive portions 141, 151, second conductive portions 142, 152, third conductive portions 143, 153, and fourth conductive portions 144, 154. The first conductive portions 141, 151 extend in the Y direction from the third side wall 113 toward the fourth side wall 114. A power connector is connected to the end of the first conductive portions 141, 151 on the third side wall 113 side. The second conductive portions 142, 152 are connected to the end of the first conductive portions 141, 151 on the fourth side wall 114 side.

[0039] The second conductive portions 142, 152 extend in the X direction toward the first side wall 111. The third conductive portions 143, 153 are connected to the ends of the second conductive portions 142, 152 on the first side wall 111 side. The third conductive portions 143, 153 extend in the Y direction toward the fourth side wall 114. The fourth conductive portions 144, 154 are connected to the ends of the third conductive portions 143, 153 on the fourth side wall 114 side. The fourth conductive portions 144, 154 extend in the X direction toward the second side wall 112. The ends of the fourth conductive portions 144, 154 on the second side wall 112 side are connected to the ends of the positive power bus bar 140 and the negative power bus bar 150 on the surface 110A side.

[0040] The conductive portions 141 to 143 of the positive power supply bus bar 140 are located closer to the second side wall 112 than the conductive portions 151 to 153 of the negative power supply bus bar 150. The positive Y capacitor 100A is located closer to the second side wall 112 than the conductive portions 141 to 143. The negative Y capacitor 100B is located closer to the first side wall 111 than the conductive portions 151 to 153. As an example, the capacitor 1000 is fixed to the back surface 110B via fastening members 91 and 92 as well as bolts, adhesive, or the like (not shown).

[0041] <Positive Electrode Side Y Capacitor> A tip 163 of a side wall 162 of the positive electrode side case 160 is provided on the opposite side of the tip 116 of the side wall 115 of the housing 120 in the Z direction. The three positive electrode side elements 31, 32, and 33 are lined up in the X direction in the internal space of the positive electrode side case 160. As an example, the three positive electrode side elements 31, 32, and 33 are lined up from the first side wall 111 to the second side wall 112 in the order of the positive electrode side first element 31, the positive electrode side second element 32, and the positive electrode side third element 33. Positive electrode side leads 31A, 32A, and 33A and positive electrode side G leads 31B, 32B, and 33B extend in the Z direction from the element portions of the positive electrode side elements 31, 32, and 33.

[0042] The three positive electrode side elements 31, 32, 33 are arranged such that the first positive electrode side lead 31A, the second positive electrode side lead 32A, and the third positive electrode side lead 33A are adjacent to each other in the Y direction. The three positive electrode side elements 31, 32, 33 are arranged such that the first positive electrode side lead 31B, the second positive electrode side lead 32B, and the third positive electrode side lead 33B are adjacent to each other in the Y direction. The positive electrode side leads 31A, 32A, 33A are provided closer to the third side wall 113 than the positive electrode side G leads 31B, 32B, 33B.

[0043] The positive electrode Y capacitor bus bar 30 has a thickness in the Z direction that is thinner than that of the positive electrode power supply bus bar 140. In other words, the plate thickness of the positive electrode Y capacitor bus bar 30 is thinner than that of the positive electrode power supply bus bar 140. The positive electrode first bus bar 50 electrically connects the positive electrode of the high-voltage battery 2 to the positive electrode leads 31A, 32A, and 33A. The positive electrode first bus bar 50 has a comb shape with a handle extending in the Y direction. The positive electrode first bus bar 50 has a positive electrode first extension portion 51 that corresponds to the handle, and three positive electrode second extension portions 52, 53, and 54 that correspond to the teeth. One end of the positive electrode first extension portion 51 is connected to the third conductive portion 143 by welding or the like.

[0044] The positive electrode first extension 51 is provided between the positive electrode leads 31A, 32A, and 33A and the positive electrode G leads 31B, 32B, and 33B in the Y direction. The positive electrode first extension 51 extends in the X direction from the connection portion with the third conductive portion 143 toward the second side wall 112. The positive electrode first extension 51 is located farther from the rear surface 110B than the tip 163 of the positive electrode case 160 and the upper ends of the positive electrode elements 31, 32, and 33. The positive electrode elements 31, 32, and 33 are located closer to the rear surface 110B than the positive electrode first extension 51. The positive electrode first extension 51 extends from the connection portion with the third conductive portion 143 to a position overlapping the tip 163 and the upper ends of the element portions of the positive electrode elements 31, 32, and 33.

[0045] The three positive electrode side second extension portions 52, 53, 54 are integrally connected to the positive electrode side first extension portion 51 at positions overlapping the positive electrode side elements 31, 32, 33. The three positive electrode side second extension portions 52, 53, 54 are a first parallel portion 52, a second parallel portion 53, and a third parallel portion 54 that are parallel to each other in the X direction. The first parallel portion 52 is integrally connected to the positive electrode side first element 31 at a position overlapping it. The second parallel portion 53 is integrally connected to the positive electrode side second element 32 at a position overlapping it. The third parallel portion 54 is integrally connected to the positive electrode side third element 33 at a position overlapping it. The three positive electrode side second extension portions 52, 53, 54 extend in the Y direction from the positive electrode side first extension portion 51 toward the corresponding positive electrode side leads 31A, 32A, 33A.

[0046] Through holes for passing the positive electrode leads 31A, 32A, and 33A are formed at the tips of the three positive electrode side second extensions 52, 53, and 54. The corresponding positive electrode side leads 31A, 32A, and 33A are inserted into the through holes and connected by soldering. This electrically connects the positive electrode side second extensions 52, 53, and 54 to the positive electrode side elements 31, 32, and 33.

[0047] One end of the positive electrode side fixed bus bar 55 is integrally connected to the positive electrode side first extension portion 51. In this embodiment, one end of the positive electrode side first extension portion 51 is connected between the connection portion with the third conductive portion 143 and the connection portion with the first parallel portion 52. The positive electrode side first extension portion 51 has a long side in the X direction and a short side in the Y direction. The positive electrode side first extension portion 51 has ends in the X direction and the Y direction. As an example, the positive electrode side fixed bus bar 55 is integrally connected to the Y direction end of the positive electrode side first extension portion 51. Note that the fixing location of the positive electrode side fixed bus bar 55 is not limited as long as it is provided on the positive electrode side first extension portion 51.

[0048] The positive electrode side fixed bus bar 55 extends in the Z direction from the positive electrode side first extension portion 51 toward the back surface 110B. As shown in FIG. 5 , the positive electrode side first extension portion 51 and the positive electrode side fixed bus bar 55 are substantially L-shaped in cross section. The tip 56 of the positive electrode side fixed bus bar 55 is spaced from the back surface 110B. A heat dissipation member 131 is provided on the back surface 110B so as to cover the tip 56 of the positive electrode side fixed bus bar 55. The heat dissipation member 131 is provided at least between the tip 56 of the positive electrode side fixed bus bar 55 and the back surface 110B.

[0049] The positive electrode side fixed bus bar 55, the positive electrode side leads 31A, 32A, 33A, and the positive electrode side G leads 31B, 32B, 33B extend in the same direction. Note that the positive electrode side fixed bus bar 55 does not have to be substantially L-shaped in cross section. For example, the positive electrode side fixed bus bar 55 may be substantially Z-shaped in cross section.

[0050] The positive side second bus bar 70 electrically connects the positive side elements 31, 32, and 33 to the first ground 90A. The positive side second bus bar 70 also has a comb shape with a handle extending in the Y direction. The positive side second bus bar 70 has a positive side third extension portion 71 that corresponds to the handle, and three positive side fourth extension portions 72, 73, and 74 that correspond to the teeth. A fastening portion 75 to which a fastening member 91 is attached is provided at one end of the positive side third extension portion 71. The fastening portion 75 is electrically connected to the first ground 90A via the fastening member 91.

[0051] The positive electrode-side third extension 71 is provided between the positive electrode-side leads 31A, 32A, and 33A and the positive electrode-side G leads 31B, 32B, and 33B in the Y direction. The positive electrode-side third extension 71 extends in the X direction from the connection portion with the bottom 110 toward the first side wall 111. The positive electrode-side third extension 71 is also farther from the back surface 110B than the tip 163 and the upper ends of the positive electrode-side elements 31, 32, and 33. The positive electrode-side elements 31, 32, and 33 are provided closer to the back surface 110B than the positive electrode-side third extension 71. The positive electrode-side third extension 71 extends from the connection portion with the bottom 110 to a position overlapping the tip 163 and the upper ends of the positive electrode-side elements 31, 32, and 33.

[0052] The three positive side fourth extensions 72, 73, 74 are integrally connected to the extension 71 at positions overlapping the positive side elements 31, 32, 33. The three positive side fourth extensions 72, 73, 74 are a fourth parallel portion 72, a fifth parallel portion 73, and a sixth parallel portion 74 that are parallel to each other in the X direction. The fourth parallel portion 72 is integrally connected to the positive side first element 31 at a position overlapping it. The fifth parallel portion 73 is integrally connected to the positive side second element 32 at a position overlapping it. The sixth parallel portion 74 is integrally connected to the positive side third element 33 at a position overlapping it. The three positive side fourth extensions 72, 73, 74 extend in the Y direction from the positive side third extension 71 toward the corresponding positive side G leads 31B, 32B, 33B.

[0053] Through holes are formed at the tips of the three positive electrode side fourth extensions 72, 73, 74, through which the positive electrode side G leads 31B, 32B, 33B pass. The corresponding leads 31B, 32B, 33B are inserted into the through holes and connected by solder. This electrically connects the positive electrode side fourth extensions 72, 73, 74 to the positive electrode side elements 31, 32, 33. The three positive electrode side elements 31, 32, 33 are connected in parallel.

[0054] <Negative Y Capacitor> The configuration of the negative Y capacitor 100B is the same as that of the positive Y capacitor 100A. The arrangement of the components of the negative Y capacitor 100B is dyad-symmetric with the arrangement of the corresponding components of the positive Y capacitor 100A, with the Z axis as the axis of rotation. One end of the negative first bus bar 60 is connected to the third conductive part 153 of the negative power supply bus bar 150 by welding or the like.

[0055] The negative side first bus bar 60 also has a negative side first extension 61, three negative side second extensions 62, 63, and 64, and a negative side fixed bus bar 65. The negative side fixed bus bar 65 has a tip 66. The negative side second bus bar 80 has a negative side third extension 81, three negative side fourth extensions 82, 83, and 84, and a fastened portion 85. The plate thickness of the negative side Y capacitor bus bar 40 is thinner than the plate thickness of the negative side power supply bus bar 150. The negative side first extension 61 corresponds to the positive side first extension 51. The negative side second extensions 62, 63, and 64 correspond to the positive side second extensions 52, 53, and 64. The negative side fixed bus bar 65 corresponds to the positive side fixed bus bar 55. The negative side third extension 81 corresponds to the positive side third extension 71. The negative electrode side fourth extension portions 82, 83, 84 correspond to the positive electrode side fourth extension portions 72, 73, 74. The fastened portion 85 corresponds to the fastened portion 75.

[0056] <Operations and Effects> Below, the effects of the positive Y capacitor 100A will be described as a representative example. The effects of the negative Y capacitor 100B are similar. The positive first bus bar 50 connects the positive elements 31, 32, and 33 to the positive power supply bus bar 140. The positive second bus bar 70 connects the positive elements 31, 32, and 33 to the first ground 90A. The positive fixed bus bar 55 extends from the positive first bus bar 50 toward the bottom 110 and is fixed to the bottom 110. A heat dissipation member 131 is provided between the positive fixed bus bar 55 and the bottom 110.

[0057] A high current flows through the positive power bus bar 140 due to the high voltage supplied from the high-voltage battery 2. Because a high current flows through the positive power bus bar 140, the positive power bus bar 140 generates heat and reaches a high temperature. One end of the positive power bus bar 140 is connected to the positive power bus bar 140. The positive elements 31, 32, and 33 are connected to the other end of the positive power bus bar 140. As a result, heat is transferred from the positive power bus bar 140 to the positive elements 31, 32, and 33 via the positive power bus bar 50.

[0058] In this embodiment, the positive side first bus bar 50 is provided with a positive side fixed bus bar 55. The positive side fixed bus bar 55 is fixed to the bottom 110 via a heat dissipation member 131. This allows heat to be easily transferred from the positive side fixed bus bar 55 to the bottom 110. This in turn suppresses heat transfer to the positive side elements 31, 32, and 33. This in turn suppresses a rise in temperature of the positive side elements 31, 32, and 33.

[0059] In recent years, with the increase in switching speed in inverters 11 and stricter EMC standards, more stringent noise reduction is required than ever before. To eliminate noise, Y capacitors 100 are installed in electrical equipment 10 such as power conversion devices. Generally, capacitors are required to be used at or below their heat resistance, taking into account self-heating and heat dissipation. The Y capacitor 100 is also required to be used at or below its heat resistance. In particular, the Y capacitor 100 has the lowest heat resistance of all the components installed in electrical equipment 10. For this reason, it is significant to suppress heat transfer to the Y capacitor 100 and suppress temperature rise in the Y capacitor 100.

[0060] A positive-side fixed bus bar 55 is provided between the connection portion of the positive-side first bus bar 50 with the positive-side power supply bus bar 140 and the connection portion with the positive-side elements 31, 32, and 33. This allows heat to be transferred from the positive-side fixed bus bar 55 to the bottom 110 before being transferred to the positive-side elements 31, 32, and 33. This makes it possible to efficiently suppress heat transfer from the positive-side power supply bus bar 140 to the positive-side elements 31, 32, and 33.

[0061] A plurality of elements 31, 32, 33 are lined up in the Y direction and connected in parallel to the first positive bus bar 50 and the second positive bus bar 70 via solders 34, 35. This makes it possible to suppress vibration of the first positive bus bar 50 and the second positive bus bar 70 even if the lengths of the first positive extension portion 51 and the third positive extension portion 71 are increased. Heat transfer to the plurality of positive elements 31, 32, 33 can be suppressed almost simultaneously.

[0062] The positive electrode side first bus bar 50 and the positive electrode side second bus bar 70 are disposed farther from the bottom 110 than the positive electrode side elements 31, 32, 33. The extension direction of the positive electrode side fixed bus bar 55, the extension direction of the positive electrode side leads 31A, 32A, 33A, and the extension direction of the positive electrode side G leads 31B, 32B, 33B are the same. Vibrations are absorbed by the positive electrode side fixed bus bar 55 and the heat dissipation member 131, so vibrations of the positive electrode side leads 31A, 32A, 33A and the positive electrode side G leads 31B, 32B, 33B are suppressed. Stress concentration on the solders 34, 35 is suppressed.

[0063] A flow path 117 for circulating a refrigerant is formed in the bottom 110. The refrigerant cools the Y-condenser 100. This can improve the heat dissipation effect to the bottom 110.

[0064] The thickness of the positive electrode side Y capacitor bus bar 30 is thinner than the thickness of the positive electrode side power supply bus bar 140. This makes it difficult for heat from the positive electrode side power supply bus bar 140 to be transferred to the positive electrode side Y capacitor bus bar 30. As a result, heat transfer from the positive electrode side power supply bus bar 140 to the positive electrode side elements 31, 32, 33 is suppressed.

[0065] The positive first bus bar 50 has a positive first extension 51 and positive second extensions 52, 53, and 54. One end of the positive first extension 51 is connected to the positive first bus bar 50 and extends in the X direction. One ends of the positive second extensions 52, 53, and 54 are connected to the positive first extension 51 and extend toward the positive leads 31A, 32A, and 33A. The positive second bus bar 70 has a positive third extension 71 and positive fourth extensions 72, 73, and 74. One end of the positive third extension 71 is connected to the first ground 90A and extends in the X direction. The positive electrode side fourth extensions 72, 73, 74 have one end connected to the positive electrode side third extension 71 and extend toward the positive electrode side G leads 31B, 32B, 33B. This allows the lengths of the positive electrode side second extensions 52, 53, 54 and the positive electrode side fourth extensions 72, 73, 74 to be adjusted to match the size of the positive electrode side elements 31, 32, 33, increasing the degree of freedom in design. The same applies to the negative electrode side Y capacitor 100B.

[0066] The fourth positive extensions 72, 73, and 74 of the positive Y capacitor bus bar 30 are connected to a first ground 90A. The fourth negative extensions 81, 82, and 83 of the negative Y capacitor bus bar 40 are connected to a second ground 90B. Since the positive Y capacitor bus bar 30 and the negative Y capacitor bus bar 40 are connected to the corresponding grounds 90A and 90B separately, the degree of freedom in design is increased.

[0067] Second Embodiment In the first embodiment, the configuration has been described in which the fixed bus bars 55, 65 are integrally connected to the corresponding first extension portions 51, 61 on the pole side. However, the connection positions of the fixed bus bars 55, 65 are not limited to this. For example, the fixed bus bars 55, 65 may be fixed to the corresponding third extension portions 71, 81 on the pole side.

[0068] 8 is a plan view of the electric device 10 according to the second embodiment, as viewed from the rear surface 110B. The positive electrode side fixed bus bar 55 is fixed between the connection portion of the positive electrode side third extension portion 71 with the sixth parallel portion 74 and the connection portion of the fastened portion 75. The positive electrode side fixed bus bar 55 extends in the Z direction from this position toward the bottom 110. The positive electrode side fixed bus bar 55 is fixed to the bottom 110 via a heat dissipation member 131. The negative electrode side fixed bus bar 65 is similar to the positive electrode side fixed bus bar 55. This also achieves the same effects as the first embodiment.

[0069] 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.

[0070] (Disclosure of Technical Ideas) This specification discloses multiple technical ideas described in the following multiple clauses. Some clauses may be described in a multiple dependent form, with the subsequent clause alternatively referring to the preceding clause. Furthermore, some clauses may be described in a multiple dependent form, with the subsequent clause referring to another multiple dependent clause. These multiple dependent clauses define multiple technical ideas.

[0071] (Technical Idea 1) A capacitor (100A, 100B) comprising: a power bus bar (140, 150) connected to a power source (2) and an electric component (11, 20); a capacitor (100A, 100B) connected to the power bus bar and also connected to a ground (90A, 90B); a metal casing (120) having a bottom (110) to which the capacitor is fixed and connected to the ground; and a heat dissipation member (131, 132) having insulating properties and higher thermal conductivity than air, wherein the capacitor has a capacitor bus bar (30, 40) including: an element (31, 32, 33, 41, 42, 43); a first bus bar (50, 60) connecting the element and the power bus bar; a second bus bar (70, 80) connecting the element and the ground; and a fixed bus bar (55, 65) extending from the first bus bar or the second bus bar toward the bottom and fixed to the bottom; The electrical equipment includes the heat dissipation member disposed between the fixed bus bar and the bottom.

[0072] (Technical Idea 2) The electric device according to Technical Idea 1, wherein the first bus bar extends in one direction (X) away from the power supply bus bar, and the fixed bus bar is provided between a connection portion of the first bus bar with the power supply bus bar and a connection portion of the first bus bar with the element.

[0073] (Technical Idea 3) An electrical device according to Technical Idea 2, comprising a plurality of the elements, the plurality of elements being arranged in the one direction, and the plurality of elements being connected in parallel between the first bus bar and the second bus bar via solder (34, 35, 44, 45).

[0074] (Technical Idea 4) The electrical device according to Technical Idea 3, wherein the plurality of elements are arranged closer to the bottom than the first bus bar and the second bus bar, the elements have one end leads (31A, 32A, 33A, 41A, 42A, 43A) solder-connected to the first bus bar and other end leads (31B, 32B, 33B, 41B, 42B, 43B) solder-connected to the second bus bar, and the extending direction of the one end leads and the other end leads is the same as the extending direction of the fixed bus bar.

[0075] (Technical Concept 5) The electrical device according to any one of Technical Concepts 1 to 4, wherein a refrigerant for cooling at least the condenser flows through the bottom.

[0076] (Technical Concept 6) The electric device according to any one of Technical Concepts 1 to 5, wherein the plate thickness of the capacitor bus bar is thinner than the plate thickness of the power supply bus bar.

[0077] (Technical Idea 7) The electric device according to Technical Idea 4, wherein the first bus bar has a first extension portion (51, 61) having one end connected to the power supply bus bar and extending in the one direction, and a second extension portion (52, 53, 54, 62, 63, 64) extending from the first extension portion and connected to the one end lead, and the second bus bar has a third extension portion (71, 81) having one end connected to the ground and extending in the one direction, and a fourth extension portion (72, 73, 74, 82, 83, 84) extending from the third extension portion and connected to the other end lead.

[0078] (Technical Idea 8) The electric device according to Technical Idea 7, wherein the capacitor busbars include a positive-side capacitor busbar (30) connected to the positive electrode of the power supply and a negative-side capacitor busbar (40) connected to the negative electrode of the power supply, and the fourth extension portion of the positive-side capacitor busbar and the fourth extension portion of the negative-side capacitor busbar are separate and connected to the corresponding ground, respectively.

Claims

1. A capacitor (100A, 100B) connected to a power source (2) and an electrical component (11, 20), a metal case (120) having a bottom (110) to which the capacitor is fixed and connected to the ground, and a heat dissipation member (131, 132) having insulating properties and a higher thermal conductivity than air, wherein the capacitor has an element (31, 32, 33, 41, 42, 43), a capacitor bus bar (30, 40) including a first bus bar (50, 60) connecting the element and the power source bus bar, a second bus bar (70, 80) connecting the element and the ground, and a fixed bus bar (55, 65) extending from the first bus bar or the second bus bar toward the bottom and fixed to the bottom, An electric device, wherein the heat dissipation member is provided between the fixed bus bar and the bottom.

2. The electrical device according to claim 1, wherein the first bus bar extends in one direction (X) away from the power supply bus bar, and the fixed bus bar is provided between a connection portion of the first bus bar with the power supply bus bar and a connection portion of the first bus bar with the element.

3. The electrical device according to claim 2, comprising a plurality of said elements, the plurality of said elements being arranged in line in the one direction, and the plurality of said elements being connected in parallel between the first bus bar and the second bus bar via solder (34, 35, 44, 45).

4. The electrical device of claim 3, wherein a plurality of said elements are arranged closer to the bottom than the first bus bar and the second bus bar, and said elements have one end leads (31A, 32A, 33A, 41A, 42A, 43A) solder-connected to the first bus bar and other end leads (31B, 32B, 33B, 41B, 42B, 43B) solder-connected to the second bus bar, and the extending direction of the one end leads and the other end leads is the same as the extending direction of the fixed bus bar.

5. The electric device according to any one of claims 1 to 4, wherein a refrigerant for cooling at least the condenser flows through the bottom.

6. The electrical device according to any one of claims 1 to 4, wherein the plate thickness of the capacitor bus bar is thinner than the plate thickness of the power supply bus bar.

7. The electrical device of claim 4, wherein the first bus bar has a first extension portion (51, 61) having one end connected to the power supply bus bar and extending in the one direction, and a second extension portion (52, 53, 54, 62, 63, 64) extending from the first extension portion and connected to the one end lead, and the second bus bar has a third extension portion (71, 81) having one end connected to the ground and extending in the one direction, and a fourth extension portion (72, 73, 74, 82, 83, 84) extending from the third extension portion and connected to the other end lead.

8. The electrical equipment according to claim 7, wherein the capacitor busbar comprises a positive side capacitor busbar (30) connected to the positive electrode of the power source and a negative side capacitor busbar (40) connected to the negative electrode of the power source, and the fourth extension portion of the positive side capacitor busbar and the fourth extension portion of the negative side capacitor busbar are separate and are each connected to the corresponding ground.

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