Capacitor module, inverter module and motor unit

Abstract

To provide a capacitor module, an inverter module, and a motor unit that improve the degree of freedom in the arrangement of bus bars and reduce both thermal influence and ESL.SOLUTION: In an inverter module, a capacitor module 2 for smoothing a voltage of an inverter circuit includes a supply unit 23 having connection terminals 231P to 233P and 231N to 233N to the inverter circuit, an AC unit 21 having a capacitor element 25, and a first bus bar 11, and a DC unit 22 having a second bus bar 12 for connecting a DC power supply and the supply unit. The AC unit and the DC unit are arranged side by side in the plan view and one side view of the capacitor module, and the side surfaces of the capacitor module are arranged so as to face each other in the other side view. The supply unit is located inside an outer region A that collectively surrounds both the AC unit and the DC unit in a plan view.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a capacitor module, an inverter module, and a motor unit. [Background technology]

[0002] In an inverter module, a capacitor module is used to smooth the current of an inverter circuit. The capacitor module has a capacitor element and a plurality of bus bars. The plurality of bus bars have connection terminals to the capacitor element, connection terminals to an external power supply wiring, and connection terminals to the inverter circuit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-17220 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a capacitor module that smooths the voltage of an inverter circuit, the bus bar that connects the power supply, capacitor element, and inverter circuit is prone to becoming hot. Also, to improve the performance of the capacitor module, it is necessary to reduce the equivalent series inductance (ESL). Therefore, there is a demand for a capacitor that reduces the thermal effect from the bus bar and has a reduced ESL.

[0005] In view of the above circumstances, an object of the present invention is to provide a capacitor module, an inverter module, and a motor unit that improve the freedom of bus bar arrangement and reduce both the thermal effect and ESL. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided a capacitor module for smoothing a voltage of an inverter circuit, the capacitor module comprising: a supply section having a connection terminal to the inverter circuit; a capacitor element; and a plate-shaped first bus bar connecting the capacitor element and the supply section. AC component reduction and a DC section having a plate-shaped second bus bar that connects a DC power source and the supply section. AC component reduction The supply unit and the DC unit are arranged side by side in a plan view and one side view of the capacitor module, and are arranged with their side surfaces facing each other in the other side view. AC component reduction The DC portion is located inside an outer region that collectively surrounds both the DC portion and the DC portion. The second busbars include a positive side second busbar and a negative side second busbar, and each of the positive side second busbar and the negative side second busbar consists of two busbars, a power supply side busbar and a supply side busbar, and each of the two power supply side busbars has a connection terminal with a DC power supply and a connection terminal with the supply side busbar, and each of the two power supply side busbars has a portion between the two connection terminals where each plate surface extends along the direction in which the AC component reduction portion and the DC portion are arranged. Effect of the Invention

[0007] According to one aspect of the present invention, there is provided a capacitor module, an inverter module, and a motor unit in which both the thermal effect and the ESL are reduced. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram that illustrates a schematic vertical cross section of an inverter module. [Diagram 2] FIG. 2 is a circuit block diagram of the inverter module. [Diagram 3] FIG. 3 is a perspective view of the capacitor module as viewed obliquely from above. [Figure 4] FIG. 4 is a side view of the capacitor module. [Diagram 5] FIG. 5 is a perspective view of the capacitor module as viewed obliquely from below. [Figure 6] FIG. 6 is a perspective view showing the internal structure of the capacitor module. [Figure 7] FIG. 7 is a plan view of the capacitor module. [Figure 8] FIG. 8 is a perspective view showing the positive bus bar out of first bus bar 11 and the second bus bar. [Figure 9]FIG. 9 is a perspective view showing the negative bus bar out of the first bus bar and the second bus bar. [Figure 10] FIG. 10 is a side view of the capacitor element, the first bus bar, and the second bus bar. [Figure 11] FIG. 11 is a cross-sectional view of the capacitor module in a portion including a magnetic core and a filter capacitor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An inverter module and a capacitor module according to embodiments of the present invention will now be described with reference to the drawings. In the drawings referred to in the following description, an XYZ coordinate system is appropriately shown as a three-dimensional Cartesian coordinate system. In the XYZ coordinate system, the up-down direction in FIG. 1 is defined as the Z-axis direction. The +Z direction is the upper side (opposite the direction of gravity), and the -Z direction is the lower side (direction of gravity). The X-axis direction is a direction perpendicular to the Z-axis direction, and indicates the direction in which the DC and AC parts in the capacitor module are aligned. The Y-axis direction is a direction perpendicular to both the X-axis and Z-axis directions. In this specification, "plan view" means viewing the inverter module and the capacitor module from the Z-axis direction. Note that the orientation of the capacitor module in this specification is an example and does not limit the orientation in which the capacitor module is actually attached.

[0010] Fig. 1 is an explanatory diagram showing a schematic vertical cross section of an inverter module, and Fig. 2 is a circuit block diagram of the inverter module. As shown in FIG. 1, an inverter module 1 of this embodiment includes a capacitor module 2, a power module 3, a control module 4 including a control board 40 and a drive board 41, a housing 7, and a coolant flow path 8.

[0011] The housing 7 accommodates therein the capacitor module 2, the power module 3, the control module 4, and the refrigerant flow path 8. The components of the inverter module 1 are arranged in a stacked manner in the vertical direction (Z-axis direction) inside the housing 7. Specifically, from the bottom, the control board 40, the capacitor module 2, the drive board 41, the power module 3, and the refrigerant flow path 8 are stacked in this order. Note that this arrangement is just one example, and the capacitor module 2 and the power module 3 may also be arranged side by side on the XY plane.

[0012] 2, the inverter module 1 is connected between a DC power supply 6 and a motor 5. The inverter module 1 converts a DC current supplied from the DC power supply 6 into an AC current, and supplies the AC current to the motor 5. In this embodiment, the motor 5 is a three-phase motor. The motor 5 may be a multi-phase motor having four or more phases. The motor 5 is connected to the power module 3 of the inverter module 1. The DC power supply 6 is, for example, a secondary battery or an electric double layer capacitor. The DC power supply 6 is connected to the connection terminals 121P and 121N for external power supplies of the inverter module 1. It should be noted that a generator may be connected in place of the motor 5. In this case, the inverter module 1 converts the power input from the generator into DC power, and charges the DC power supply 6.

[0013] The power module 3 has an inverter circuit 31 made up of a plurality of switching elements 30. In this embodiment, the switching elements 30 are IGBTs (Insulated Gate Bipolar Transistors). The switching elements 30 may be power semiconductor elements other than IGBTs. The switching elements 30 may be power MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), SiC-MOSFETs, or GaN-MOSFETs.

[0014] The inverter circuit 31 is a three-phase inverter configured with six switching elements 30. That is, the inverter circuit 31 has arms configured with two switching elements for three phases corresponding to the U phase, V phase, and W phase. The midpoint of each arm is connected to the motor 5. Positive electrode terminals of the three arms are connected to positive electrode supply terminals 231P, 232P, 233P of the capacitor module 2. Negative electrode terminals of the three arms are connected to negative electrode supply terminals 231N, 232N, 233N of the capacitor module 2.

[0015] The power module 3 has a cooling member 3A shown in FIG. 1. The cooling member 3A cools the inverter circuit 31. A part of the cooling member 3A is located in a refrigerant flow path 8. The refrigerant flow path 8 is provided in the housing 7 or the power module 3. Heat of the inverter circuit 31 is dissipated to the refrigerant by contact between the refrigerant flowing through the refrigerant flow path 8 and the cooling member 3A. The refrigerant flowing through the refrigerant flow path 8 is, for example, LLC (ethylene glycol aqueous solution). The refrigerant may be water. The inverter module 1 may also be provided with a mechanism for cooling the capacitor module 2.

[0016] The control module 4 includes a control board 40 and a drive board 41 . The control board 40 generates a control signal for controlling the switching of the multiple switching elements 30 of the inverter circuit 31. The drive board 41 generates drive power for the switching elements 30 based on the control signal input from the control board 40.

[0017] The control module 4 is connected to a higher-level device such as a vehicle control device via a controller area network (CAN). The control module 4 executes drive control of the motor 5 via the inverter circuit 31 based on a control signal input from the higher-level device.

[0018] 2, the capacitor module 2 is connected to a DC power source 6 and a power module 3. Hereinafter, the capacitor module 2 will be described in detail with reference to FIG. 3 and subsequent figures.

[0019] FIG. 3 is a perspective view of the capacitor module 2 as viewed obliquely from above. FIG. 4 is a side view of the capacitor module 2. FIG. 5 is a perspective view of the capacitor module 2 as viewed obliquely from below. FIG. 6 is a perspective view showing the internal structure of the capacitor module 2. FIG. 7 is a plan view of the capacitor module 2. FIG. 8 is a perspective view showing the positive busbar of the first busbar 11 and the second busbar. FIG. 9 is a perspective view showing the negative busbar of the first busbar and the second busbar. FIG. 10 is a side view of the capacitor element, the first busbar, and the second busbar.

[0020] As shown in FIGS. 3 to 7, the capacitor module 2 has an AC section 21, a DC section 22, and a supply section . The AC section 21 has five capacitor elements 15 and a plate-shaped first bus bar 11 that connects the five capacitor elements 15 and the supply section 23. In the present embodiment, the five capacitor elements 15 are aligned along the Y-axis direction. The AC section 21 as a whole has a longitudinal shape in the Y-axis direction. The number of capacitor elements 15 in the AC section 21 is not limited to five, and may be any number equal to or less than five or equal to or greater than six.

[0021] The five capacitor elements 15 have electrodes on their upper and lower surfaces. The first bus bar 11 has a positive first bus bar 11P connected to the electrode on the upper surface of the capacitor element 15, and a negative first bus bar 11N connected to the electrode on the lower surface of the capacitor element 15.

[0022] As shown in Fig. 8 and Fig. 10, the positive electrode first busbar 11P has a capacitor side terminal 111P extending in the Y-axis direction across the upper surfaces of the five capacitor elements, three wiring parts 112P extending upward from the end of the capacitor side terminal 111P on the DC section 22 side (+X side), and three supply side terminals 113P extending horizontally from the end of the upper end of the three wiring parts 112P on the DC section 22 side toward the DC section 22 side. The width of the wiring parts 112P in the Y-axis direction is larger than the width of the supply side terminal 113P in the Y-axis direction. The supply side terminal 113P has a through hole penetrating the supply side terminal 113P in the plate thickness direction (Z-axis direction). The three supply side terminals 113P, together with three supply side terminals 125P of the positive electrode second busbar 12P described later, constitute three supply terminals 231P, 232P, 233P of the supply unit 23.

[0023] As shown in Fig. 9 and Fig. 10, the negative electrode first bus bar 11N has a capacitor side terminal 111N extending in the Y-axis direction across the upper surfaces of the five capacitor elements, a wiring portion 112N extending upward from an end portion of the capacitor side terminal 111N on the DC section 22 side (+X side), and three supply side terminals 113N extending horizontally from an end portion of the wiring portion 112N on the DC section 22 side toward the DC section 22 side from the upper end of the wiring portion 112N. The wiring portion 112N has a main body portion 112aN extending upward with a width equivalent to the Y-axis direction width of the capacitor side terminal 111N, and three branch portions 112bN extending upward from the upper end of the main body portion 112aN. The supply side terminals 113N extend from the tips of the branch portions 112bN. The Y-axis direction width of the branch portions 112bN is larger than the Y-axis direction width of the supply side terminals 113N. The supply terminal 113N has a through hole penetrating the supply terminal 113N in the plate thickness direction (Z-axis direction). The three supply terminals 113N, together with three supply terminals 125N of the negative electrode second bus bar 12N described later, constitute three supply terminals 231N, 232N, 233N of the supply unit 23.

[0024] 10, positive side first busbar 11P and negative side first busbar 11N of first busbar 11 are arranged close to each other in the X-axis direction at portions (wiring portions 112P, 112N) extending upward toward supply portion 23. That is, first busbar 11 has closely arranged portion 11A between capacitor element 15 and supply portion 23 where positive side first busbar 11P and negative side first busbar 11N overlap and are close to each other in the plate thickness direction. With this configuration, the directions of currents flowing between capacitor element 15 and supply unit 23 are opposite to each other in wiring portion 112P and wiring portion 112N, so that the parasitic inductance of positive side first bus bar 11P and the parasitic inductance of negative side first bus bar 11N cancel each other out. This reduces the ESL (equivalent series inductance) of capacitor element 15.

[0025] In the closely arranged portion 11A shown in Fig. 10, an insulating sheet such as insulating paper may be sandwiched between the wiring portion 112P and the wiring portion 112N. The thickness of the insulating sheet is, for example, 0.05 mm or more and less than 1 mm. The thickness of the insulating sheet may be 0.1 mm or more. The thickness of the insulating sheet may be 0.7 mm or less, or 0.5 mm or less. That is, positive electrode first bus bar 11P and negative electrode first bus bar 11N may be configured to face each other at positions close to each other with an insulating sheet interposed therebetween that is thinner than the plate thickness of the first bus bar. With this configuration, wiring portion 112P and wiring portion 112N can be brought as close to each other as the thickness of the insulating sheet. By bringing the two as close as possible to each other, the ESL reduction effect can be increased.

[0026] The DC section 22 has a plate-shaped second bus bar 12 that connects the DC power supply 6 and the supply section 23. The second bus bar 12 has a positive side second bus bar 12P connected to the positive side of the DC power supply 6, and a negative side second bus bar 12N connected to the negative side of the DC power supply 6, as shown in Fig. 6 and Fig. 7.

[0027] As shown in Figs. 8 and 10, the positive electrode side second bus bar 12P is made up of two bus bars, a power supply side bus bar 221P and a supply side bus bar 222P. Power supply side bus bar 221P has connection terminal 121P for connection with DC power supply 6, and connection terminal 122P for connection with supply side bus bar 222P. In power supply side bus bar 221P, connection terminal 121P and connection terminal 122P are connected via wiring portion 123P.

[0028] Wiring portion 123P extends along the Y-axis direction from connection terminal 121P located at the -Y side end of DC section 22 to connection terminal 122P located at the +Y side end of DC section 22. Wiring portion 123P is made up of a plurality of wiring portions 123aP to 123eP.

[0029] The wiring portion 123aP extends downward from the end of the connection terminal 121P on the side opposite to the AC section 21 (+X side). The wiring portion 123bP extends from the lower end of the wiring portion 123aP to the +Y side and reaches the center of the DC section 22 in the Y-axis direction. The wiring portion 123cP extends upward from the end of the wiring portion 123bP on the +Y side. The wiring portion 123dP extends to the +Y side from the upper end of the wiring portion 123cP. The wiring portion 123eP extends from the end of the wiring portion 123dP on the +Y side to the +X side and is connected to the connection terminal 122P.

[0030] Among the wiring portions 123aP to 123eP, the wiring portions 123bP, 123cP, and 123dP have their plate surfaces extending in the vertical direction (Z-axis direction) or the Y-axis direction. That is, the plate surfaces of the wiring portions 123bP, 123cP, and 123dP extend along the direction in which the AC portions 21 and the DC portions 22 are arranged (X-axis direction). That is, the power supply side bus bar 221P has a portion between the two connection terminals 121P and 122P whose plate surface extends along the direction in which the AC portions 21 and the DC portions 22 are arranged (X-axis direction). According to this configuration, since the plate surfaces of wiring portions 123bP, 123cP, and 123dP do not face AC unit 21 (-X side), heat dissipated from those plate surfaces is less likely to flow toward AC unit 21. As a result, heat from power supply side bus bar 221P, which becomes hot due to the large current flowing therethrough, is less likely to be transmitted to capacitor element 15.

[0031] Supply-side busbar 222P has connection terminal 124P with power supply-side busbar 221P, and three supply-side terminals 125P connected to supply unit 23. Connection terminal 124P is fixed with screws to connection terminal 122P of power supply-side busbar 221P. In supply-side busbar 222P, connection terminal 124P and the three supply-side terminals 125P are connected via wiring unit 126P.

[0032] The wiring part 126P extends in the X-axis direction in a plan view from a connection terminal 124P located at the end of the DC part 22 opposite to the AC part 21 (+X side), toward a supply side terminal 125P located in the supply part 23. The wiring part 126P is made up of a plurality of wiring portions 126aP to 126dP.

[0033] The wiring portion 126aP extends downward from the end of the connection terminal 124P on the AC unit 21 side (-X side). The wiring portion 126bP extends from the lower end of the wiring portion 126aP toward the AC unit 21 side. The wiring portion 126cP extends upward and toward the connection terminal 121P side (-Y side) from the end of the wiring portion 126bP on the AC unit 21 side. That is, the wiring portion 126cP spreads along the Y-axis direction and the Z-axis direction. The wiring portion 126dP extends upward from three points on the upper end of the wiring portion 126cP, and each is connected to the supply side terminal 125P.

[0034] The supply terminal 125P has a through hole penetrating the supply terminal 125P in the plate thickness direction (Z-axis direction). The three supply terminals 125P, together with the three supply terminals 113P of the positive electrode first bus bar 11P, constitute three supply terminals 231P, 232P, 233P of the supply unit 23.

[0035] As shown in Figs. 9 and 10, the negative electrode side second bus bar 12N is made up of two bus bars, a power supply side bus bar 221N and a supply side bus bar 222N. The power supply side bus bar 221N has a connection terminal 121N to the DC power supply 6 and a connection terminal 122N to the supply side bus bar 222N. In the power supply side bus bar 221N, the connection terminal 121N and the connection terminal 122N are connected via a wiring portion 123N.

[0036] The wiring portion 123N extends along the Y-axis direction from a connection terminal 121N located at the -Y side end of the DC portion 22 toward a connection terminal 122N located at the +Y side end of the DC portion 22. The wiring portion 123N is made up of a plurality of wiring portions 123aN to 123dN.

[0037] The wiring portion 123aN extends downward from the end of the connection terminal 121N on the AC unit 21 side (-X side). The wiring portion 123bN extends from the lower end of the wiring portion 123aN to the +Y side and reaches the center of the DC portion 22 in the Y-axis direction. The wiring portion 123cN extends upward from the end of the wiring portion 123bN on the +Y side. The wiring portion 123dN extends from the upper end of the wiring portion 123cN to the +Y side and is connected to the end of the connection terminal 122N on the AC unit 21 side (-X side).

[0038] Among the wiring portions 123aN to 123dN, the wiring portions 123bN, 123cN, and 123dN have their plate surfaces extending in the vertical direction (Z-axis direction) or the Y-axis direction. That is, the plate surfaces of the wiring portions 123bN, 123cN, and 123dN extend along the direction in which the AC portions 21 and the DC portions 22 are arranged (X-axis direction). That is, the power supply side bus bar 221N has a portion between the two connection terminals 121N and 122N whose plate surface extends along the direction in which the AC portions 21 and the DC portions 22 are arranged (X-axis direction). According to this configuration, the plate surfaces of the wiring portions 123bN, 123cN, and 123dN do not face the AC unit 21 side (-X side), so that heat dissipated from those plate surfaces is less likely to flow toward the AC unit 21. As a result, the heat of the power supply side bus bar 221N, which becomes hot due to the large current flowing therethrough, is less likely to be transmitted to the capacitor element 15.

[0039] Supply-side bus bar 222N has a connection terminal 124N with power supply-side bus bar 221N, and three supply-side terminals 125N connected to supply unit 23. Connection terminal 124N is fixed to power supply-side bus bar 221N with screws. In supply-side bus bar 222N, connection terminal 124N and the three supply-side terminals 125N are connected via wiring unit 126N.

[0040] The wiring part 126N extends in the X-axis direction in a plan view from a connection terminal 124N located at the end of the DC part 22 opposite to the AC part 21 (+X side), toward a supply side terminal 125N located in the supply part 23. The wiring part 126N is made up of a plurality of wiring portions 126aN to 126dN.

[0041] The wiring portion 126aN extends downward from the end of the connection terminal 124N on the AC unit 21 side (-X side). The wiring portion 126bN extends from the lower end of the wiring portion 126aN toward the AC unit 21 side. The wiring portion 126cN extends upward and toward the connection terminal 121N side (-Y side) from the end of the wiring portion 126bN on the AC unit 21 side. That is, the wiring portion 126cN spreads along the Y-axis direction and the Z-axis direction. The wiring portion 126dN extends upward from three points on the upper end of the wiring portion 126cN, and each is connected to the supply side terminal 125N.

[0042] The supply terminal 125N has a through hole penetrating the supply terminal 125N in the plate thickness direction (Z-axis direction). The three supply terminals 125N, together with the three supply terminals 113N of the negative electrode first bus bar 11N, constitute three supply terminals 231N, 232N, 233N of the supply unit 23.

[0043] 10, in second bus bar 12, supply-side bus bars 222P, 222N are also arranged adjacent to each other in the plate thickness direction near supply portion 23. More specifically, in closely arranged portion 12A shown in Fig. 10, wiring portion 126cP of wiring portion 126P and wiring portion 126cN of wiring portion 126N are arranged adjacent to each other in the plate thickness direction, and wiring portion 126dP and wiring portion 126dN are arranged adjacent to each other in the plate thickness direction.

[0044] In the closely arranged section 12A as well, a thin insulating sheet such as insulating paper may be sandwiched between the supply-side busbars 222P, 222N. That is, the positive side second busbar 12P and the negative side second busbar 12N may be configured to face each other at positions close to each other via an insulating sheet that is thinner than the plate thickness of the second busbar 12. With this configuration, the distance between the busbars can be reduced, making it easier to miniaturize the DC section 22. Note that the insulating sheet may be disposed between the bus bars at a position other than the above, where the bus bars are close to each other.

[0045] As shown in FIGS. 6 and 7, the capacitor module 2 has a magnetic core 27 and two filter capacitors 28 in the DC section 22. FIG. 11 is a cross-sectional view of the capacitor module 2 in a portion including the magnetic core 27 and the filter capacitor 28.

[0046] The magnetic core 27 is made of a cylindrical magnetic material. The magnetic core 27 is, for example, a ferrite core. The magnetic core 27 is arranged to extend in the Y-axis direction. The wiring portions 123bP, 123bN of the power supply side bus bars 221P, 221N are passed through an inner hole of the magnetic core 27. The power supply side bus bars 221P, 221N are bent in a crank shape as shown in FIG. 11. The magnetic core 27 is arranged between the connection terminals 121P, 121N and the wiring portions 123cP, 123cN, which are bent portions in a crank shape, in the Y-axis direction.

[0047] Filter capacitors 28 are arranged to be sandwiched in the vertical direction between wiring portions 123dP, 123dN of power supply side bus bars 221P, 221N and wiring portions 126bP, 126bN of supply side bus bars 222P, 222N. One filter capacitor 28 is connected between supply side bus bar 222P and ground, and one filter capacitor 28 is connected between supply side bus bar 222N and ground.

[0048] In the capacitor module 2 of this embodiment, the magnetic core 27 and the filter capacitor 28 are arranged side by side in a plan view with their side surfaces facing each other. With this configuration, the magnetic core 27 and the filter capacitor 28 can be installed in a relatively narrow space. This makes it possible to implement noise countermeasures for the DC section 22 while preventing the capacitor module 2 from becoming larger.

[0049] Furthermore, in the capacitor module 2 of this embodiment, the power supply side bus bars 221P, 221N are bent in a crank shape when viewed from the side, and the magnetic core 27 and the filter capacitor 28 are arranged side by side with the bent portions of the power supply side bus bars 221P, 221N in between. With this configuration, the power supply side bus bars 221P, 221N, the magnetic core 27, and the filter capacitor 28 can be arranged efficiently in a narrower space.

[0050] The supply unit 23 has six supply terminals 231P, 232P, 233P, 231N, 232N, and 233N to the inverter circuit 31. Positive electrode supply terminals 231P, 232P, 233P are constituted by three supply terminals 113P of positive electrode first bus bar 11P and three supply terminals 125P of positive electrode second bus bar 12P. The negative supply terminals 231N, 232N, 233N are constituted by three supply terminals 113N of the negative first bus bar 11N and three supply terminals 125N of the negative second bus bar 12N.

[0051] 10 and 7, first busbar 11 is arranged only on the capacitor element 15 side (-X side) from supply portion 23, and second busbar 12 is arranged only on the opposite side (+X side) from capacitor element 15 from supply portion 23. That is, first busbar 11 and second busbar 12 overlap each other only at supply portion 23 in a plan view. According to this configuration, the number of locations where first bus bar 11 and second bus bar 12 are close to each other is reduced, so that heat from second bus bar 12 connected to DC power supply 6 is less likely to be transmitted to first bus bar 11. As a result, heat is also less likely to be transmitted to capacitor element 15 connected to first bus bar 11.

[0052] In the capacitor module 2 of this embodiment, the AC section 21 and the DC section 22 are arranged side by side in a plan view (Z-axis direction view) with their side surfaces facing each other, as shown in Figs. 6 and 7. In this embodiment, the AC section 21 and the DC section 22 are arranged along the X-axis direction. That is, the AC section 21 and the DC section 22 are arranged side by side in a plan view (Z-axis direction view) and one side view (Y-axis direction view). The side surface of the AC section 21 facing the +X side and the side surface of the DC section 22 facing the -X side face each other in the X-axis direction. That is, the AC section 21 and the DC section 22 are arranged with their side surfaces facing each other in a direction along the other side view (X-axis direction). The supply section 23 is located between the AC section 21 and the DC section 22 in a plan view. Specifically, in a region extending along the Y-axis direction between AC section 21 and DC section 22, supply terminals 231P, 231N, 232P, 232N, 233P, and 233N are arranged in a line in the Y-axis direction.

[0053] According to the above configuration, the horizontal distance (X-axis direction) between power supply side bus bars 221P, 221N, which become hot due to the flow of a large current, and capacitor elements 15, which should be kept away from high temperatures, can be increased by the amount of supply unit 23 disposed therebetween. This makes it possible to prevent the heat from power supply side bus bars 221P, 221N from being transferred to capacitor elements 15. This makes it possible to prevent the electrical characteristics of capacitor elements 15 from changing or their lifespan from being shortened due to high temperatures.

[0054] Furthermore, by arranging AC section 21 and DC section 22 side by side and supply section 23 between them, the shapes of the busbars included in supply section 23 and the busbars included in the DC section can be freely designed and connected to supply section 23. Therefore, the shapes of the DC section and the AC section are not restricted by each other, and a busbar design that can reduce ESL can be performed.

[0055] The position of the supply unit 23 is not limited to between the AC unit 21 and the DC unit 22. The supply unit 23 may be located at a position overlapping with the AC unit 21 or the DC unit 22 in a plan view. Alternatively, the supply unit 23 may be located at a position overlapping with both the AC unit 21 and the DC unit 22. That is, the position of the supply unit 23 can be changed as long as it is within the range of the outer shape region A shown in FIG. 7. The supply unit 23 can be configured to be located inside the outer shape region A that surrounds both the AC unit 21 and the DC unit 22 together in a plan view. According to this configuration, the supply unit 23 is not located outside the AC unit 21 or outside the DC unit in a plan view, so that the area where the AC unit 21 and the DC unit 22 overlap in a plan view can be reduced. This makes it possible to suppress the transfer of heat from the high-temperature parts of the second bus bar 12 (power supply side bus bars 221P, 221N) to the first bus bar 11 and the capacitor element 15.

[0056] 3, the capacitor module 2 of this embodiment has a resin member 24 that holds the AC unit 21 and the DC unit 22. The resin member 24 surrounds the side and bottom surfaces of the AC unit 21 and the DC unit 22. In other words, the resin member 24 is a housing for the capacitor module 2. The resin member 24 has a shape that opens upward, but may be provided with a lid that covers the AC unit 21 and the DC unit 22 from above. Alternatively, a sealing resin may be poured from the upper surface side of the AC unit 21 and the DC unit 22 to resin-seal the AC unit 21 and the DC unit 22.

[0057] The resin member 24 has a fixing portion 25 on its outer periphery in a plan view to be fixed to an external device. The external device is, for example, the housing 7 of the inverter module 1 shown in Fig. 1. This configuration makes it easy to mount the capacitor module 2 on the inverter module 1 or the like.

[0058] An aluminum noise shielding member 26 is attached to the lower surface of the resin member 24. The noise shielding member 26 is a plate extending along a plane (XY plane) perpendicular to the up-down direction. The noise shielding member 26 covers the AC section 21, the DC section 22, and the supply section 23 from the lower surface side. By providing the noise shielding member 26, it is possible to suppress the propagation of noise in the inverter module 1 in the up-down direction.

[0059] 1, in this embodiment, the drive board 41 and the power module 3 are disposed on the upper surface side of the capacitor module 2, and the control board 40 is disposed on the lower surface side of the capacitor module 2. In this configuration, the noise shielding member 26 is disposed between the control board 40 and the drive board 41 and the power module 3, so that noise generated on the drive board 41 side can be suppressed from being transmitted to the control board 40.

[0060] 3 and 4, the capacitor module 2 has a plurality of cylindrical screw bosses 241 protruding downward from the lower surface of the resin member 24. In the present embodiment, the resin member 24 has eleven screw bosses 241. The screw bosses 241 pass through through holes provided in the noise shielding member 26 and protrude downward beyond the noise shielding member 26.

[0061] The lower ends of the eleven screw bosses 241 are positioned on one plane. As shown in Fig. 4, the control board 40 can be installed by screwing to the screw bosses 241. By fixing the control board 40 to the screw bosses 241 whose lower ends are aligned, the control board 40 can be installed parallel to the lower surface of the capacitor module 2.

[0062] The control board 40 has a flat surface 40a on the upper surface side that faces the capacitor module 2 in the up-down direction. The control board 40 is also installed at a position that overlaps with both the AC unit 21 and the DC unit 22 in a plan view. That is, on the lower surface of the capacitor module 2 in this embodiment, a member (control board 40) that has a flat surface 40a that faces the lower surface of the capacitor module 2 and overlaps with at least a portion of both the AC unit 21 and the DC unit 22 in a plan view can be installed.

[0063] According to the above configuration, the capacitor module 2 and a component (e.g., the control board 40) installed on the underside of the capacitor module 2 can be arranged compactly in the vertical direction. The internal space of the housing 7 of the inverter module 1 can be utilized efficiently. The inverter module 1 can be easily made smaller. Since the noise shielding member 26 and the control board 40 can be arranged at a uniform interval, the noise shielding function of the noise shielding member 26 can be effectively exerted.

[0064] The inverter module 1 of this embodiment is mounted on a motor unit (not shown). The motor module is mounted on a vehicle. As described above, the inverter module of this embodiment is equipped with a capacitor inverter with reduced thermal effects and ESL, and therefore has high performance and is resistant to failures. Therefore, the motor unit equipped with it can also withstand large currents and have a long life. [Explanation of symbols]

[0065] REFERENCE SIGNS LIST 1... inverter module, 2... capacitor module, 6... DC power supply, 11... first bus bar, 11P... positive electrode side first bus bar, 11N... negative electrode side first bus bar, 11A... adjacent arrangement portion, 12... second bus bar, 12P... positive electrode side second bus bar, 12N... negative electrode side second bus bar, 15... capacitor element, 21... AC portion, 22... DC portion, 23... supply portion, 24... resin member, 25... fixing portion, 26... noise shielding member, 27... magnetic core, 28... filter capacitor, 31... inverter circuit, 40a... flat surface, 221N, 221P... power supply side bus bar, 222N, 222P... supply side bus bar, A... outer shape area

Claims

1. A capacitor module for smoothing a voltage of an inverter circuit, A supply unit having a connection terminal for the inverter circuit; an AC component reducing unit having a capacitor element and a plate-shaped first bus bar connecting the capacitor element and the supply unit; a DC section having a plate-shaped second bus bar that connects a DC power source and the supply section; Equipped with the AC component reduction unit and the DC unit are arranged side by side in a plan view and one side view of the capacitor module, and are arranged with their side surfaces facing each other in the other side view; the supply unit is located inside an outer shape region that collectively surrounds both the AC component reduction unit and the DC unit in a plan view, the second bus bars include a positive electrode side second bus bar and a negative electrode side second bus bar, the positive electrode side second bus bar and the negative electrode side second bus bar each include two bus bars, a power supply side bus bar and a supply side bus bar; each of the two power source side bus bars has a terminal for connection to a DC power source and a terminal for connection to the supply side bus bar; each of the two power supply side bus bars has a portion between the two connection terminals, the portion having a plate surface extending along a direction in which the AC component reducing portion and the DC portion are arranged; Capacitor module.

2. The supply unit is located between the AC component reduction unit and the DC unit in a plan view. The capacitor module according to claim 1 .

3. In a plan view, the first bus bar and the second bus bar overlap each other only at the supply portion. The capacitor module according to claim 2 .

4. A magnetic core attached to the second bus bar; a first filter capacitor and a second filter capacitor each connected to the second bus bar; In a plan view, the magnetic core, the first filter capacitor, and the second filter capacitor are arranged in this order along the supply portion. The capacitor module according to claim 1 .

5. the second bus bars include a positive electrode side second bus bar and a negative electrode side second bus bar, the positive electrode side second bus bar and the negative electrode side second bus bar each include two bus bars, a power supply side bus bar and a supply side bus bar; the power supply bus bar is bent in a crank shape in a side view, The magnetic core and the filter capacitor are arranged side by side with the bent portion of the power supply side bus bar in between. The capacitor module according to claim 4 .

6. a resin member that holds the AC component reducing portion and the DC portion; and an aluminum noise shielding member attached to the resin member. The capacitor module according to claim 4 .

7. The supply unit is disposed on an upper surface of the capacitor module; A member having a flat surface facing the lower surface of the capacitor module and overlapping at least a portion of both the AC component reducing section and the DC section in a plan view can be installed on the lower surface of the capacitor module. The capacitor module according to claim 4 .

8. A fixing portion that is fixed to an external device. The capacitor module according to claim 4 .

9. the first bus bar includes a positive electrode side first bus bar and a negative electrode side first bus bar, the positive electrode side first bus bar and the negative electrode side first bus bar face each other at positions close to each other via an insulating sheet having a thickness thinner than that of the first bus bar; The capacitor module according to claim 4 .

10. The second bus bar includes a positive electrode side second bus bar and a negative electrode side second bus bar, the positive electrode side second bus bar and the negative electrode side second bus bar face each other at positions close to each other via an insulating sheet having a thickness thinner than that of the second bus bar; The capacitor module according to claim 4 .

11. An inverter module comprising: the capacitor module according to claim 4; and an inverter circuit.

12. A motor unit comprising the inverter module according to claim 1.

13. A motor unit equipped with an inverter module as described in claim 4.

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