Vehicle drive systems

Abstract

To reduce a mounting space for a Y capacitor.SOLUTION: There is disclosed a vehicle driving device including: a power conversion device that supplies power to a rotary electric machine; a case that stores the power conversion device; a Y capacitor stored in the case and electrically connected between the power conversion device and a power source; a first terminal that electrically connects the Y capacitor to a positive electrode side of the power source; a second terminal that electrically connects the Y capacitor to a negative electrode side of the power source; and a third terminal that electrically connects the Y capacitor to a ground. The first terminal and the second terminal each have a fastening surface having a first direction as a normal direction and being a surface for fastening a terminal from the power source side. The third terminal has a fastening surface having a second direction, which is different from the first direction, as a normal direction and being a surface for fastening a member having a ground potential.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a vehicle drive device.

Background Art

[0002] A technique of arranging two noise removal capacitor elements (Y capacitors) together with a power conversion device in a case is known.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional technology as described above, the fastening surfaces of a plurality of connection terminals related to the Y capacitor all face in the vertical direction, and it is difficult to reduce the mounting space of the Y capacitor.

[0005] Therefore, on one side, the present disclosure aims to reduce the mounting space related to the Y capacitor.

Means for Solving the Problems

[0007] In one respect, this disclosure makes it possible to reduce the mounting space required for the Y capacitor. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic cross-sectional view of a vehicle drive system according to this embodiment. [Figure 2] This figure shows an example of an electrical circuit including a power converter. [Figure 3] This is a perspective view of the mounting structure of a Y capacitor. [Figure 4] This is an exploded perspective view showing a portion of Figure 3. [Figure 5] This is an exploded perspective view showing a further portion of Figure 4. [Figure 5A] This is an exploded perspective view showing the three types of terminals (P terminal, N terminal, and GN terminal). [Figure 6] This is a diagram illustrating the three types of terminals of a Y-capacitor using comparative examples. [Figure 7] This is a front view of the mounting structure of the Y capacitor, viewed in the Y direction. [Figure 8] This is a plan view of the mounting structure of the Y capacitor, viewed in the Z direction. [Modes for carrying out the invention]

[0009] The following describes each embodiment in detail with reference to the attached drawings. Note that the dimensional ratios in the drawings are merely examples and are not exhaustive. Furthermore, some shapes and other details in the drawings may be exaggerated for illustrative purposes.

[0010] FIG. 1 is a schematic cross-sectional view of a vehicle drive device 100 according to this embodiment. In FIG. 1 and the like, a coordinate system (right-handed coordinate system) representing three orthogonal axial directions is shown. In the following description, the Z direction corresponds to the vertical direction in the usage state of the vehicle drive device 100, that is, the vertical direction when the vehicle drive device 100 is arranged in its usage state orientation. And, assuming that the positive side of the Z direction corresponds to the upper side and the negative side corresponds to the lower side, the description will be made.

[0011] The vehicle to which the vehicle drive device 100 is applied may be any vehicle provided with a rotating electric machine 1 as a drive source, and may be an electric vehicle, a hybrid vehicle, or the like.

[0012] The vehicle drive device 100 includes a case 2 that houses various components. In this embodiment, the case 2 houses the rotating electric machine 1, the power conversion device 80, and the like.

[0013] The case 2 may be formed by a combination of a plurality of case members. In the following description, as an example, the case 2 is assumed to be formed by joining a case member 200, a cover member 201, and an inverter cover member 203. Note that the joining method may be fastening with bolts or the like.

[0014] The case 2 includes a motor case portion 21 and an inverter case portion 24 in an integrated form. Here, the "integrated form" includes a form integrated with fastening members such as bolts and a form integrated by integral molding (for example, casting).

[0015] In a modification, other drive elements may be housed in the case 2. For example, a speed reduction mechanism, a differential gear device, or the like that can be arranged between the rotating electric machine 1 and the wheels may be housed in the case 2.

[0016] The motor case portion 21 forms a motor housing chamber S1 for housing the rotating electric machine 1. The motor case portion 21 may have a cylindrical form corresponding to the outer shape of the rotating electric machine 1 (for example, a form with a circular cross-section or a polygonal cross-section). The rotating electric machine 1 functions as a drive source of the vehicle. The rotating electric machine 1 may be, for example, a three-phase motor and may be an inner rotor type.

[0017] Note that it is not necessary for the entire outer peripheral portion of the motor case portion 21 to be closed. For example, in a configuration where a speed reduction mechanism or a differential gear device (not shown) is arranged in the case 2, the space in the motor case portion 21 may communicate with the space where the output shaft between the wheel and the differential gear device is arranged.

[0018] The inverter case portion 24 is arranged on the upper part or the like of the motor case portion 21. The inverter case portion 24 forms an inverter housing chamber S4 for housing the power conversion device 80.

[0019] In this embodiment, a power connector 10 is attached to the inverter case portion 24. The power connector 10 supplies the power from the power source BA to the rotating electric machine 1 via the power conversion device 80. The power connector 10 includes a positive electrode terminal 11 and a negative electrode terminal 12, which will be described later with reference to FIG. 2.

[0020] The power connector 10 may be fitted into a hole (not shown) in the side wall portion 244 of the inverter case portion 24. In this case, the power connector 10 may be attached to the side wall portion 244 in a manner of being inserted in the Y direction.

[0021] The power conversion device 80 is electrically connected between the rotating electric machine 1 and the power source BA. The power conversion device 80 may be in the form of a module integrating various components. The power conversion device 80 may include a plurality of switching elements (power semiconductor elements) constituting the inverter circuit 82, a control board on which a control device for controlling the inverter circuit 82 (see FIG. 2), a smoothing capacitor 84 (see FIG. 2), and the like.

[0022] The power converter 80 may be fixed to the partition wall 29 that forms the bottom of the inverter case 24, as shown in Figure 1. The partition wall 29 is a wall that separates the motor housing chamber S1 and the inverter housing chamber S4. More specifically, the power converter 80 may be fixed to the partition wall 29 via a water channel forming member 294, which is a separate component from the partition wall 29. A water channel for cooling water may be formed in the water channel forming member 294. In a modified example, a water channel may be formed in the partition wall 29, and the power converter 80 may be cooled together with the rotating electric machine 1 by the partition wall 29. In this case, the power converter 80 may be directly fixed to the partition wall 29.

[0023] In this embodiment, the case 2 integrally forms a motor housing chamber S1 in which the rotating electric machine 1 is arranged and an inverter housing chamber S4 (second housing chamber) in which the power conversion device 80 is arranged, separated by a partition wall 29.

[0024] The rotating electric machine 1 and the power converter 80 are electrically connected via a wiring structure 9. The wiring structure 9 may include power lines (not shown) from the rotating electric machine 1 and busbars (not shown) for each phase.

[0025] Figure 2 shows an example of an electrical circuit 5 including a power converter 80. Electrical circuit 5 is an electrical circuit for driving a rotating electric machine 1.

[0026] The electrical circuit 5 includes a power supply BA, a Y capacitor 60, an inverter circuit 82, and a smoothing capacitor 84. The rotating electric machine 1 (Figure 1) is connected to the inverter circuit 82.

[0027] The smoothing capacitor 84 is connected between the positive terminal line of power supply BA and the negative terminal line of power supply BA.

[0028] The Y capacitor 60 is provided for noise suppression. The Y capacitor 60 includes a Gp terminal 626 that connects the positive line to ground, a Gn terminal 628 that connects the negative line to ground, capacitor C10, and capacitor C20. Capacitor C10 is connected between the positive line and the Gp terminal 626. Capacitor C10 is connected to the positive line via terminal P 61. Capacitor C20 is connected between the negative line and the Gn terminal 628. Capacitor C20 is connected to the negative line via terminal N 62.

[0029] Next, with reference to Figure 3 and subsequent figures, the mounting structure of the Y capacitor 60 in this embodiment will be described.

[0030] Figure 3 is a perspective view of the mounting structure of the Y capacitor 60, and is a perspective view showing the structure related to the Q1 portion in Figure 1. Figure 4 is an exploded perspective view of a part of Figure 3, and Figure 5 is an exploded perspective view of a further part of Figure 4. Figure 5A is an exploded perspective view showing three types of terminals (P terminal 61, N terminal 62, and ground terminal 63). Figure 6 is an explanatory diagram of a comparative example. Figure 7 is a front view of the mounting structure of the Y capacitor 60 viewed in the Y direction, and Figure 8 is a plan view of the mounting structure of the Y capacitor 60 viewed in the Z direction.

[0031] The Y capacitor 60 is electrically connected to the power supply BA via the power connector 10. As described above, the power connector 10 includes a positive terminal 11 and a negative terminal 12. The power connector 10 has a mounting portion 14 that extends in the XZ plane, and the mounting portion 14 abuts against the side wall portion 244 (not shown in Figure 3, see Figure 1) of the inverter case portion 24 in the Y direction. At this time, the positive terminal 11 and the negative terminal 12 extend into the interior of the inverter case portion 24 (i.e., the inverter housing chamber S4).

[0032] The terminal configuration of the Y capacitor 60 includes the P terminal 61 described above, the N terminal 62 described above, and the ground terminals 63 that form the two Gp terminals 626 and Gn terminals 628 described above.

[0033] The P terminal 61 electrically connects the capacitor C10 to the positive terminal side of the power supply BA. In this embodiment, one end 610 (see Figures 4 and 5A, etc.) of the P terminal 61 is joined to the substrate 66, and the other end is joined (fastened) to the positive terminal 11 of the power connector 10. The capacitor C10 has a positive terminal 71 and a ground terminal 73 that are joined to the substrate 66 (see Figure 5). In this case, the positive terminal 71 of the capacitor C10 is electrically connected to one end 610 of the P terminal 61 via the substrate 66. The substrate 66 extends in a plane parallel to the side wall 244 (i.e., in the XZ plane) and overlaps the capacitors C10 and C20 when viewed in the Y direction. That is, the substrate 66 is positioned between the capacitors C10 and C20 and the side wall 244 (see Figure 1) in the Y direction.

[0034] The N terminal 62 electrically connects the capacitor C20 to the negative terminal side of the power supply BA. In this embodiment, one end 620 (see Figures 4 and 5A, etc.) of the N terminal 62 is joined to the substrate 66, and the other end is joined (fastened) to the negative terminal 12 of the power connector 10. The capacitor C20 has a negative terminal 72 and a ground terminal 74 that are joined to the substrate 66 (see Figure 5). In this case, the negative terminal 72 of the capacitor C20 is electrically connected to one end 620 of the N terminal 62 via the substrate 66.

[0035] Each of the two ground terminals 63 electrically connects capacitors C10 and C20 to ground. In this embodiment, one end 630 (see Figures 4 and 5A, etc.) of each ground terminal 63 is joined to the substrate 66, and the other end is joined (fastened) to a member having ground potential (in this embodiment, a water channel forming member 294). The ground-side terminal 73 of capacitor C10 is electrically connected to one end 630 of one ground terminal 63 via the substrate 66, and the ground-side terminal 74 of capacitor C20 is electrically connected to one end 630 of the other ground terminal 63 via the substrate 66.

[0036] In this way, according to this embodiment, capacitors C10 and C20 can be electrically connected to the power supply BA and ground using the substrate 66 parallel to the side wall 244. This makes it possible to reduce the mounting space (mounting space in the Y direction) for the Y capacitor 60, as will be described later.

[0037] In this embodiment, as clearly shown in Figure 5A, the P terminal 61 has a fastening surface 611 whose normal direction is in the vertical direction (an example of the first direction). The fastening surface 611 forms the fastening surface (the surface having a hole for fastening the bolt BT1) with the positive terminal 11 of the power connector 10. That is, the P terminal 61 and the positive terminal 11 are overlapped in the Z direction and fastened together by the bolt BT1. In this case, the bolt BT1 is tightened toward the negative side along the Z direction.

[0038] Similarly, the N terminal 62 has a fastening surface 621 (a surface with a hole for fastening bolt BT2) whose normal direction is in the vertical direction (an example of the first direction). The fastening surface 621 forms the fastening surface with the negative terminal 12 of the power connector 10. That is, the N terminal 62 and the negative terminal 12 are superimposed in the Z direction and fastened together by bolt BT2. In this case, bolt BT2 is tightened toward the negative side along the Z direction. In this embodiment, the fastening surfaces 611 and 621 are surfaces in the same plane, but in a modified example, one may be offset vertically relative to the other.

[0039] Furthermore, as clearly shown in Figure 5A, the ground terminal 63 has a fastening surface 631 (a surface with a hole for fastening bolt BT3) whose normal direction is the Y direction (an example of a second direction). The fastening surface 631 forms a fastening surface with a member having ground potential. In this embodiment, as an example, the member having ground potential is the water channel forming member 294. The fastening surface on the water channel forming member 294 side is the side surface whose normal direction is the Y direction. The side surface of the water channel forming member 294, which is the fastening surface, faces the side wall portion 244 of the inverter case portion 24 to which the power connector 10 is attached. In this case, the ground terminal 63 and the water channel forming member 294 are overlapped in the Y direction and fastened with bolt BT3. In this case, bolt BT3 is tightened toward the positive side along the Y direction.

[0040] Incidentally, in the comparative example Y capacitor 60' schematically shown in Figure 6, for example, each terminal 61', 62', and 63' are fastening surfaces with the vertical direction as the normal direction, unlike in this embodiment. In this case, when viewed in the vertical direction, the fastening surfaces (especially the bolt holes) of each terminal 61', 62', and 63' need to be positioned so as not to overlap with each other, taking into consideration the workability when fastening bolts. Therefore, in such a comparative example, the mounting space for the Y capacitor 60' when viewed in the vertical direction tends to be relatively large. In other words, the mounting space for the Y capacitor 60' tends to be a factor that hinders the miniaturization of the power conversion device (size in the XY plane).

[0041] In contrast, according to this embodiment, as described above, the fastening surfaces 611 and 621 of the P terminal 61 and N terminal 62, respectively, and the fastening surface 631 of the ground terminal 63 have different normal directions. This makes it possible to reduce the mounting space required for the Y capacitor 60.

[0042] In this embodiment, the fastening surfaces 611 and 621 of the P terminal 61 and N terminal 62, respectively, and the ground terminal 63, or the bolt BT3 fastening the ground terminal 63, may be arranged in a positional relationship that overlaps when viewed in the vertical direction. For example, when viewed in the vertical direction, the fastening surface 611 (or the bolt BT1 fastened thereto) may overlap one of the bolts BT3 fastening the ground terminal 63, and the fastening surface 621 (or the bolt BT2 fastened thereto) may overlap the other of the bolts BT3 fastening the ground terminal 63. In this case, the mounting space for the Y capacitor 60 can be reduced even more effectively.

[0043] Furthermore, according to this embodiment, as described above, the mounting space for the Y capacitor 60 can be set adjacent to the side wall 244. That is, when viewed in the vertical direction, the mounting space for the Y capacitor 60 can be positioned adjacent to the side wall 244 and relatively far to the negative side in the Y direction. This makes it easy to secure mounting space for other components on the positive side in the Y direction from the Y capacitor 60 in the inverter housing chamber S4. Also, by consolidating the mounting space for other components to the negative side in the Y direction, the Y-direction size of the power converter 80 can be reduced. For example, as in this embodiment, when the Y capacitor 60 is positioned between the smoothing capacitor 84 and the side wall 244 in the Y direction, the Y-direction distance between the smoothing capacitor 84 and the side wall 244 can be minimized. As a result, the Y-direction size of the power converter 80 can be effectively reduced.

[0044] In this embodiment, the water channel forming member 294 preferably has a recess 2940 that is recessed on the side away from the side wall portion 244 when viewed in the vertical direction, as shown in Figure 8. In this case, the ground terminal 63 may be placed in the recess 2940, as shown in Figure 7. The entire substrate 66 and part of the bolt BT3 may also be placed in the recess 2940, as shown in Figure 7. This makes it possible to further move the mounting space for the Y capacitor 60 closer to the side wall portion 244 in the Y direction compared to when the recess 2940 is not formed. As a result, the Y-direction size of the power converter 80 can be effectively reduced.

[0045] In this embodiment, the Y capacitor 60 can be assembled to the inverter case 24 with the P terminal 61, N terminal 62, ground terminal 63, and circuit board 66 already assembled to the water channel forming member 294 along with capacitors C10 and C20 (i.e., the ground terminal 63 is fastened to the water channel forming member 294 by bolt BT3). In this case, the fastening of bolts BT1 and BT2 between the P terminal 61 and N terminal 62 and the positive terminal 11 and negative terminal 12 of the power connector 10 may be performed after the water channel forming member 294 (and consequently the Y capacitor 60) has been assembled to the inverter case 24. In this case, the assembly of the Y capacitor 60 can be easily completed by assembling the power connector 10 to the side wall 244 of the inverter case 24 and fastening bolts BT1 and BT2 to the P terminal 61 and N terminal 62 which overlap vertically and to the positive terminal 11 and negative terminal 12 of the power connector 10.

[0046] Although each embodiment has been described in detail above, the invention is not limited to any particular embodiment, and various modifications and changes are possible within the scope described in the claims. Furthermore, it is possible to combine all or more of the components of the embodiments described above.

[0047] For example, in the embodiment described above, the cylindrical capacitors C10 and C20 are arranged with their axial direction aligned with the Z direction, but this is not limited to this. For example, the cylindrical capacitors C10 and C20 may be arranged with their axial direction aligned with the X direction. In this case, the mounting space in the X direction may increase, but the mounting space in the Z direction can be reduced, thereby reducing the overall height of the power converter 80.

[0048] Furthermore, in the above-described embodiment, the P terminal 61 and N terminal 62 are not configured to be elastically deformable in the vertical direction, but the P terminal 61 and N terminal 62 may be configured to be elastically deformable in the vertical direction. For example, the P terminal 61 and N terminal 62 may have an elastically deformable part (not shown) that supports the fastening surfaces 611 and 621 so as to be displaceable in the vertical direction. In this case, even if a deviation from the design value (nominal value) occurs between the fastening surface 611 of the P terminal 61 and the fastening surface of the positive terminal 11 of the power connector 10 due to various tolerances such as assembly tolerances, the deviation can be absorbed by the elastic deformation of the elastic deformation part, thereby reducing the stress on the fastening part. Similarly, even if a deviation from the design value (nominal value) occurs between the fastening surface 621 of the N terminal 62 and the fastening surface of the negative terminal 12 of the power connector 10, the deviation can be absorbed by the elastic deformation of the elastic deformation part, thereby reducing the stress on the fastening part. The form of the elastic deformation part is arbitrary and may be in the form of a leaf spring.

[0049] Furthermore, in the embodiment described above, the power connector 10 is fitted to the side wall portion 244, but other types of terminal portions may be fitted to the side wall portion 244 instead of the power connector 10. [Explanation of symbols]

[0050] 1... Rotating electric machine, 2... Case, 244... Side wall section, 60... Y capacitor, 61... P terminal (first terminal), 62... N terminal (second terminal), 63... GN terminal (third terminal), 611, 621... Fastening surface (first fastening surface), 631... Fastening surface (second fastening surface), 80... Power converter, 84... Smoothing capacitor, 294... Water channel forming member (member having ground potential), 2940... Recess, 100... Vehicle drive unit, BT3... Bolt (fastener)

Claims

1. A power conversion device that supplies power to a rotating electric machine, A case for housing the aforementioned power converter, A Y capacitor housed in the aforementioned case and electrically connected between the power converter and the power supply, A smoothing capacitor housed in the aforementioned case and electrically connected between the Y capacitor and the power converter, The aforementioned Y capacitor has a first terminal that is electrically connected to the positive terminal side of the power supply, The Y capacitor is electrically connected to a second terminal on the negative side of the power supply, The aforementioned Y capacitor has a third terminal that is electrically connected to ground, The first terminal and the second terminal have a first fastening surface with the first direction as the normal direction, and a first fastening surface with the terminal from the power supply side. The third terminal has a second fastening surface with a member having a ground potential, and the second fastening surface has a second direction normal to a direction different from the first direction. The case has a side wall portion on which the positive terminal and negative terminal from the power supply are arranged. The Y capacitor is positioned between the side wall and the smoothing capacitor in the second direction. The first direction corresponds to the vertical direction of the side wall portion, The second direction corresponds to a direction perpendicular to the surface of the side wall portion, and is a vehicle drive device.

2. The vehicle drive device according to claim 1, wherein the first fastening surface of at least one of the first terminal and the second terminal overlaps with the third terminal or a fastener for fastening the third terminal when viewed in the first direction.

3. The member having the ground potential has a recess that, when viewed in the first direction, is recessed on the side away from the side wall in the second direction, The vehicle drive device according to claim 1, wherein at least a portion of the third terminal, or at least a portion of the fastener for fastening the third terminal, is arranged in the recess when viewed in the first direction.

Images