Drive unit

Abstract

To provide a drive unit that can suppress propagation of noise generated in a power control unit while preventing increase in the physical constitution.SOLUTION: A drive unit 70 comprises: a second electric motor MG2 as a rotary electric machine; a power control unit 54 for driving and controlling the second electric motor MG2; a case 18 for storing the power control unit 54; and a terminal block 80 fixed to the case 18, wherein (a) the terminal block 80 is provided with a plurality of bus bars 86 to receive outputs of the power control unit 54, (b) a split type ferrite core member 90 including an annular ferrite core 92 surrounding the bus bars 86 is provided in a circumferential direction centered about a direction of extension of the bus bars 86, and (c) the terminal block 80 and the ferrite core member 90 are co-tightened to a partition wall 18c of the case 18 by bolts 100 as fasteners.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a drive unit including a power control device for driving and controlling a rotating electric machine, a case for housing the power control device, and a terminal block fixed to the case.

Background Art

[0002] A drive unit including a power control device for driving and controlling a rotating electric machine, a case for housing the power control device, and a terminal block fixed to the case is known. For example, the one described in Patent Document 1 is such a drive unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the drive unit described in Patent Document 1, noise generated in the power control device, so-called EMC (electromagnetic compatibility) noise, is propagated as conductive noise to the stator of the rotating electric machine through a plurality of connection lines of the terminal block. Hereinafter, in this specification, EMC noise is simply referred to as "noise". The conductive noise propagated to the stator of the rotating electric machine is propagated to the drive shaft through the rotor, rotor shaft, bearings, case, etc. of the rotating electric machine. The conductive noise propagated to the drive shaft is radiated into the air as radiated noise. If the radiated noise is large, it may affect peripheral devices. Also, in suppressing the propagation of noise generated in the power control device, it is also desirable to suppress an increase in the size of the drive unit.

[0005] The present invention was made against the above circumstances, and its objective is to provide a drive unit that can suppress the propagation of noise generated by a power control device while suppressing an increase in body size. [Means for solving the problem]

[0006] The gist of the present invention is a rotating electric machine, a power control device for driving and controlling the rotating electric machine, and a case for housing the power control device. Having a plate-like portion A terminal block fixed to the aforementioned case, Ferrite core material, A drive unit comprising (a) the terminal block the plate-like portion for, Through hole and Multiple connecting lines to which the output of the power control device is supplied A cylindrical part through which it passes, (b) The ferrite core member is In the circumferential direction centered on the direction in which the plurality of connecting lines extend, the plurality of connecting lines are surrounded Split type Annular ferrite core The annular ferrite core is detachably held by a retaining member, and the retaining member is attached to the case by a mounting portion. Including, split type and (c) The terminal block and the ferrite core member , a common through hole in the plate-shaped part and through hole in the mounting part The case is fastened together with the fasteners. [Effects of the Invention]

[0007] According to the drive unit of the present invention, (a) the terminal block the plate-shaped portion for, Through hole and Multiple connecting lines to which the output of the power control device is supplied A cylindrical part through which it passes, (b) The ferrite core member is In the circumferential direction centered on the direction in which the plurality of connecting lines extend, the plurality of connecting lines are surrounded Split type Annular ferrite core The annular ferrite core is detachably held by a retaining member, and the retaining member is attached to the case by a mounting portion. Including, split type and (c) The terminal block and the ferrite core member , a common through hole in the plate-shaped part and through hole in the mounting partThe terminal block and ferrite core are fastened together to the case by fasteners. Because the ferrite core member is of the split type, the shape of the multiple connection wires is not easily restricted, and the ferrite core member can be easily attached and detached. For example, depending on the type of drive unit, it is easy to change to a ferrite core member with different impedance characteristics to suit the suppression of noise propagation generated by the power control device. Since the terminal block and ferrite core member are fixed to the case by fastening together, the increase in the size of the drive unit is suppressed compared to when the ferrite core member is fixed to the case separately from the terminal block. Therefore, it is possible to suppress the propagation of noise generated by the power control device while suppressing the increase in the size of the drive unit. [Brief explanation of the drawing]

[0008] [Figure 1] This diagram illustrates an example of the schematic configuration of a vehicle equipped with the drive unit according to Embodiment 1. [Figure 2] This diagram illustrates an example of the electrical configuration of a power control device. [Figure 3] This is a perspective view illustrating the state in which the terminal block and ferrite core member are fastened together with the case partition wall. [Figure 4] This diagram illustrates the configuration of a terminal block and a ferrite core member, and is a cross-sectional view perpendicular to the direction in which the extension portion of the busbar extends. [Figure 5] This diagram illustrates the configuration of the terminal block and ferrite core member, and is a cross-sectional view of the cutting line VV shown in Figure 4. [Modes for carrying out the invention]

[0009] The embodiments of the present invention will be described in detail below with reference to the drawings. Note that the drawings in each embodiment have been simplified or modified as appropriate, and the dimensional ratios and shapes of each part are not necessarily accurately depicted. [Examples]

[0010] Figure 1 is a diagram illustrating an example of the schematic configuration of a vehicle 10 equipped with the drive unit 70 according to Embodiment 1.

[0011] Vehicle 10 is a hybrid vehicle comprising an engine 12 that functions as a power source, and a first motor MG1 and a second motor MG2 that function as power sources. Vehicle 10 also comprises a pair of drive wheels 14 and a power transmission device 16. The engine 12 is a well-known internal combustion engine. The first motor MG1 and the second motor MG2 are, for example, rotating electric machines having motor and generator functions, and are so-called motor generators. The first motor MG1 and the second motor MG2 are power sources for the vehicle 10 to run, and are, for example, three-phase synchronous motors. The first motor MG1 comprises a stator MG1s and a rotor MG1r. The rotor shaft RSmg1 is integrally connected to the rotor MG1r. The second motor MG2 comprises a stator MG2s and a rotor MG2r. The rotor shaft RSmg2 is integrally connected to the rotor MG2r. The first motor MG1 and the second motor MG2 are housed in a non-rotatable case 18, which is a non-rotating member attached to the vehicle body. The first electric motor MG1 and the second electric motor MG2 each correspond to the "rotating electric machine" in this invention.

[0012] The power transmission device 16, in the power transmission path between the engine 12 and the pair of drive wheels 14, includes, in order from the engine 12 side, a crankshaft 12a, a damper 20, an input shaft 22, a transmission unit 24, a compound gear 26, a driven gear 28, a driven shaft 30, a final gear 32, a differential gear 34, etc., within the case 18 in the power transmission path between the second electric motor MG2 and the pair of drive wheels 14, includes, in order from the second electric motor MG2 side, a rotor connecting shaft 38, a reduction gear 36, a driven gear 28, a driven shaft 30, a final gear 32, a differential gear 34, etc., within the case 18 in the power transmission path between the second electric motor MG2 and the pair of drive wheels 14, in the order from the second electric motor MG2 side, a rotor connecting shaft 38, a reduction gear 36, a driven gear 28, a driven shaft 30, a final gear 32, a differential gear 34, etc., within the case 18 in the power transmission path between the second electric motor MG2 and the pair of drive wheels 14, within the case 18 in the order from the second electric motor MG2 side, a rotor connecting shaft 38, a reduction gear 36, a driven gear 28, a driven shaft 30, a final gear 32, a differential gear 34, etc., within the power transmission path between the engine 12 and the pair of drive wheels 14. Each of these components of the power transmission device 16 is made of, for example, steel. The case 18 is made of, for example, a casting of an aluminum alloy.

[0013] The differential mechanism 42 included in the speed change section 24 is configured by a known single pinion type planetary gear device. The speed change section 24 is a known electric speed change mechanism in which the differential state of the differential mechanism 42 is controlled by controlling the operating state of the first electric motor MG1. Note that the first electric motor MG1 can also function as a power source that outputs power to the pair of drive wheels 14 via the differential mechanism 42.

[0014] Each component included in the power transmission device 16, the first electric motor MG1, and the second electric motor MG2 is supported by the case 18 so as to be rotatable via bearings. For example, lubricating oil stored at the bottom of the case 18 (specifically, the bottom of the lower space L described later), for example, ATF (Automatic Transmission Fluid), is scraped up by the differential ring gear 34a or the like and used for lubricating the gears and bearings in the case 18. Also, the lubricating oil is scattered around by the rotation of the gears in the case 18.

[0015] FIG. 2 is a diagram for explaining an example of an electrical configuration of the power control device 54 and the like.

[0016] Vehicle 10 further includes a high-voltage battery 46, an auxiliary battery 48, and a power control device 54. The high-voltage battery 46 is a rechargeable secondary battery, such as a nickel-metal hydride secondary battery or a lithium-ion battery. The high-voltage battery 46 is connected to the power control device 54 via a third power line PL3, a terminal block 180, and a fourth power line PL4. The high-voltage battery 46 is a battery for driving the first motor MG1 and the second motor MG2. From the high-voltage battery 46, for example, stored power is supplied to the second motor MG2 via the power control device 54. The first motor MG1 and the second motor MG2 generate electricity using the power from the engine 12 and the driven force input from a pair of drive wheels 14, respectively, and this generated electricity is charged to the high-voltage battery 46 via the power control device 54. Details of the terminal block 180 will be explained in Embodiment 2 below. The auxiliary battery 48 is a rechargeable secondary battery, such as a lead-acid battery. The auxiliary battery 48 has a lower charging voltage than the high-voltage battery 46. The auxiliary battery 48 is charged by power generated by the alternator, which is rotationally driven by the engine 12, and by power supplied from the high-voltage battery 46 via the fourth power line PL4, terminal block 180, third power line PL3, and DC-DC converter 56.

[0017] The power control device 54 drives and controls the first motor MG1 and the second motor MG2, respectively. The power control device 54 comprises a DC-DC converter 56, a boost converter 60, an inverter 62, and a motor control device 58. The power control device 54 is a power control device that controls the power exchanged between the high-voltage battery 46 and the first motor MG1 and the second motor MG2, that is, the power exchanged by the first motor MG1 and the second motor MG2, respectively.

[0018] The DC-DC converter 56 is connected to the high-voltage battery 46. The DC-DC converter 56 functions as a charging device that steps down the voltage of the high-voltage battery 46 to a voltage equivalent to that of the auxiliary battery 48 and charges the auxiliary battery 48. The auxiliary battery 48 supplies power to operate the auxiliary equipment provided in the vehicle 10. The auxiliary battery 48 supplies power to operate, for example, the engine control device 52 and the electric motor control device 58.

[0019] The boost converter 60 includes reactors and switching elements (not shown). The boost converter 60 is a buck-boost circuit that has the function of boosting the voltage of the high-voltage battery 46 and supplying it to the inverter 62, and the function of stepping down the voltage converted to DC by the inverter 62 and supplying it to the high-voltage battery 46.

[0020] The inverter 62 includes an MG1 power module 64, an MG2 power module 66, and the like. The MG1 power module 64 and the MG2 power module 66 each include switching elements (not shown). The MG2 power module 66 is connected to the second motor MG2 via the first power line PL1, terminal block 80, and second power line PL2. The inverter 62 converts the DC current output from the boost converter 60 into AC current to drive the first motor MG1 and the second motor MG2. The inverter 62 converts the AC current generated by the first motor MG1 and the AC current generated by the second motor MG2 into DC current, respectively. The inverter 62 uses the power generated by the first motor MG1 to drive the second motor MG2, depending on the running conditions.

[0021] The electronic control unit 50 transmits and receives signals to and from the DC-DC converter 56, the motor control unit 58, and the engine control unit 52, for example, via a known CAN (Controller Area Network) communication line. The electronic control unit 50 controls the driving state of the vehicle 10 based on signals from, for example, sensors (not shown). The electronic control unit 50 reduces the voltage of the high-voltage battery 46 to the same voltage as the auxiliary battery 48 by, for example, controlling the DC-DC converter 56. In this embodiment, the electronic control unit 50 and the engine control unit 52 are each separate control units from the power control unit 54, particularly the motor control unit 58.

[0022] The motor control device 58 controls the first motor MG1 and the second motor MG2 based on the output request values ​​from the electronic control device 50. For example, the motor control device 58 controls the boost converter 60 and the inverter 62 to control the respective outputs of the first motor MG1 and the second motor MG2.

[0023] Returning to Figure 1, the transaxle 72 is a drive unit that includes a power transmission device 16 (speed transmission unit 24, compound gear 26, driven gear 28, driven shaft 30, final gear 32, etc.), a first electric motor MG1, and a second electric motor MG2. The drive unit 70 is a unit in which the transaxle 72 and the power control device 54 are housed in the same case 18 and integrated, i.e., a mechatronic integrated unit.

[0024] Case 18 is, for example, a case in which multiple members are integrally connected by fasteners such as bolts 74, 76, and 78. The interior of Case 18 is divided vertically by a partition wall 18c. Case 18 has an upper space U and a lower space L, which are divided vertically by the partition wall 18c. The side wall of Case 18 that partitions the upper space U is side wall 18a, and the side wall of Case 18 that partitions the lower space L is side wall 18b. The partition wall 18c is a common partition wall provided on the lower side that partitions the upper space U and the upper side that partitions the lower space L. Therefore, when the upper space U and the lower space L are separated in Case 18, at least one of the upper space U and the lower space L will always be exposed to the outside. "Same case" means a case in which, when the upper space U and the lower space L are separated in this way, at least one of them will be exposed to the outside.

[0025] Returning to Figure 2, in the mounted state in the vehicle 10, the power control device 54 is housed in the upper space U, and the transaxle 72 is housed in the lower space L. In the case 18, the transaxle 72 is installed in the lower space L before the opening on the side wall 18b opposite to the engine 12 is closed. In the case 18, the power control device 54 is installed in the upper space U before the opening on the upper surface that partitions the upper space U is closed.

[0026] Figure 3 is a perspective view illustrating the state in which the terminal block 80 and the ferrite core member 90 are fastened together to the partition wall 18c. The upper part of Figure 3 shows the state in which the terminal block 80 and the ferrite core member 90 are fastened together to the partition wall 18c by a common bolt 100, while the lower part of Figure 3 shows the state before the terminal block 80 and the ferrite core member 90 are fastened together to the partition wall 18c. Figure 4 is a diagram illustrating the configuration of the terminal block 80 and the ferrite core member 90, and is a cross-sectional view perpendicular to the direction in which the extension portion 86e of the busbar 86, which will be described later, extends. Figure 5 is a diagram illustrating the configuration of the terminal block 80 and the ferrite core member 90, and is a cross-sectional view along the cutting line VV shown in Figure 4. Figure 4 is a cross-sectional view along the cutting line IV-IV shown in Figure 5. Note that in Figure 4, the components of the terminal block 80 other than the busbar 86 are not shown. Figures 4 and 5 illustrate the state before the terminal block 80 and the ferrite core member 90 are fastened together to the partition wall 18c.

[0027] Terminal block 80 is a terminal block provided between the MG2 power module 66 of the power control device 54 and the stator MG2s of the second motor MG2. Terminal block 80 is fixed to the partition wall 18c. Terminal block 80 is for connecting the first power line PL1 located inside the upper space U and the second power line PL2 located outside the upper space U. A terminal block with a similar configuration to terminal block 80 is also provided between the MG1 power module 64 of the power control device 54 and the stator MG1s of the first motor MG1. The configuration of terminal block 80 will be described below as a representative example. Terminal block 80 corresponds to "terminal block" in this invention. Partition wall 18c corresponds to "case" in this invention.

[0028] The partition wall 18c is provided with a through hole 18c1. The through hole 18c1 is a hole through which the cylindrical portion 84 of the terminal block 80, which will be described later, can be inserted. The upper part of the partition wall 18c is provided with a stepped portion 18c2 (see Figure 5) that surrounds the through hole 18c1. The stepped portion 18c2 is, for example, a part of the partition wall 18c that is thicker than its surroundings and protrudes upward, and its upper surface is flush with the surface. The partition wall 18c is provided with two fastening holes 18c3 (see Figure 5).

[0029] The terminal block 80 comprises a plate-shaped portion 82 and a plurality (three in this embodiment) of cylindrical portions 84. The terminal block 80 is made of a metal that is relatively hard and resistant to elastic deformation. The lower surface of the plate-shaped portion 82 is plate-shaped and can cover the upper surface of the stepped portion 18c2. The cylindrical portions 84 are cylindrical and extend in the same direction from the lower surface of the plate-shaped portion 82. The plate-shaped portion 82 is provided with holes that are connected to the hollow portions of the three cylindrical portions 84. The through-hole 84h is a through-hole that connects a hole provided in the plate-shaped portion 82 to the hollow portion of the cylindrical portion 84.

[0030] The terminal block 80 includes busbars 86, each inserted through a through-hole 84h. The busbars 86 extend both inside and outside the upper space U. The busbars 86 are, for example, conductive metal plates. When the power control device 54 drives the second motor MG2, the output of the power control device 54 is supplied to the busbars 86. The busbars 86 are connecting lines through which three-phase alternating currents of the U-phase, V-phase, and W-phase flow at the terminal block 80.

[0031] Each bus bar 86 has a portion that extends in the same direction after passing through the through hole 84h into the interior of the upper space U. In the bus bar 86, this portion extending in the same direction is the extended portion 86e. In this embodiment, the "circumferential direction centered on the extended portions 86e of the three bus bars 86" will be simply referred to as the "circumferential direction". Each bus bar 86 has a first connecting portion 86a at one end in its longitudinal direction and a second connecting portion 86b at the other end in its longitudinal direction. The first connecting portion 86a allows the first power line PL1 (see Figure 2) to be connected at the end of the bus bar 86 that is on the interior side of the upper space U. In this embodiment, the first connecting portion 86a is the tip portion where the thickness direction of the bus bar 86 is bent at 90° in the portion that extends in the interior of the upper space U after passing through the through hole 84h. The first connection portion 86a is provided with a hole so that a crimp terminal attached to the end of, for example, the first power line PL1 can be electrically connected with a bolt (not shown). The second connection portion 86b is the end of the busbar 86 that is on the outside of the upper space U, i.e., on the inside of the lower space L, to which the second power line PL2 (see Figure 2) can be connected. In this embodiment, the second connection portion 86b is the end of the portion of the busbar 86 that extends downward through the through hole 84h. The second connection portion 86b is provided with a hole so that a crimp terminal attached to the end of, for example, the second power line PL2 can be electrically connected with a bolt (not shown). Note that the busbar 86 corresponds to the "connecting line" in this invention.

[0032] Between the inner circumferential surface of the cylindrical portion 84 and the outer circumferential surface of the busbar 86 through which the through hole 84h is inserted, O-rings made of rubber, for example (not shown), are fitted. This seals the lower space L in an oil-tight manner.

[0033] The plate-like portion 82 is provided with through holes 82h (see Figure 5) corresponding to the positions of fastening holes 18c3 provided in the partition wall 18c.

[0034] The ferrite core member 90 comprises an annular ferrite core 92, a retaining member 94, and a mounting portion 96.

[0035] The annular ferrite core 92 is an annular ferrite core. A ferrite core is a magnetic material made of ferrite, such as a well-known one made of Ni-Zn. The annular ferrite core 92 comprises a first core portion 92a and a second core portion 92b. The shapes of the first core portion 92a and the second core portion 92b are, respectively, the shapes of one and the other of a halved annular ferrite core, and are, for example, arc shapes formed by bending a plate-like body in the thickness direction.

[0036] The retaining member 94 has a first retaining portion 94a that holds the first core portion 92a and a second retaining portion 94b that holds the second core portion 92b. The retaining member 94 (first retaining portion 94a and second retaining portion 94b) is made of, for example, synthetic resin.

[0037] The first retaining portion 94a and the second retaining portion 94b are each arc-shaped plate-like bodies formed by bending a plate-like body in the thickness direction. Each of the first retaining portion 94a and the second retaining portion 94b is provided with a groove extending in the circumferential direction on its inner circumference. The groove provided in the first retaining portion 94a is shaped so that the first core portion 92a can be fitted into it. The groove provided in the second retaining portion 94b is shaped so that the second core portion 92b can be fitted into it. Preferably, the groove in the first retaining portion 94a is shaped so that the first core portion 92a can be fitted into it and removed. The groove in the second retaining portion 94b is shaped so that the second core portion 92b can be fitted into it and removed.

[0038] The first retaining portion 94a and the second retaining portion 94b are provided with a pair of first locking portions 94c and a pair of second locking portions 94d so that they can lock together. For example, one of the pair of first locking portions 94c is provided at one circumferential end of the first retaining portion 94a, and one of the pair of second locking portions 94d is provided at the other circumferential end of the first retaining portion 94a. For example, the other of the pair of first locking portions 94c is provided at one circumferential end of the second retaining portion 94b, and the other of the pair of second locking portions 94d is provided at the other circumferential end of the second retaining portion 94b.

[0039] The mounting portion 96 is made of synthetic resin, for example, and is integrally molded with the first retaining portion 94a. The mounting portion 96 consists of two plate-like parts that protrude from the partition wall 18c side of the first retaining portion 94a in the direction opposite to that of the second retaining portion 94b. The mounting portion 96 is provided with through holes 96h (see Figure 5) corresponding to the positions of the through holes 82h in the plate-like portion 82.

[0040] The ferrite core member 90 is attached to the three busbars 86 by following the procedure below. First, the first core portion 92a is fitted into the groove on the inner circumference of the first retaining portion 94a, and the second core portion 92b is fitted into the groove on the inner circumference of the second retaining portion 94b. A strip of rubber 98 is wrapped around the extended portions 86e of the three busbars 86. The rubber 98 is insulating. Next, with the rubber 98 wrapped around the three busbars 86 in between, the first retaining portion 94a and the second retaining portion 94b are pushed against each other in the direction of the white arrow D shown in Figures 4 and 5. As a result, the pair of first locking portions 94c are locked together, and the pair of second locking portions 94d are locked together, fixing the first holding portion 94a and the second holding portion 94b so that they cannot move relative to each other, and fixing the first core portion 92a and the second core portion 92b in an annular shape so as to surround the extended portion 86e of the three busbars 86. Rubber 98 is positioned between the three busbars 86 and the first core portion 92a, and between the three busbars 86 and the second core portion 92b. "Locking" means being connected or fastened. Thus, the ferrite core member 90 is a divisible type in which the annular ferrite core 92 can be divided. "Divisible type" means that the annular ferrite core has a structure that can be divided and combined to attach to multiple busbars in a detachable manner. The rubber 98 corresponds to the "elastic member" in this invention.

[0041] When the first retaining portion 94a and the second retaining portion 94b are fixed so as not to move relative to each other, and the first core portion 92a and the second core portion 92b are fixed in an annular shape, the first retaining portion 94a has a pressing portion 94p1 that presses the first core portion 92a against the second core portion 92b, and the second retaining portion 94b has a pressing portion 94p2 that presses the second core portion 92b against the first core portion 92a. For example, the pressing portions 94p1 and 94p2 utilize flexibility. The pressing portion 94p1 includes a projection that protrudes inward from the bottom surface of the groove on the inner circumference of the first retaining portion 94a, and the pressing portion 94p2 includes a projection that protrudes inward from the bottom surface of the groove on the inner circumference of the second retaining portion 94b.

[0042] The terminal block 80 and the ferrite core member 90 are fastened together to the stepped portion 18c2. Specifically, the plate-shaped portion 82 is positioned to cover the stepped portion 18c2, and the mounting portion 96 of the ferrite core member 90 is positioned to cover the plate-shaped portion 82. Then, bolts 100, which are inserted through the through holes 82h and 96h, are screwed into the fastening holes 18c3. "Screwing together" means connecting the female threads by twisting and rotating the male threads relative to each other. In this way, the terminal block 80 and the ferrite core member 90 are fastened together to the partition wall 18c by bolts 100. Note that the bolts 100 correspond to the "fasteners" in this invention. In this way, the terminal block 80 is fixed together with the ferrite core member 90 to the inside of the upper space U in the partition wall 18c.

[0043] When the annular ferrite core 92 is fixed around the three busbars 86, the annular ferrite core 92 acts as if a coil were inserted around each of the busbars 86, suppressing the propagation of high-frequency noise components through the busbars 86. In other words, the annular ferrite core 92 functions as a noise filter. The noise filtering function of the annular ferrite core 92 varies depending on the material and shape of the annular ferrite core 92. For example, the impedance characteristics of the annular ferrite core 92 can be changed by changing the cross-sectional area and average magnetic path length of the annular ferrite core 92.

[0044] Incidentally, in the power control device 54, if the switching elements of, for example, the boost converter 60 or inverter 62 are switched at high speed, high-frequency noise is generated. This noise attempts to propagate as common-mode noise from the first power line PL1 through the busbar 86 to the second power line PL2. In this embodiment, since the ferrite core members 90 are provided so as to surround the three busbars 86, the propagation of noise generated in the power control device 54 to the stator MG2s of the second motor MG2 through the busbars 86 is suppressed.

[0045] For example, unlike in this embodiment, if the ferrite core member 90 is not provided, the noise generated by the power control device 54 is sequentially propagated via the busbar 86 to the stator MG2s (including the stator coil) of the second motor MG2, the rotor MG2r of the second motor MG2, and the rotor shaft RSmg2. The noise propagated to the rotor shaft RSmg2 is propagated to the pair of drive shafts 40 via the bearing and case 18, or to the pair of drive shafts 40 via the power transmission path between the second motor MG2 and the pair of drive wheels 14. The noise propagated to the pair of drive shafts 40 is radiated into the air as radiated noise. Since the pair of drive shafts 40 are rod-shaped, they are more likely to radiate noise than the box-shaped case 18.

[0046] According to this embodiment, (a) the terminal block 80 is provided with three busbars 86 to which the output of the power control device 54 is supplied, (b) a segmented ferrite core member 90 is provided, which includes an annular ferrite core 92 surrounding the three busbars 86 in the circumferential direction, and (c) the terminal block 80 and the ferrite core member 90 are fastened together to the partition wall 18c with bolts 100. Because the ferrite core member 90 is segmented, the shape of the busbars 86 is not easily restricted and the ferrite core member 90 can be easily attached and detached. For example, depending on the type of drive unit 70, it is easy to change to a ferrite core member 90 with different impedance characteristics to be suitable for suppressing the propagation of noise generated by the power control device 54. Because the terminal block 80 and the ferrite core member 90 are fixed to the partition wall 18c by fastening together, the increase in the size of the drive unit 70 is suppressed compared to the case where the ferrite core member 90 is fixed to the partition wall 18c separately from the terminal block 80. Therefore, it is possible to suppress the propagation of noise generated in the power control device 54 while suppressing an increase in the size of the drive unit 70.

[0047] According to this embodiment, (a) the ferrite core member 90 has a first core portion 92a and a second core portion 92b obtained by dividing an annular ferrite core 92, a first holding portion 94a that holds the first core portion 92a, and a second holding portion 94b that holds the second core portion 92b, (b) the first holding portion 94a and the second holding portion 94b are locked together so that the first core portion 92a and the second core portion 92b become annular, and (c) the first holding portion 94a has a pressing portion 94p1 that presses the first core portion 92a against the second core portion 92b, and the second holding portion 94b has a pressing portion 94p2 that presses the second core portion 92b against the first core portion 92a. In this way, one of the first core portion 92a and the second core portion 92b is pressed against the other by the pressing portions 94p1 and 94p2. As a result, the gap between the first core section 92a and the second core section 92b is narrowed, which increases the impedance of the annular ferrite core 92 to high-frequency noise components, making it easier to suppress the propagation of noise generated in the power control device 54 to the second motor MG2.

[0048] In this embodiment, insulating rubber 98 is placed between the three busbars 86 and the first core portion 92a, and between the three busbars 86 and the second core portion 92b. When rubber 98 is placed, compared to when rubber 98 is not placed, the annular ferrite core 92 is suppressed from being biased to one side relative to the center of the stretched portion 86e in the thickness direction of the stretched portion 86e of the busbar 86. In other words, it becomes easier to assemble the gap between the stretched portion 86e and the annular ferrite core 92 to a predetermined amount. As a result, the impedance characteristics of the annular ferrite core 92 with respect to high-frequency component noise are stabilized, and the propagation of noise generated by the power control device 54 to the second motor MG2 is stably suppressed. [Examples]

[0049] The drive unit 70 according to Embodiment 2 is mounted on a vehicle 10 having the same configuration as Embodiment 1 described above. In this embodiment, the difference is that the "terminal block 80" and "ferrite core member 90" in Embodiment 1 are replaced with "terminal block 180" and "ferrite core member 190". Therefore, in this embodiment, the explanation will focus on the parts that differ from Embodiment 1, and parts that are substantially common will be given the same reference numerals and their explanations will be omitted as appropriate.

[0050] Terminal block 180 has substantially the same configuration as terminal block 80, but is fixed in a different position. Terminal block 180 is a terminal block installed between the boost converter 60 of the power control device 54 and the high-voltage battery 46. Terminal block 180 is fixed to the side wall 18a. Terminal block 180 is for connecting the third power line PL3 located inside the upper space U and the fourth power line PL4 located outside the upper space U. Terminal block 180 corresponds to the "terminal block" in this invention. The side wall 18a corresponds to the "case" in this invention.

[0051] The cylindrical portion of the terminal block 180 is inserted through a through hole 18a1 (see Figure 2) provided in the side wall 18a. The terminal block 180 includes busbars 186 that are inserted through the hollow portion of its cylindrical section. The busbars 186 extend to the inside and outside of the upper space U. For example, when the power generated by the second motor MG2 charges the high-voltage battery 46 via the power control device 54, the output of the power control device 54 is supplied to the busbars 186. The busbars 186 are connecting lines through which DC current flows at the terminal block 180. In this embodiment, however, strict sealing between the inside and outside of the upper space U is not required, as in the previously described Embodiment 1.

[0052] Each busbar 186 has portions that extend in the same direction, passing through the hollow portion of the cylindrical part of the terminal block 180 and extending into the interior of the upper space U. In the busbar 186, these portions extending in the same direction are called extended portions 186e. In this embodiment, the "circumferential direction centered on the extended portions 186e of the two busbars 186" will be simply referred to as the "circumferential direction." Each busbar 186 has a first connection portion 186a at one end in its longitudinal direction and a second connection portion 186b at the other end in its longitudinal direction. Note that the busbar 186 corresponds to the "connecting wire" in this invention.

[0053] The ferrite core member 190 has the same configuration as the ferrite core member 90, so its description is omitted. The terminal block 180 and the ferrite core member 190 are fixed to the side wall 18a by fastening them together with a common bolt 200 (see Figure 2). The bolt 200 corresponds to the "fastener" in this invention.

[0054] According to this embodiment, the same configuration as in Embodiment 1 described above provides the same effects as in Embodiment 1. For example, unlike this embodiment, if the ferrite core member 190 is not provided, noise generated by the power control device 54 is propagated to the fourth power line PL4 via the busbar 186. The noise propagated to the fourth power line PL4 is radiated into the air as radiated noise. Since the terminal block 180 and the ferrite core member 190 are fixed to the side wall 18a by fastening together, it is possible to suppress the propagation of noise generated by the power control device 54 while suppressing an increase in the size of the drive unit 70.

[0055] The above-described examples are embodiments of the present invention, and the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art, without departing from its spirit.

[0056] In the aforementioned embodiments 1 and 2, the ferrite core members 90 and 190 were configured such that the retaining member 94 had a divisible first retaining portion 94a and a second retaining portion 94b, but the present invention is not limited to this configuration. For example, the retaining member 94 in embodiments 1 and 2 may be provided with a hinge instead of the pair of second locking portions 94d, that is, the first retaining portion 94a and the second retaining portion 94b may be connected by a hinge.

[0057] In the aforementioned embodiments 1 and 2, the first holding portion 94a had a pressing portion 94p1 and the second holding portion 94b had a pressing portion 94p2, but the present invention is not limited to this embodiment. For example, the first holding portion 94a may not have a pressing portion 94p1 and the second holding portion 94b may not have a pressing portion 94p2. Preferably, at least one of the first holding portion 94a and the second holding portion 94b may have a pressing portion that presses one of the first core portion 92a and the second core portion 92b toward the other.

[0058] In the aforementioned embodiments 1 and 2, rubber 98 was arranged between the three busbars 86 and the annular ferrite core 92 of the ferrite core member 90, and between the two busbars 186 and the annular ferrite core 92 of the ferrite core member 190, respectively. However, the present invention is not limited to this embodiment. For example, there may be an embodiment in which rubber 98 is not arranged between the three busbars 86 and the annular ferrite core 92, that is, an embodiment in which there is a gap between the three busbars 86 and the annular ferrite core 92.

[0059] In the aforementioned embodiment 2, the terminal block 180 was provided between the boost converter 60 and the high-voltage battery 46, but it is not limited to this configuration and may be provided, for example, between the DC-DC converter 56 and the auxiliary battery 48.

[0060] In the aforementioned embodiments 1 and 2, the drive unit 70 was an integrated electromechanical unit in which the transaxle 72 and the power control device 54 were housed in the same case 18. However, the present invention is not limited to this. For example, it can also be applied to configurations in which the transaxle 72 and the power control device 54 are housed in separate cases. In this configuration, the member that partitions the space housing the power control device 54 corresponds to the "case" in the present invention.

[0061] In the aforementioned embodiments 1 and 2, the terminal blocks 80 and 180 were fixed to the inside of the upper space U in the partition wall 18c and side wall 18a by fastening them together with the ferrite core members 90 and 190, respectively. However, the present invention is not limited to this embodiment. For example, the terminal blocks 80 and 180 may be fixed to the outside of the upper space U in the partition wall 18c and side wall 18a by fastening them together with the ferrite core members 90 and 190.

[0062] In the aforementioned embodiments 1 and 2, the vehicle 10 was a hybrid vehicle equipped with an engine 12, a first electric motor MG1, and a second electric motor MG2 as power sources, but the present invention is not limited to this. For example, the present invention is also applicable to vehicles that do not have an engine 12 as a power source and only have electric motors, i.e., electric vehicles.

[0063] In the aforementioned embodiments 1 and 2, the second motor MG2, which corresponds to the "rotating electric machine" of the present invention, was a three-phase synchronous motor. However, the number of phases of the rotating electric machine is not limited to three phases, nor is it limited to a synchronous motor. Furthermore, for example, the second motor MG2 may be a rotating electric machine having only one of the functions of a motor or a generator.

[0064] In the aforementioned embodiments 1 and 2, the transaxle 72 included two electric motors, a first electric motor MG1 and a second electric motor MG2, but the present invention is not limited thereto. The transaxle 72 may include one electric motor or three or more. For example, an electric vehicle may not have a first electric motor MG1 as a power source, but may have only a second electric motor MG2. [Explanation of symbols]

[0065] 18a: Side wall (case), 18c: Partition wall (case), 54: Power control device, 70: Drive unit, 80: Terminal block (terminal block), 86: Busbar (connecting wire), 90: Ferrite core member, 92: Annular ferrite core, 92a: First core section, 92b: Second core section, 94a: First holding section, 94b: Second holding section, 94p1: Pressing section, 94p2: Pressing section, 98: Rubber (elastic member), 100: Bolt (fastener), 180: Terminal block (terminal block), 186: Busbar (connecting wire), 200: Bolt (fastener), MG1: First motor (rotating electric machine), MG2: Second motor (rotating electric machine)

Claims

1. A drive unit comprising a rotating electric machine, a power control device for driving and controlling the rotating electric machine, a case for housing the power control device, a terminal block having a plate-shaped portion and fixed to the case, and a ferrite core member, The plate-shaped portion of the terminal block is provided with a through hole and a cylindrical portion through which a plurality of connecting wires to which the output of the power control device is supplied are passed. The ferrite core member is of a split type and includes, in a circumferential direction centered on the direction in which the plurality of connecting wires extend, a split annular ferrite core surrounding the plurality of connecting wires, a holding member for detachably holding the annular ferrite core, and a mounting portion for attaching the holding member to the case. The terminal block and the ferrite core member are fastened together to the case by a common fastener that passes through the through-holes in the plate-shaped portion and the through-holes in the mounting portion. A drive unit characterized by the following features.

2. The ferrite core member comprises a first core portion and a second core portion obtained by dividing the annular ferrite core, a first retaining portion for holding the first core portion, and a second retaining portion for holding the second core portion. The first retaining portion and the second retaining portion are locked together so that the first core portion and the second core portion become annular. At least one of the first retaining portion and the second retaining portion has a pressing portion that presses one of the first core portion and the second core portion toward the other. The drive unit according to feature 1.

3. An insulating elastic member is disposed between the plurality of connecting wires and the first core portion, and between the plurality of connecting wires and the second core portion, respectively. The drive unit according to feature 2.

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