JP5602786B2 - Rotating electric machine - Google Patents

Description

  The present invention relates to a rotating electrical machine, and more particularly, to a rotating electrical machine equipped with a control device that controls the rotating electrical machine itself.

  In recent years, there has been an increasing demand for improvement in fuel consumption of transportation equipment against the background of global warming. As a result, there is an urgent need to reduce the size and weight of field winding type rotating electrical machines that supply electric power consumed by vehicle electrical components and charge the vehicle battery. However, in recent years, the number of electrical components and the resulting power consumption are increasing, and vehicular rotating electrical machines are required to have a larger power generation amount and higher power generation performance. Therefore, in order to meet these demands, rotation for vehicles such as an alternator equipped with a low-loss diode and a motor generator equipped with a power circuit unit as a power conversion device composed of power semiconductor elements such as MOS-FETs. Electric is being developed.

  The amount of heat generated by a vehicular rotating electrical machine is largely occupied by the copper loss of the stator winding and the rotor winding through which a large amount of current flows, and the iron loss generated during power generation. At this time, the power circuit unit as a power conversion device such as a rectifier and an inverter unit integrally provided in the vehicular rotating electrical machine is configured to transfer the heat caused by the copper loss and the iron loss to the stator, the rotor, and the power circuit. Heat is received through a housing that holds the part. These heats are discharged together with the heat generated in the power circuit unit from the heat sink provided in the power circuit unit.

  12A and 12B are explanatory views for explaining the fixing of the power circuit portion and the rear bracket in the conventional rotating electric machine, where FIG. 12A is a perspective view and FIG. 12B is a plan view. In FIG. 12, a heat sink 301 provided in the power circuit unit 30 is electrically connected to a metal terminal of a power semiconductor module (not shown) incorporating a power semiconductor element provided in the power circuit unit 30. Is insulated. The terminal 302 is electrically connected to a metal terminal of the power semiconductor module by welding or soldering. A terminal 302 electrically connected to the power semiconductor element is mechanically fixed and electrically connected to a power circuit portion fixing boss 71 provided on the rear bracket 7 of the rotating electrical machine by bolts or the like. Has been. The terminal 302 also has a function as a fixing portion that fixes the power circuit portion 30 to the rear bracket 7.

  By fixing the terminal 302 of the power circuit unit 30 to the rear bracket 7, the terminal on the lower arm side of the power conversion circuit configured by the power semiconductor element of the power circuit unit 30 is in direct contact with the rear bracket 7. Placed in. For this reason, the power circuit section 30 has several [W] to several tens [W] from the power circuit section fixing boss 71 that is a contact section between the rear bracket 7 of the rotating electrical machine and the terminal 302 to the inside of the power circuit section 30. Receive heat.

  The terminal 302 of the power circuit unit 30 that is in direct contact with the rear bracket 7 is connected to the upper surface of the power circuit unit 30 with a metal member, and the rear bracket 7 is made of aluminum having good heat conductivity. Most of the heat received from the heat 7 is transferred to the power circuit unit 30. As a result, heat is concentrated in the vicinity of the power circuit unit 30 due to heat generation due to power loss of the power semiconductor element and heat reception from the rear bracket 7.

  Therefore, it is necessary to install a heat sink 301 having high heat dissipation performance in the power circuit unit 30 in order to keep the temperature of the power semiconductor element within an allowable temperature. In order to satisfy this performance, the heat sink 301 is increased in size or the density of the heat dissipating fins, and there is a problem of a decrease in heat dissipation due to a decrease in the amount of cooling air due to an increase in the size of the power circuit unit 30 or an increase in air flow path resistance.

  As described above, the heat sink 301 provided in the power circuit unit 30 does not release only the heat generated in the power circuit unit 30 but discharges the heat generated in a part other than the power circuit unit 30 as the present situation. Yes. As a result, the heat sink 301 provided in the power circuit unit 30 of the vehicular rotating electrical machine dissipates heat generated from the power circuit unit 30 and heat received from the rear bracket 7 which is a housing, and the power semiconductor element in the power circuit unit 30 It is necessary to have a heat dissipation capability that can reduce the temperature below the allowable temperature. Due to such a problem, it is difficult to reduce the size of the heat sink 301, which is one of the adverse effects of downsizing the power circuit unit 30.

  In particular, a rotating electrical machine having a power circuit unit and a control circuit unit for controlling the power circuit unit, such as a motor generator, has a larger number of parts than an alternator and the like, and requires a reduction in size and weight of the rotating electrical machine. Is severe. In addition, when the size of the heat sink that can be set is limited, the temperature rise of the power semiconductor element mounted on the power circuit unit that receives a large amount of heat from the housing becomes large, causing a failure.

  For example, in the controller-integrated rotating electrical machine disclosed in Patent Document 1, the power circuit portion is connected to the rear bracket of the rotating electrical machine via a conductive stud, but the conductive stud is connected to the power circuit portion and the rear bracket. It is installed so as to provide a space between them. Accordingly, heat generated in the stator is prevented from flowing into the power circuit unit, and the cooling air can be easily ventilated, so that the temperature rise of the power circuit unit is reduced.

Japanese Patent No. 4351592

  However, in the conventional rotating electrical machine disclosed in Patent Document 1, it is necessary to provide a space between the power circuit unit and the housing of the rotating electrical machine, leading to an increase in product size (particularly an increase in axial length). . Moreover, the heat dissipation performance of the power circuit unit has a function of discharging not only the heat generation of the power circuit unit but also the heat generated by other members of the rotating electrical machine. For this reason, since the heat exhaustion part of the heat | fever which generate | occur | produced in the stator and rotor of members other than a power circuit part reduces, the temperature of members other than a power circuit part rises. As a result, it is necessary to take measures for heat dissipation in other heat generating portions, and there is a problem in that cost increases due to addition of members and product size increases.

  The present invention has been made to solve the above-mentioned problems in conventional rotating electrical machines, and reduces the amount of heat received by the power circuit section, thereby preventing the product size from being reduced and excessive temperature rise of the power circuit section. In addition, an object is to provide a rotating electrical machine having high productivity.

The rotating electrical machine according to the present invention is:
A rotor shaft rotatably supported by the housing;
A stator fixed to the housing and having an armature winding;
A rotor fixed to the rotor shaft and having a field core and a field winding;
A power circuit section composed of a MOS-FET acting as an inverter that performs power conversion between the armature winding and an external DC power source;
A wiring member provided in the power circuit section;
A heat sink for heat dissipation provided in the power circuit section;
With
A rotating electrical machine in which the power circuit portion is mounted on the housing by fixing the heat sink or the wiring member to the housing,
A heat dissipation plate inserted between the heat sink or the wiring member and the housing ,
Between the heat radiating plate and the heat sink or the wiring member, it is configured to have a thermal resistance larger than the thermal resistance between the radiating plate and the housing.
It is characterized by this.

  According to the rotating electrical machine of the present invention, since the heat sink or the heat sink plate inserted between the wiring member and the housing is provided, the amount of heat received by the power circuit unit is reduced, the product size is reduced, and the power circuit unit An excessively high temperature rise can be prevented and a rotating electrical machine having high productivity can be provided.

It is sectional drawing of the rotary electric machine by Embodiment 1 of this invention. It is a perspective view of the rear bracket in the rotary electric machine by Embodiment 1 of this invention, Comprising: It has shown in the state which mounted the power circuit part. It is a circuit diagram of the rotary electric machine by Embodiment 1 of this invention. It is explanatory drawing explaining the fixing | fixed part of a power circuit part and a rear bracket in the rotary electric machine by Embodiment 1 of this invention. It is explanatory drawing which shows the modification of the heat sink in the rotary electric machine by Embodiment 1 of this invention. It is explanatory drawing which shows another modification of the thermal radiation plate in the rotary electric machine by Embodiment 1 of this invention. It is explanatory drawing which shows another modification of the heat radiating plate in the rotary electric machine by Embodiment 1 of this invention. It is explanatory drawing which shows the heat radiating plate in the rotary electric machine by Embodiment 2 of this invention. It is explanatory drawing which shows the thermal radiation plate in the rotary electric machine by Embodiment 3 of this invention. It is explanatory drawing which shows the heat radiating plate in the rotary electric machine by Embodiment 4 of this invention. It is explanatory drawing explaining the modification of the heat sink in the rotary electric machine by Embodiment 4 of this invention, and fixation of a power circuit part. It is explanatory drawing explaining fixation with a power circuit part and a rear bracket in the conventional rotary electric machine.

Embodiment 1 FIG.
A rotating electrical machine according to Embodiment 1 of the present invention will be described below with reference to the drawings. 1 is a cross-sectional view of a rotating electrical machine according to Embodiment 1 of the present invention, and FIG. 2 is a perspective view of a rear bracket in the rotating electrical machine according to Embodiment 1 of the present invention, showing a state in which a power circuit portion is mounted. Show. The rotating electrical machine described in the first embodiment is an AC generator motor (motor generator) for a vehicle, but can be applied to an AC generator for a vehicle.

  1 and 2, the rotating electrical machine 100 includes a front bracket 6 as a housing and a rear bracket 7 as a housing, a bearing 19a fixed to the front bracket 6, a bearing 19b fixed to the rear bracket 7, The rotor shaft 1 is rotatably supported by the bearings 19a and 19b, the stator 5 sandwiched and fixed between the front bracket 6 and the rear bracket 7, and the armature winding 51 mounted on the stator 5. A rotor 10 fixed to the rotor shaft 1 and having a field core 2 and a field winding 3, and a pulley 20 fixed to the front end of the rotor shaft 1. The rotating electrical machine 100 is connected to an engine rotor shaft (not shown) via a belt (not shown) hung on the pulley 20.

  In the following description, the side where the front bracket 6 is installed is the front side of the rotating electrical machine 100 and the side where the rear bracket 7 is installed is the rotating electrical machine 100 when viewed from the axial center of the rotor shaft 1. This is called the rear side. Further, the front bracket 6 and the rear bracket 7 may be referred to as housings, respectively.

  Since the temperature of the rotor 10 and the stator 5 rises due to heat generated when the rotary electric machine 100 is driven, cooling fans 12 and 13 are provided on both end surfaces in the axial direction of the rotor 10. The front bracket 6 and the rear bracket 7 are manufactured by aluminum die casting from the viewpoint of weight reduction and productivity. A pair of slip rings 4 mounted on the rear side of the rotor shaft 1, a brush holder 80 attached to the rear bracket 7 so as to be positioned on the rear side outer periphery of the rotor shaft 1, and a pair of slip rings 4 A pair of brushes 8 disposed in the brush holder 80 is provided so as to be in contact with each other. A field current from a field circuit unit 31 to be described later is supplied to the field winding 3 via the pair of brushes 8 and the pair of slip rings 4.

  At the axially outer end of the rear bracket 7 of the rotating electrical machine 100, DC power from an in-vehicle battery (not shown) as an external DC power source is converted into AC power, or AC power from the armature winding 51 2 sets of power circuit units 30 having a power conversion circuit for converting DC power to DC power, a field circuit unit 31 for supplying a field current to the field winding 3 of the rotor 10, a power circuit unit 30 and a field circuit A control circuit unit 32 that controls the magnetic circuit unit 31 is mounted. The control device 200 includes two sets of a power circuit unit 30, a field circuit unit 31, a control circuit unit 32, and a control device cover 201 that covers them. The rotating electrical machine 100 is a so-called controller-integrated rotating electrical machine in which a control device 200 is mounted on the outer end of the rear bracket 7 in the axial direction.

  The armature winding 51 of the rotary electric machine 100 is configured by, for example, two sets of three-phase armature windings whose phases are shifted by 30 degrees, and these three-phase armature windings include a three-phase power conversion circuit. The two power circuit units 30 can be controlled independently of each other.

  FIG. 3 is a circuit diagram of the rotary electric machine according to Embodiment 1 of the present invention, and shows only one of the two sets of three-phase armature windings described above. In FIG. 3, the terminals of each phase of the Y-connected three-phase armature winding 51 are connected to the AC side terminals of the power conversion circuit configured by the six power semiconductor elements 30 a in the power circuit unit 30. Yes. The DC side terminal of the power conversion circuit in the power circuit unit 30 is connected to the in-vehicle battery B and the smoothing capacitor C. The field circuit unit 31 is connected to the in-vehicle battery B and the smoothing capacitor C through the two semiconductor elements 3a.

  When the rotary electric machine 100 is operated as an electric motor, the power semiconductor element 30a is switching-controlled by the control circuit unit 32 so that the power conversion circuit of the power circuit unit 30 operates as an inverter. As a result, the DC power from the in-vehicle battery B is converted into AC power by the power conversion circuit and supplied to the armature winding 51, and the armature winding 51 generates a rotating magnetic field to generate the field winding 3. The rotor 10 is rotated in cooperation with the direct current magnetic flux. At this time, the field current flowing in the field winding 3 is adjusted as necessary by the switching control of the semiconductor element 3 a by the control circuit unit 32.

On the other hand, when the rotating electrical machine 100 is operated as a generator, the power semiconductor element 30a is switching-controlled by the control circuit unit 32 so that the power conversion circuit of the power circuit unit 30 operates as a converter. As a result, the AC power generated in the armature winding 51 by the DC magnetic field generated by the field winding 3 of the rotating rotor 10 is converted into DC power by the power conversion circuit and supplied to the in-vehicle battery B. At this time, the field current flowing in the field winding 3 is adjusted as necessary by the switching control of the semiconductor element 3 a by the control circuit unit 32.

  Returning to FIG. 1 and FIG. 2, two sets of power circuit units 30 configured as described below include a plurality of the power semiconductor elements 30a described above and a heat sink 301 electrically insulated from the power semiconductor elements 30a. I have. Each power semiconductor element 30a is insert-molded in resin and electrically connected to each other. Further, the signal line connection terminal 304 of each power circuit unit 30 is connected to a control circuit provided on the control circuit board 321 in the control circuit unit 32 via a signal line connection member (not shown). Further, the AC side terminal 312 of each phase of the power circuit unit 30 is connected to the terminal of each phase of the armature winding 51. A control circuit provided on the control circuit board 321 of the control circuit unit 32 is connected to a lead wire (not shown) from the engine control unit ECU (not shown) via a lead wire connection unit 322.

  The control circuit unit 32 includes a control circuit board 321 and a resin case 323 for housing the control circuit board 321. The case 323 has a waterproof structure sealed with a waterproof cover (not shown) or the like in order to prevent salt mud water from entering the control circuit board 321 housed inside. The field circuit unit 31 can be mounted on the same substrate as the control circuit board 321 described above, but is configured separately from the control circuit board 321 in the first embodiment. The field circuit unit 31 includes a resin case 311, a semiconductor element 3 a housed in the case 311, and a heat sink 313 that closes an opening of the case 311. The heat sink 313 includes a plurality of cooling fins.

  The power circuit section 30 includes a resin case 303 and a terminal 302 electrically connected to a metal terminal of a power semiconductor module containing the power semiconductor element 30a housed in the case 303 by welding or soldering. And a heat sink 301 fixed to the case 303 by closing the opening of the case 303. The power semiconductor element 30 a is insert-molded in resin and mounted on the heat sink 301. The power semiconductor element 30a is electrically insulated from the heat sink 301. The heat sink 301 is provided for heat dissipation of the power semiconductor element 30a of the power circuit unit 30 because the power semiconductor element 30a provided in the power circuit unit 30 generates heat when energized, and is provided with a plurality of cooling fins. ing. The terminal 302 as a wiring member of the power circuit unit 30 has a function of a fixing unit for fixing the power circuit unit 30 to the rear bracket 7.

  A rotating electrical machine such as a motor generator includes a power circuit unit 30 that has both a rectification function of a generated current and a power conversion function such as an inverter. The power semiconductor element 30a constituting the power circuit unit 30 is constituted by a switchable power semiconductor element such as a MOS-FET and is formed by transfer molding together with a wiring member or a heat radiating member, or a resin case or enclosure. It is covered with and is made into a power module by potting with silicone gel. The power semiconductor element 30a formed into a power module is mounted on the heat sink 301 as described above.

  As shown in FIG. 2, the two sets of power circuit portions 30 are provided with power circuit portion fixing bosses 71 (FIG. 1) provided at the axially outer end of the rear bracket 7 of the rotating electrical machine 100 via the heat dissipation plate 305. (Not shown in FIG. 2). A metal heat radiating plate 305 inserted between the terminal 302 of the power circuit unit 30 and the rear bracket 7 is generated by a stator or the like of the rotating electrical machine 100 and flows into the terminal 302 of the power circuit unit 30 through the rear bracket 7. The heat is dissipated to the atmosphere, and the amount of heat received by the power circuit unit 30 from other members such as the rear bracket 7 is reduced, so that it is possible to supply a rotating electrical machine that is small and light and has high productivity.

  According to the rotating electrical machine according to the first embodiment of the present invention, the metal heat dissipation plate 305 is inserted between the terminal 302 of the power circuit unit 30 and the power circuit unit fixing boss 71 provided on the rear bracket 7. Since the heat generated in the stator 5 or the like and flowing into the power circuit unit 30 through the rear bracket 7 is radiated to the atmosphere, the amount of heat received by the power circuit unit 30 can be reduced. As a result, the heat dissipation performance required for the heat sink 301 mounted on the power circuit unit 30 can be lowered. As a result, the heat sink 301 of the power circuit unit 30 can be reduced in size, the number of radiating fins of the heat sink 301 can be reduced, and the fin pitch can be increased. As a result, the size of the rotating electrical machine can be reduced by reducing the size of the power circuit unit 30, and the heat dissipation of the rotating electrical machine can be improved by reducing the flow resistance of the cooling air.

  FIG. 4 is an explanatory view illustrating a fixing portion between the power circuit portion and the rear bracket in the rotary electric machine according to Embodiment 1 of the present invention. In FIG. 4, metal heat dissipation is provided between the power circuit portion 30 installed at the axially outer end of the rear bracket 7 of the rotating electrical machine 100 and the power circuit portion fixing boss 71 provided on the rear bracket 7. Plate 305 is inserted. As a result, heat generated in the stator 5 of the rotating electrical machine 100 and going to flow into the terminal 302 of the power circuit unit 30 through the rear bracket 7 is transmitted to the power circuit unit 30 through the heat radiating plate 305, The amount of heat received by the circuit unit 30 is reduced.

  The heat radiating plate 305 and the power circuit unit 30 are fixed to the power circuit unit fixing boss 71 of the rear bracket 7 with screws, bolts, rivets, caulking, and the like. Here, the heat dissipating plate 305 and the terminal 302 of the power circuit unit 30 are stacked on the rear bracket 7 in this order from the side close to the rear bracket 7 and fixed integrally.

  The surfaces where the heat radiating plate 305, the terminal 302, which is the fixing portion of the power circuit portion 30, and the power circuit portion fixing boss 71 of the rear bracket 7 are in contact with each other by any of the fixing methods described above. It is fixed in the state that was done. Part of the amount of heat that flows from the rear bracket 7 to the power circuit portion 30 flows into the heat radiating plate 305 fixed as described above. The heat dissipating plate 305 is installed such that the surface having the largest area in the vertical direction faces the cooling air flow direction generated by the rotation of the rotor 10 by the cooling fan 13 fixed to the rotor 10.

  As shown in FIG. 4, the heat radiating plate 305 is formed in a flat plate shape having a plane shape substantially the same as the plane shape of the terminal 302 of the power circuit unit 30, and fixes one power circuit unit 30. The rear bracket 7 is to be disposed across the pair of power circuit portion fixing bosses 71. The heat radiating plate 305 has a plurality of through holes 305 a formed at portions other than the fixing portion that contacts the pair of power circuit portion fixing bosses 71. As a result, the ambient air flows through the surface of the portion other than the fixed portion of the heat radiating plate 305 and is exposed to the ambient air, and a part of the heat received from the rear bracket 7 is easily released to the ambient air. Is done.

  5A and 5B are explanatory views showing a modification of the heat dissipation plate in the rotary electric machine according to Embodiment 1 of the present invention. FIG. 5A is a plan view showing a state in which the heat dissipation plate is attached to the rear bracket, and FIG. FIG. In FIG. 5, the heat dissipation plate 306 includes a plurality of through holes 306a. The opening surface of the through hole 306a formed in the heat radiating plate 306 is installed substantially perpendicular to the flow direction of the cooling air generated by the cooling fan 13 provided in the rotor 10 when the rotor 10 rotates. ing. Thereby, it is possible to minimize the increase in the flow resistance of the cooling air due to the installation of the heat radiating plate 306.

  Further, the heat radiating plate 306 includes fin portions 306b that are cut and raised at the same time as the through holes 306a are formed. Thereby, the heat radiating plate 306 can efficiently release the heat transmitted from the rear bracket 7 to the atmosphere by improving the heat radiating capability due to the increase in the heat radiating area to the atmosphere. Further, by providing the cut-and-raised fin portions 306b and the through holes 306a, it is possible to improve strength resistance against deformation when an external force is applied to the heat dissipation plate 306.

  FIG. 6 is an explanatory view showing another modification of the heat dissipation plate in the rotary electric machine according to Embodiment 1 of the present invention. In FIG. 6, the heat radiating plate 307 is provided with a concavo-convex portion 307 b on a line having a square cross-sectional shape as a low heat conduction region on the contact surface with the heat sink 301 on which the power circuit portion 30 is mounted or the terminal 302 of the power circuit portion 30. Is. Moreover, the heat radiating plate 307 is provided with the same through hole 307a as described above. According to the heat dissipation plate 307 configured as described above, the contact area between the heat dissipation plate 307, the heat sink 301 of the power circuit unit 30, and the terminal 302 can be limited.

  In this way, by providing the uneven portion 307b on the surface of the heat radiating plate 307, the thermal resistance of the contact portion between the heat radiating plate 307 and the power circuit portion 30 is increased, and the amount of heat flowing from the rear bracket 7 is reduced to the power circuit portion 30 side. It has the effect of making it difficult to communicate. The aforementioned concavo-convex portion 307b can be simultaneously formed when the heat radiating plate 307 is formed by sheet metal processing or casting, and an increase in manufacturing cost can be avoided.

  Note that the shape of the concavo-convex portion 307b in the heat radiating plate 307 does not have to be a square cross section, and may be a triangle or a polygon more than a square. The uneven portion 307b does not need to be in a line shape, and may be a lattice shape in which lines intersect or a complicated irregular shape.

  7A and 7B are explanatory views showing still another modified example of the heat dissipation plate in the rotary electric machine according to Embodiment 1 of the present invention. FIG. 7A is a perspective view of the heat dissipation plate, and FIG. It is explanatory drawing demonstrated. As shown in FIG. 7A, the heat radiating plate 308 has an annular shape as a low heat conduction region at the peripheral edge portion of the through hole provided at a position corresponding to the pair of power circuit portion fixing bosses 71 of the rear bracket 7. A pair of protrusions 308b are provided. Further, the heat radiating plate 308 is provided with the same through-hole 308a as described above.

  As shown in FIG. 7B, the heat dissipating plate 308 is placed on the pair of power circuit unit fixing bosses 71 of the rear bracket 7 so that the pair of annular protrusions 308b are on the power circuit unit 30 side. The terminal 302 of the power circuit unit 30 is placed on the axial end surfaces of the pair of annular protrusions 308b of the heat radiating plate 308, and is fixed to the axially outer end of the rear bracket 7 together with the heat radiating plate 308 by bolts or the like.

  The heat radiating plate 308 configured in this manner has an effect of increasing the thermal resistance of the contact portion between the heat radiating plate 308 and the power circuit unit 30 and making it difficult to transfer the amount of heat flowing from the rear bracket 7 to the power circuit unit 30 side. . The pair of circular annular protrusions 308b can be formed simultaneously when the heat dissipation plate 308 is formed by sheet metal processing or casting, and an increase in manufacturing cost can be avoided.

  The low heat conduction region of the heat radiating plate 308 is configured by a circular annular protrusion 308b. However, the heat transfer area is reduced from the contact portion between the heat radiating plate and the rear bracket 7 to the contact portion with the power circuit portion. Any other configuration may be used as long as it is a low heat conduction region. For example, the annular protrusion 308b of the heat radiating plate 308 does not need to be circular, and may be linear or dot-like.

  The heat radiating plate shown in FIGS. 6 and 7 is provided with the low heat conduction region as described above, so that the contact portion between the power circuit portion 30 and the heat radiating plate is fixed in a well-drained state. As a result, when the contact surface of the power circuit unit with the heat dissipation plate and the metal material exposed on the contact surface of the heat dissipation plate are a combination of different metals, the rotating electrical machine 100 is subjected to contact corrosion of different metals such as water. Even if a foreign object enters, the foreign object is immediately removed. As a result, it is possible to prevent the progress of different metal contact corrosion.

  The heat dissipation plates 305, 306, 307, and 308 described above efficiently diffuse the heat received from the power circuit portion fixing boss 71 of the rear bracket 7 into the heat dissipation plates 305, 306, 307, and 308, and have a wide area. It is preferable to use copper, aluminum, or a copper-based or aluminum-based alloy so that heat is exchanged with air. In FIG. 4, the heat radiating plate 305 has a thin flat plate shape, but may have a block shape having a thickness or a different thickness shape having a different thickness in the surface direction. By making the heat dissipating plates 305, 306, 307, and 308 in such a structure, it is possible to further reduce the amount of heat flowing into the power circuit unit 30 from other members through the rear bracket 7, and to reduce the temperature rise of the power circuit unit 30. As a result, the power circuit unit 30 can be downsized, the heat sink 301 for heat dissipation of the power circuit unit 30 can be downsized, and the chip size of the semiconductor module of the power circuit unit 30 can be reduced.

  As a result, the rotating electrical machine 100 can be reduced in size and weight and the material cost can be reduced. Further, the installation of the heat radiating plate 305 increases the heat radiating area occupying the entire rotating electric machine, and has the effect of reducing the temperature of members other than the power circuit unit 30 such as the stator 5. Furthermore, the radiation plate 305 is installed between the surface of the rear bracket 7 that faces the power circuit unit 30 and the power circuit unit 30, so that the radiant heat on the surface of the rear bracket 7 is transmitted to the power circuit unit 30. By avoiding this, the heat radiation plates 305, 306, 307, and 308 can exhaust heat to the outside atmosphere.

  In addition, since the heat dissipation performance of the heat sink 301 required by the power circuit unit 30 can be suppressed, the number of cooling fins necessary for the heat sink 301 can be reduced. As a result, the air path resistance when cooling air flows into the rotating electrical machine is reduced, and the amount of cooling air flowing into the rotating electrical machine can be increased. As a result, the heat generation of the stator 5 and the rotor 10 can be efficiently discharged to the outside, and the temperature rise suppression effect of the entire rotating electrical machine can be obtained.

  Furthermore, as a result of reducing the number of cooling fins of the heat sink 301, the fin pitch can be increased, and problems due to clogging of the cooling fins due to accumulation of dust, foreign matter, etc. from the outside can be avoided. Further, switching noise of the power circuit unit 30, switching noise of the control circuit unit 32, noise when a field current is applied to the brush 8 or the slip ring 4 that supplies a field current to the field winding 3 of the rotor 10. By fixing control ICs and sensors that are likely to malfunction due to noise to the surface opposite to the surface on which the power circuit unit 30 of the heat radiation plates 305, 306, 307, and 308 is fixed. , The adverse effects of noise can be reduced.

  Further, the control circuit cover 201 that covers the power circuit unit 30 and the like from the rear side is made of metal or conductive resin, and disposed so as to be in contact with the heat radiation plates 305, 306, 307, and 308. 30 and the members disposed in the vicinity thereof are covered with a member having a ground potential. Therefore, when the rotating electric machine 100 is mounted and fixed on a vehicle, there is an influence of noise caused by an external wiring member to be connected. Reduced.

  Further, the power circuit portion fixing boss 71 of the rear bracket 7 that fixes the heat radiation plates 305, 306, 307, and 308 and the power circuit portion 30, members such as bearings 19 a and 19 b that support the rotor shaft 1, and a rotation sensor. By installing in the vicinity, the temperature of the bearings 19a and 19b and the rotation sensor can be reduced and the temperature rise can be suppressed.

  In addition, although the heat dissipation plates 305, 306, 307, and 308 in the rotating electrical machine according to Embodiment 1 of the present invention have a flat plate shape in the drawing, they are not limited to the flat plate shape, but are bent shapes having steps. A curved shape has the same effect. Further, since the heat radiating plates 305, 306, 307, and 308 are installed perpendicular to the rotor shaft 1 of the rotating electrical machine 100, the cooling air to be exhausted by the cooling 13 fan is in or near the discharge path. Even when the interior of the rotating electrical machine 100 is recirculated by hitting the rear bracket 7 or the control device cover 201, the recirculated air is prevented from reaching the power circuit unit 30.

  The air that circulates inside the rotating electrical machine 100 receives heat from each member in the cooling air passage, and becomes higher than the ambient temperature. When the air that circulates inside reaches the power circuit unit 30, the power circuit unit 30 is simulated to be in the same state as that installed in a higher temperature atmosphere, when viewed from the ambient temperature outside the rotating electrical machine 100 The temperature rise of becomes large. Therefore, by introducing the air returning to the inside of the rotating electrical machine to the path through which the cooling 13 discharges the cooling air to the outside of the rotating electrical machine, it is possible to prevent the hot air from stagnating inside the rotating electrical machine 100, and Temperature rise can be prevented.

  Among in-vehicle rotating electrical machines, in-vehicle rotating electrical machines such as high-efficiency alternators and motor generators use low-loss diodes and MOS-FETs as power semiconductor elements. Since these elements generate a small amount of heat as compared with the diode mounted on the rectifier of the alternator, the temperature rise of the element due to self-heating is small when compared with the same amount of power generation. In such a case, the above-described heat radiation plates 305, 306, 307, and 308 are disposed between the power circuit unit 30 and the rear bracket 7 to reduce the amount of heat received by the power circuit unit 30, thereby reducing the temperature of the power semiconductor element. The rise can be greatly reduced.

Embodiment 2. FIG.
8A and 8B are explanatory views showing a heat radiating plate in a rotary electric machine according to Embodiment 2 of the present invention. FIG. 8A is a perspective view of the heat radiating plate, and FIG. . In FIG. 8, the heat radiating plates 309 installed between the two sets of power circuit portions 30 and the rear bracket 7 are integrally connected by a connecting portion 309c. Each of the connected heat radiating plates 309 includes a plurality of through holes 309a as in the case of the first embodiment. In this example, the heat radiating plate 309 is configured to be integrally connected by molding a single metal plate by press working. The integrally connected heat dissipating plate 309 is provided with a pair of annular protrusions 309b as thick portions for the same purpose as in FIG. The shape of the annular protrusion 309b is not necessarily circular, as in the case of the first embodiment.

  Since each heat radiating plate 309 is integrally connected, the surface area of the heat radiating plate 309 is increased, the heat radiating performance of the heat radiating plate 309 is improved, and each member mounted on the axially outer end of the rear bracket 7 The area acting as a radiant heat shield with the rear bracket 7 is increased, and the heat receiving of the power circuit 30 and other members mounted in the vicinity thereof can be reduced. Further, vibration resistance and structural strength of the heat radiating plate 309 and the power circuit unit 30 are also improved.

  In addition, each radiating plate 309 connected mutually can be connected by welding the separately formed radiating plate 309 by welding, instead of being integrally connected by molding from a single piece of metal. The plate 309 can be insert-molded collectively with resin as an insert material, formed into a connected shape by casting, or connected by screws, bolts, rivets, caulking, or the like. As shown in FIG. 8, by providing the heat radiating plate 309 with the annular protrusion 309b, a gap can be formed between the rear bracket 7 and the heat radiating plate 309, and the heat blocking performance to the power circuit unit 30 is further improved. be able to.

  Instead of the annular protrusion 309b, a vertical wall surface portion may be formed by pressing. At that time, by setting the vertical wall surface portion to the power circuit portion 30 side, the thermal resistance between the heat radiating plate 309 and the power circuit portion 30 can be increased, and the heat shielding property is improved. That is, since the thermal resistance is based on the thickness / cross-sectional area / thermal conductivity of the heat radiating plate 309, the thermal resistance between the heat radiating plate 309 and the power circuit unit 30 is increased, and the space between the rear bracket 7 and the heat radiating plate 309 is increased. Reducing the thermal resistance is effective for heat insulation, but the contact between the power circuit portion fixing boss 71 of the rear bracket 7 and the heat radiating plate 309 is a surface contact, and the surface contact portion and the power circuit If the protrusion is formed between the portion 30 by a process in which, for example, a plate having the same thickness as the heat radiating plate 30 is vertically raised, the cross-sectional area of the vertical wall surface portion can be reduced.

  In this case, the thickness, that is, the height of the vertical wall surface portion is made larger than at least the thickness of the plate material of the heat radiating plate 309, and the cross-sectional area of the vertical wall surface portion can be made as small as the plate thickness. Can be increased.

  Further, as another method of forming the thick portion in the heat radiating plate 309, a donut-shaped member different from the plane may be integrally fixed to the heat radiating plate 309. In this case, if the donut-shaped member is made of a material having poor thermal conductivity, the heat blocking property can be further increased. For example, if the donut-shaped member is formed of an aluminum material, the thermal conductivity is 100 to 200 [W / mk]. However, if the member is made of an iron-based material, the thermal conductivity is 10 to 20 [W / m]. mK] grade materials are available. In addition, so-called engineering plastics having high compression durability at high temperatures may be used. Moreover, you may arrange | position the above-mentioned donut-shaped member in the power circuit part 30 side other than the fixing | fixed part of the thermal radiation plate 309. FIG.

  Further, when the heat dissipation plate 309 has a shape as shown in FIG. 8, it is possible to simultaneously mount members other than the power circuit portion 30 on the heat dissipation plate 309. 30 or the members around the power circuit unit 30 are assembled on the heat dissipation plate 309, and then combined with the rotating electric machine, the productivity is improved.

Embodiment 3 FIG.
In the third embodiment, a plurality of heat dissipation plates are stacked and installed between the power circuit portion and the power bracket fixing boss of the rear bracket. FIG. 9 is an explanatory view showing a heat radiating plate in a rotary electric machine according to Embodiment 3 of the present invention, wherein (a) is a perspective view of the heat radiating plate, and (b) is an explanatory view explaining an attached state of the heat radiating plate. . FIG. 9 shows a state in which two heat radiation plates 3101 and 3111 are stacked. 9A and 9B, a heat radiating plate 3101 in the upper part of the drawing includes a plurality of through holes 3101a and a plurality of fin portions 3101b cut and raised at the same time when the through holes 3101a are formed. Prepare for the left side. The heat radiating plate 3111 at the bottom of the figure includes a plurality of through holes 3111a and a plurality of fin portions 3111b that are cut and raised at the same time when the through holes 3111a are formed on the right side of the through hole 3111a. The sizes of the through holes 3101a and 3101b of the heat radiating plates 3101 and 3111 and the positions where they are provided are the same.

  The heat dissipating plates 3101 and 3111 formed as described above are overlaid as shown in FIG. As a result, the fin portion 3101 b of the heat radiating plate 3101 penetrates the through hole 3111 a of the heat radiating plate 3111 and protrudes downward in the figure of the heat radiating plate 3111. As a result, the fin portions 3101b and 3111b are alternately arranged on the left and right side edge portions in the drawing of the through hole 3111a of the heat radiating plate 3111.

  As shown in FIG. 9B, the heat radiating plate 3101 and the heat radiating plate 3111 are placed on the power circuit portion fixing boss 71 of the rear bracket 7 so that the heat radiating plate 3111 is placed on the rear bracket 7 side. Then, the terminal 302 of the power circuit unit 30 is mounted on the heat dissipation plate 3101. As in the other embodiments, these are integrally fixed to the power circuit portion fixing boss 71 of the rear bracket 7 by bolts or the like.

  According to the third embodiment, the heat that is about to flow into the power circuit unit 30 from the rear bracket 7 is dispersed and radiated to the plurality of heat radiation plates 3101 and 3111, so that the amount of heat received by the power circuit unit 30 is further increased. It becomes possible to reduce.

  In addition, you may each provide a low heat conductive area | region in at least one of each surface where the heat-radiation plates accumulated contact | abut. In this case, a space allowing ventilation is created between the plurality of heat radiating plates, and the heat radiating area can be further increased, and the thermal resistance of the heat transfer path from the rear bracket 7 to the power circuit unit 30 is further increased. Therefore, the amount of heat received by the power circuit unit 30 is further reduced. In addition, since the heat radiation area that can be accommodated in the entire rotating electrical machine is expanded, the heat dissipation capability of the entire rotating electrical machine is improved.

Embodiment 4 FIG.
FIG. 10 is an explanatory view showing a heat radiating plate in a rotary electric machine according to Embodiment 4 of the present invention. In FIG. 10, each of the heat radiating plates 3121 installed between the two sets of power circuit portions 30 and the rear bracket 7 is integrally connected by a connecting portion 3121c as in the second embodiment shown in FIG. Has been. Each of the connected heat radiating plates 3121 includes a plurality of through holes 3121a as in the case of the second embodiment. In this example, the heat radiating plate 3121 is configured to be integrally connected by molding a single metal plate by press working. Further, the integrally connected heat radiating plate 3121 includes a pair of annular protrusions 3121b as thick portions for the same purpose as in the case of FIG. The shape of the annular protrusion 3121b does not have to be circular, as in the case of the first embodiment.

  In the fourth embodiment, a low heat conductive member 3131 is disposed between the annular protrusion 3121b of the heat radiating plate 312 and the heat sink 301 of the power circuit unit 30 or the terminal 302 of the power circuit unit 30, and the heat radiating plate 3121 and the rear A heat conducting member 314 is disposed between the bracket 7 and the bracket 7.

  Of the amount of heat transmitted from the rear bracket 7 to the power circuit unit 30, the ratio of the amount of heat transmitted to the power circuit unit 30 and the amount of heat transmitted to the heat radiating plate 3121 depends on the thermal resistance from the rear bracket 7 to the heat radiating surface of the heat radiating plate 3121, and the rear bracket. 7 is greatly influenced by the ratio of thermal resistance from the heat dissipation surface of the power circuit unit 30 to the power circuit unit 30. That is, by reducing the thermal resistance from the rear bracket 7 to the heat radiating surface of the heat radiating plate 3121 and increasing the thermal resistance from the rear bracket 7 to the heat radiating surface of the power circuit portion 30, the heat flow to the power circuit portion 30 is reduced. It can be made smaller. By providing the low thermal conductive member 3131 between the power circuit unit 30 and the heat radiating plate 3121, the thermal resistance from the rear bracket 7 to the power circuit unit 30 is compared with the thermal resistance from the rear bracket 7 to the heat radiating plate 3121. Greatly increased. For this reason, it is possible to further reduce the amount of heat received by the power semiconductor element of the power circuit unit 30.

  The low thermal conductive member 3131 is made of a resin material such as PPS or PBT, or a metal material having a low thermal conductivity such as stainless steel. In addition, when using a resin-based material, it is necessary to prevent charging of the members constituting the power circuit unit 30 or to connect the rear bracket 7 that is a ground potential on the circuit to the terminal 302 of the power circuit unit 30 or the like. The conductive path between the power circuit portion 30 and the rear bracket 7 is formed by using a resin containing a conductive polymer or conductive compound, or by integrally forming a metal insert member such as a metal collar.

  In addition, a heat conducting member 314 is disposed between the heat dissipation plate 3121 and the rear bracket 7. The heat conducting member 314 is formed of a metal having low hardness, a sheet made of a high heat dissipation filler, a high heat dissipation polymer and a resin, grease containing a high heat conductive compound, or the like. As described above, the low heat conductive member 3131 is disposed between the heat dissipation plate 3121 and the power circuit unit 30, and the heat conducting member 314 is disposed between the heat dissipation plate 3121 and the rear bracket 7. The thermal resistance between the heat radiating plate 3121 decreases and the thermal resistance between the heat radiating plate 3121 and the power circuit unit 30 increases.

  As a result, the heat of the rear bracket 7 can be efficiently drawn into the heat radiating plate 3121 and the amount of heat transferred to the power circuit unit 30 can be reduced. In addition, by disposing the heat conducting member 314 and the low heat conducting member 3131 in a portion where the heat radiating plate 3121, the rear bracket 7 and the power circuit unit 30 are in contact with each other, generation of foreign metal corrosion that occurs when foreign matters such as water enter. Can be prevented and reliability is improved. The heat conducting member 314 is appropriately deformed when the power circuit unit 30 and the heat radiating plate 3121 are fixed to the rear bracket 7, and the true contact area between the heat radiating plate 3121 and the rear bracket 7 is improved.

  FIG. 11 is an explanatory view for explaining a modification of the heat radiating plate and the fixing of the power circuit portion in the rotary electric machine according to Embodiment 4 of the present invention. In FIG. 11, the heat radiating plate 315 is provided with a pair of fixing portions 315d to the power circuit portion 30 and a pair of fixing portions 315e of the heat radiating plate 315 and a rear bracket (not shown). This heat radiating plate 315 is a heat radiating plate (only one heat radiating plate is shown) installed between two sets of power circuit portions 30 (only one power circuit portion is shown) and the rear bracket 7. ) Are integrally connected by the connecting portion 315c as in the second embodiment shown in FIG. Each of the connected heat radiating plates 315 includes a plurality of through holes 315a as in the case of the second embodiment. In this example, the heat dissipating plate 315 is configured to be integrally connected by molding a single metal plate by press working.

  Although not shown, as in the case of FIG. 10, a low heat conduction member 3131 similar to the above is inserted between the power circuit unit 30 and the fixing part 315 d of the heat radiating plate 315, and the fixing part of the radiating plate 315 is fixed. A heat conducting member 314 similar to that described above is inserted between 315e and the rear bracket 7.

  By separately providing the heat radiating plate 315 with a pair of fixing portions 315d to the power circuit portion 30 and a pair of fixing portions 315e with the heat radiating plate 315 and a rear bracket (not shown), the power circuit portion is separated from the rear bracket 7. The thermal resistance to 30 can be further increased, and the thermal resistance from the rear bracket 7 to the heat radiating plate 315 can be kept small.

  That is, the difference between the thermal resistance from the rear bracket 7 to the power circuit unit 30 and the thermal resistance from the rear bracket 7 to the heat radiating plate 315 is increased, and the amount of heat received by the power circuit unit 30 is further decreased. In this structure, the thermal resistance from the rear bracket 7 to the power circuit unit 30 is the largest among the thermal resistances from the rear bracket 7 to the power circuit unit 30, and the thermal resistance from the rear bracket 7 to the heat radiation plate 315 and The thermal resistance from the heat radiation plate 315 to the power circuit unit 30 is smaller than the thermal resistance from the rear bracket 7 to the power circuit unit 30.

  In a rotating electrical machine that starts and regenerates, such as a motor generator, a current of several tens [A] is supplied to the power circuit unit 30 and large heat is generated. At this time, by adopting the above-described structure, the power circuit unit 30 prevents heat from being received from the rear bracket 7 and releases heat generated by the power circuit unit 30 to the heat radiating plate 315, thereby reducing the temperature rise of the power semiconductor element. is there. By providing the low heat conductive member 3131 between the heat dissipation plate 315 and the power circuit unit 30 as described above, it is possible to further prevent the power circuit unit 30 from receiving heat. Further, by providing the heat conducting member 314 between the heat radiating plate 315 and the rear bracket 7 as described above, even when the amount of heat received from the rear bracket 7 to the heat radiating plate 315 increases, the temperature of the power circuit unit 30 is increased. While suppressing the rise, the heat dissipation performance of the entire rotating electrical machine can be improved.

  It should be noted that within the scope of the present invention, the embodiments can be freely combined, and the embodiments can be appropriately modified or omitted.

DESCRIPTION OF SYMBOLS 100 Rotating electrical machine 1 Rotor shaft 2 Field iron core 3 Field winding 4 Slip ring 5 Stator 6 Front bracket 7 Rear bracket 8 Brush 80 Brush holder 10 Rotor 12, 13 Cooling fans 19a, 19b Bearing 20 Pulley 30 Power circuit Part 31 Field circuit part 32 Control circuit part 51 Armature winding 200 Controller 201 Controller cover 30a Power semiconductor element 3a Semiconductor element 304 Signal line connection terminal 321 Control circuit board 312 AC side terminal 322 Lead wire connection part 323 Case 311 Case 313 Heat sink 302 Terminal 303 Case
305, 306, 307, 308, 309, 3101 Heat radiation plate 3111, 3121, 315 Heat radiation plate 305a, 306a, 307a, 308a, 309a Through hole 3101a, 3111a, 3121a, 315a 309b, 312b Annular projection 309c Connecting portion 3131 Low heat conducting member 314 Thermally conducting member 315d, 315e Fixed portion

Claims (8)

A rotor shaft rotatably supported by the housing;
A stator fixed to the housing and having an armature winding;
A rotor fixed to the rotor shaft and having a field core and a field winding;
A power circuit section composed of a MOS-FET acting as an inverter that performs power conversion between the armature winding and an external DC power source;
A wiring member provided in the power circuit section;
A heat sink for heat dissipation provided in the power circuit section;
With
A rotating electrical machine in which the power circuit portion is mounted on the housing by fixing the heat sink or the wiring member to the housing,
A heat dissipation plate inserted between the heat sink or the wiring member and the housing ,
Between the heat radiating plate and the heat sink or the wiring member, it is configured to have a thermal resistance larger than the thermal resistance between the radiating plate and the housing.
Rotating electric machine characterized by that. The heat radiating plate includes a fin portion cut and raised at the time of forming the through hole and the through hole,
The rotating electrical machine according to claim 1. The heat dissipation plate has a low heat conduction region on the surface facing the heat sink or the wiring member.
The rotating electrical machine according to claim 1 or 2, characterized in that A plurality of the power circuit portions including the wiring member and the heat sink are provided,
The heat dissipation plate is configured by connecting a plurality of heat dissipation plates individually corresponding to the plurality of power circuit portions,
The rotating electrical machine according to any one of claims 1 to 3, wherein The heat dissipation plate is
Consists of multiple heat dissipation plates,
The rotating electrical machine according to any one of claims 1 to 4, wherein the rotating electrical machine is provided. A low thermal conductivity member having a low thermal conductivity inserted between the heat sink or the wiring member and the heat dissipation plate,
The rotating electrical machine according to any one of claims 1 to 5, wherein A heat conducting member having a high thermal conductivity inserted between the housing and the heat dissipation plate;
The rotating electrical machine according to any one of claims 1 to 6, wherein The heat dissipation plate is
A fixing portion fixed to the heat sink or the wiring member;
A fixing portion provided at a position different from the fixing portion and fixed to the housing;
With
The rotating electrical machine according to any one of claims 1 to 7, wherein

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