Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
       [0001]    The present invention relates to a controller-integrated rotary electric machine in which a rotary electric machine and a controller for controlling the rotary electric machine are integrated with each other. 
       2. Description of the Related Art 
       [0002]    A controller-integrated rotary electric machine equipped in a vehicle such as an automobile is provided with a power conversion circuit that performs power conversion between an armature winding of the rotary electric machine and a battery provided outside the rotary electric machine. This power conversion circuit normally has a plurality of power modules containing switching elements configured from semiconductors. The power conversion circuit is operated as an inverter or converter by control of a gate signal applied to each of the gates of these switching elements. 
         [0003]    When operating the rotary electric machine as a motor, the power conversion circuit is operated as an inverter. The inverter in this case converts direct current power of the battery into alternating current power and supplies the alternating current power to the armature winding of the rotary electric machine. 
         [0004]    Meanwhile, when operating the rotary electric machine as a generator, the power conversion circuit is operated as a converter. The converter in this case converts alternating current power induced by the armature winding of the rotary electric machine into direct current power and supplies the direct current power to the battery. 
         [0005]    Such a conventional controller-integrated rotary electric machine with the foregoing configuration is provided with a positive-side power input/output terminal for the armature winding of the rotary electric machine. Furthermore, a negative-side power input/output terminal for the plurality of power modules is electrically connected to a bracket rear made of die-cast aluminum through a heat sink made of die-cast aluminum and is also electrically connected to the negative electrode terminal of the battery by using one end of the bracket rear (see Japanese Patent Application Publication No. 2015-126602, for example). 
       SUMMARY OF THE INVENTION 
       [0006]    Unfortunately, the prior art faces the following problems. The bracket rear made of die-cast aluminum is exposed to the outside in this conventional device, exposing the negative electrode portion as well. Therefore, it is important to improve vibration resistance of the positive-side power input/output terminal and the negative-side power input/output terminal. 
         [0007]    The present invention was contrived in order to solve the foregoing problems inherent in conventional rotary electric machines, and an objet thereof is to provide a controller-integrated rotary electric machine capable of ensuring vibration resistance. 
         [0008]    A controller-integrated rotary electric machine according to the present invention is a controller-integrated rotary electric machine having a power circuit portion provided between an external power source and a stator winding of a rotary electric machine main body, wherein the power circuit portion includes: a positive-side power input/output terminal and a negative-side power input/output terminal that are electrically connected to the external power source; a power module that is connected to the external power source by the positive-side power input/output terminal and the negative-side power input/output terminal, is also connected to the stator winding, and performs power conversion between the external power source and the stator winding; and a single heat sink that cools the power module, the positive-side power input/output terminal being fixed to the single heat sink via an insulating material, and the negative-side power input/output terminal being fixed directly to the single heat sink. 
         [0009]    According to the present invention, the positive-side power input/output terminal and the negative-side power input/output terminal are configured to be fixed to the same single heat sink. Therefore, a controller-integrated rotary electric machine capable of ensuring vibration resistance can be obtained. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a longitudinal cross-sectional diagram of a controller-integrated rotary electric machine according to Embodiment 1 of the present invention; 
           [0011]      FIG. 2  is a circuit diagram of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention; 
           [0012]      FIG. 3  is a partially broken side view of a rear, showing a configuration of a power circuit portion of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention; 
           [0013]      FIG. 4  is a front view of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention; 
           [0014]      FIG. 5  is a side view of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention; 
           [0015]      FIG. 6  is a cross-sectional diagram of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention; 
           [0016]      FIG. 7  is a side view of a controller-integrated rotary electric machine according to Embodiment 2 of the present invention; 
           [0017]      FIG. 8  is a front view of a controller-integrated rotary electric machine according to Embodiment 3 of the present invention; 
           [0018]      FIG. 9  is a side view of the controller-integrated rotary electric machine according to Embodiment 3 of the present invention; 
           [0019]      FIG. 10  is a front view of a controller-integrated rotary electric machine according to Embodiment 4 of the present invention; and 
           [0020]      FIG. 11  is a front view showing a harness installed in the controller-integrated rotary electric machine according to Embodiment 4 of the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    Preferred embodiments of a controller-integrated rotary electric machine according to the present invention are described hereinafter with reference to the drawings. 
       Embodiment 1 
       [0022]      FIG. 1  is a longitudinal cross-sectional diagram of a controller-integrated rotary electric machine according to Embodiment 1 of the present invention. As shown in  FIG. 1 , a controller-integrated rotary electric machine  100  for a vehicle is provided with a front bracket  1 , a stator core  3  supported by a rear bracket  2 , and a rotor core  4  inserted into an internal space of the stator core  3 . The rotor core  4  has a plurality of rotor magnetic poles that face an inner peripheral surface of the stator core  3  with a gap therebetween. 
         [0023]    A stator winding  300 , an armature winding, has a coil piece thereof inserted into a slot of the stator core  3  and is fixed to the stator core  3 . In this Embodiment 1, the stator winding  300  has a 6-phase connection. 
         [0024]    A rotor winding  7  functioning as a field winding is fixed to the rotor core  4 . The stator core  3  and the stator winding  300  configure a stator  5  of a rotary electric machine main body  102 , whereas the rotor core  4  and the rotor winding  7  configure a rotor  13  of the rotary electric machine main body  102 . 
         [0025]    The front bracket  1  and the rear bracket  2  are tightened by a plurality of bolts  101  in a direction in which these brackets approach each other, strongly holding the stator core  3  therebetween. 
         [0026]    A rotor shaft  6  passing through the center of the rotor core  4  is supported in a rotatable manner by a front-side bearing  61  supported by the front bracket  1  and a rear-side bearing  62  supported by the rear bracket  2 . 
         [0027]    A front-side cooling fan  51  and a rear-side cooling fan  52  are fixed to a front-side end surface and a rear-side end surface of the rotor core  4  and rotate together with the rotor core  4 , thereby introducing air in from the outside of the front bracket  1  and the rear bracket  2 . As a result, the inside of the rotary electric machine main body  102  is cooled. 
         [0028]    A pulley  12  is fixed to a front-side end portion of the rotor shaft  6 . A transfer belt (not shown) that moves in conjunction with a rotating shaft of an engine is wrapped around the pulley  12 . A pair of slip rings  8  fixed to the peripheral surface of the rotor shaft  6  is in sliding contact with a pair of brushes  9  supported by a brush holder  90 . 
         [0029]    A magnetic pole position detection sensor  10  configured by a synchronous resolver has a sensor rotor  111  fixed to a rear-side end portion of the rotor shaft  6 , a sensor stator  112  facing the sensor rotor  111  and fixed to the rear bracket  2 , and a sensor winding  113  fixed to the sensor stator  112 . 
         [0030]    A control circuit board  40  with a control circuit is stored in a board storage case  41  made of resin. The control circuit provided in the control circuit board  40  controls the switching operations of power modules  21  described hereinafter. The board storage case  41  is fixed to an outer surface portion of a heat sink  23 . 
         [0031]    A power circuit portion  20  is fixed outside the rear bracket  2  and has a power conversion circuit that performs power conversion between the stator winding  300  functioning as an armature winding and a battery, not shown. This power conversion circuit is configured with six power modules  21  described hereinafter and is operated as a 6-phase inverter or a 6-phase converter. 
         [0032]      FIG. 2  is a circuit diagram of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention. As shown in  FIG. 2 , in Embodiment 1, each of the power modules  21  has two serially-connected semiconductor switching elements and two diodes connected, respectively, antiparallel to the semiconductor switching elements, and these switching elements and the diodes are sealed with resin into one package. 
         [0033]    The two semiconductor switching elements sealed in each power module  21  are connected in series, as described above. One of these semiconductor switching elements and the diode connected antiparallel thereto configure a positive pole-side arm corresponding to one phase of a 6-phase bridge circuit. The other semiconductor switching element and the diode connected antiparallel thereto configure a negative pole-side arm corresponding to one phase. 
         [0034]    Each series connection point between the two semiconductor switching elements is connected to the stator winding  300  corresponding to one phase of a 6-phase stator winding. Therefore, the six power modules  21  configured as described above are connected respectively to terminals  22   a  that are connected to a B terminal  24  described hereinafter. 
         [0035]      FIG. 3  is a partially broken side view of the rear, showing a configuration of the power circuit portion of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention. As shown in  FIG. 3 , the power circuit portion  20  has the six power modules  21  configuring the 6-phase power conversion circuit and controlling conduction of the stator winding  300 , the heat sink  23  on which these power modules  21  are mounted with insulating layers (not shown) therebetween, a positive-side power input/output terminal bolt  11  that is electrically connected to the positive side of the battery, the B terminal  24  and a B bus bar  30  that are electrically connected to the positive-side power input/output terminal bolt  11 , and a power circuit case  25 . 
         [0036]    As shown in  FIG. 1 , the heat sink  23  is made of metal such as die-cast aluminum and has a through-hole  231  in the middle. On the front surface of the heat sink  23 , multiple cooling fins  23   a  extending in an axial direction are formed integrally at the stator side of the rotary electric machine main body  102 . The rotor shaft  6  passes through the through-hole  231  of the heat sink  23 . 
         [0037]    As shown in  FIG. 3 , the power circuit case  25  is made of resin and has an annular outer case portion  251  and an annular inner case portion  252 . The inner case portion  252  has an inner wall  255  surrounding a through-hole  254  of the inner case portion  252 . The inner wall  255  configures the inner wall of the power circuit case  25 . 
         [0038]    The power circuit case  25  is fixed to a rear-side front surface of the heat sink  23 , thereby configuring a power module storage portion  257  surrounded by the outer case portion  251  and the inner case portion  252  of the power circuit case  25  and the rear-side front surface of the heat sink  23 . 
         [0039]    As shown in  FIG. 3 , the six power modules  21  described above are stored in the power module storage portion  257  and placed to form an opposite C-shape with spaces therebetween. In addition, control circuit board connectors  260  connected to the control circuit board  40  are inserted into the power module storage portion  257 . 
         [0040]    The control circuit board connectors  260  each apply a gate signal, which is sent from the control circuit of the control circuit board  40 , to the gates of the semiconductor switching elements of each power module  21 . 
         [0041]    A power circuit waterproof resin  28  is packed in the power module storage portion  257  in which the power modules  21  and the control circuit board connectors  260  are stored. The power modules  21  and the control circuit board connectors  260 , therefore, are embedded in the power circuit waterproof resin  28  and protected from water by the power circuit waterproof resin  28 . 
         [0042]    The B terminal  24 , which functions as a terminal connected electrically to the positive electrode of the outside battery, is molded in the inner case portion  252  of the power circuit case  25  and a case coupling portion  253 . 
         [0043]    The B terminal  24  is electrically or mechanically connected to the terminals  22   a  of the six power modules  21  and terminals  260   a  of the control circuit board connectors  260  by welding or soldering. Note that the B terminal  24  is exposed on an upper surface of the case coupling portion  253  of the power circuit case  25 . 
         [0044]    The bus bar (referred to as “B bus bar” hereinafter)  30  connected electrically to the positive electrode of the outside battery is connected electrically to the positive-side power input/output terminal bolt  11  and fixed to the heat sink  23  through the power circuit case  25  configured as an insulating material. 
         [0045]      FIG. 4  is a front view of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention.  FIG. 5  is a side view of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention.  FIG. 6  is a cross-sectional diagram of the controller-integrated rotary electric machine according to Embodiment 1 of the present invention, taken along A-A′ of  FIG. 4 . 
         [0046]    The positive-side power input/output terminal bolt  11  and a negative-side power input/output terminal bolt  71  are in a positional relation shown in  FIGS. 4 and 5 . As shown in  FIG. 6 , the negative-side power input/output terminal bolt  71  is fixed directly to the heat sink  23 , whereas the positive-side power input/output terminal bolt  11  is fixed to the heat sink  23  through the power circuit case  25  configured as an insulating material. 
         [0047]    In the controller-integrated rotary electric machine  100  according to Embodiment 1 of the present invention having the foregoing configuration, the positive-side power input/output terminal bolt  11  is electrically connected to the positive side of the battery provided on the outside of the controller-integrated rotary electric machine  100 , through a battery harness or the like (not shown). 
         [0048]    The pulley  12  is coupled, through a belt, to a pulley on an internal combustion engine (not shown) that is provided at the output shaft of the internal combustion engine. 
         [0049]    When the controller-integrated rotary electric machine  100  is operated as a motor, the power conversion circuit configured by the power modules  21  is operated as an inverter. Specifically, by having the semiconductor switching elements of the power modules  21  switch-controlled with a gate signal from the control circuit provided in the control circuit board  40 , the power conversion circuit is operated as an inverter. 
         [0050]    Consequently, direct current power is input from the battery to the terminals  22   a  of the power modules  21  through the positive-side power input/output terminal bolt  11 , the B terminal  24 , and the B bus bar  30 . The input direct current power is converted into 6-phase alternating current power by the inverter configured by the power modules  21 . Furthermore, the resultant 6-phase alternating current power is supplied to the winding of each of the phases of the 6-phase stator winding  300  through terminals  22   b  of the power modules  21 . 
         [0051]    As a result, the rotor  13  is driven by the interaction between a rotating magnetic field generated by the stator winding  300  and a magnetic field generated by the rotor winding (field winding)  7  provided in the rotor  13 . Furthermore, driving the rotor  13  transmits power from the pulley  12  to the internal combustion engine through the belt. 
         [0052]    When, on the other hand, the controller-integrated rotary electric machine  100  is operated as a generator, the power of the internal combustion engine is transmitted to the pulley  12  through the belt to drive the rotor  13 . In this case, the power conversion circuit configured by the power modules  21  is operated as a converter. 
         [0053]    Specifically, by having the semiconductor switching elements of the power modules  21  switch-controlled with a gate signal from the control circuit provided in the control circuit board  40 , the power conversion circuit is operated as a converter. 
         [0054]    The alternating current power induced by each phase winding of the stator winding  300  is applied to each of the power modules  21  via the terminals  22   b  of the power modules  21 . As a result, the alternating current power is converted into direct current power by the converter configured with the power modules  21 . In addition, the resultant direct current power is supplied from the terminals  22   a  of the power modules  21  to the battery via the B bus bar  30 , the B terminal  24 , a spacer  42 , and a nut  36 . 
         [0055]    In the controller-integrated rotary electric machine  100  according to Embodiment 1 of the present invention, the positive-side power input/output terminal and the negative-side power input/output terminal each have a fixed structure fixed to the same single heat sink, as described above. Therefore, vibration resistance can be ensured. 
         [0056]    The cooling efficiency of these terminals can be improved due to the presence of these fixed structures. Therefore, thermal expansion or thermal compression does not occur easily on the nut  36  during a heat cycle, preventing loosening of the nut  36 . 
         [0057]    In addition, the controller-integrated rotary electric machine  100  according to Embodiment 1 of the present invention has a space portion formed between the positive-side power input/output terminal and the negative-side power input/output terminal, as shown in  FIG. 4 . Therefore, even when the controller-integrated rotary electric machine  100  is submerged, insulation thereof can always be ensured without having water pooling therein. 
         [0058]    Therefore, when the controller-integrated rotary electric machine needs to have higher voltage (e.g., approximately 50 V), the foregoing configuration can eliminate the possibility of electrical shock to a human who disconnects the rotary electric machine to conduct vehicle maintenance. 
         [0059]    The presence of such a space portion allows the positive-side power input/output terminal bolt or a positive-side power supply harness on the vehicle side to fall into the space portion upon collision of the vehicle. Consequently, the positive-side power input/output terminal bolt or the positive-side power supply harness on the vehicle side does not short-circuit with the negative-side power input/output terminal bolt, preventing destruction by fire and achieving a beneficial effect on collision safety. 
         [0060]    As described above, Embodiment 1 provides the configuration in which the positive-side power input/output terminal and the negative-side power input/output terminal are fixed to a single heat sink. Embodiment 1, therefore, can realize a controller-integrated rotary electric machine capable of ensuring vibration resistance. 
         [0061]    Embodiment 1 also provides the configuration in which the space portion is formed between the positive-side power input/output terminal bolt and the negative-side power input/output terminal bolt. Therefore, even when the controller-integrated rotary electric machine is submerged, the controller-integrated rotary electric machine can always ensure insulation without having water pooling therein. 
         [0062]    Moreover, the presence of such a space portion prevents not only short circuit between the positive side and the negative side but also destruction by fire even upon collision of the vehicle, contributing to the improvement collision safety. 
         [0063]    Embodiment 2 
         [0064]      FIG. 7  is a side view of a controller-integrated rotary electric machine according to Embodiment 2 of the present invention. As shown in  FIG. 7 , unlike the configuration shown in  FIG. 5  according to Embodiment 1 described above, a controller-integrated rotary electric machine  100  according to Embodiment 2 of the present invention has the positive-side power input/output terminal bolt  11  placed at the rear side. 
         [0065]    As a result of placing the positive-side power input/output terminal bolt  11 , the positive-side power input/output terminal bolt  11  and the negative-side power input/output terminal bolt  71  can be separated from each other in the axial direction of the rotor shaft of the rotary electric machine. As a result, insulation between the positive side and the negative side can be ensured even upon entry of foreign substances. 
         [0066]    As described above, Embodiment 2 further has the configuration in which the positive-side power input/output terminal and the negative-side power input/output terminal are separated in the axial direction. The configuration of Embodiment 2 can therefore realize a controller-integrated rotary electric machine with more improved insulation. 
       Embodiment 3 
       [0067]      FIG. 8  is a front view of a controller-integrated rotary electric machine according to Embodiment 3 of the present invention.  FIG. 9  is a side view of the controller-integrated rotary electric machine according to Embodiment 3 of the present invention. 
         [0068]    A controller-integrated rotary electric machine  100  according to Embodiment 3 of the present invention has the positive-side power input/output terminal bolt  11  extended in the axial direction and the negative-side power input/output terminal bolt  71  extended in the radial direction of the rotary electric machine. In this arrangement as well, the positive-side power input/output terminal bolt  11  and the negative-side power input/output terminal bolt  71  are separated from each other in the radial direction. Therefore, as with the arrangement described in Embodiment 2, the configuration of Embodiment 3 can ensure insulation against entry of foreign substances. 
         [0069]    Although not shown, the same effects as the arrangement shown in  FIGS. 8 and 9  can be achieved with an arrangement different from that shown in  FIGS. 8 and 9 , in which the positive-side power input/output terminal bolt  11  is extended in the radial direction and the negative-side power input/output terminal bolt  71  is extended in the axial direction. 
         [0070]    As described above, Embodiment 3 has the configuration in which the positive-side power input/output terminal and the negative-side power input/output terminal are extended in different directions and separated from each other. Therefore, as with Embodiment 2, the configuration of Embodiment 3 can realize a controller-integrated rotary electric machine with more improved insulation. 
       Embodiment 4 
       [0071]      FIG. 10  is a front view of a controller-integrated rotary electric machine according to Embodiment 4.  FIG. 11  is a front view showing a harness installed in the controller-integrated rotary electric machine according to Embodiment 4 of the present invention. 
         [0072]    A harness mount of the positive-side power input/output terminal is provided with an odd number of depressions that are arranged at approximately equal intervals. On the other hand, a harness mount of the negative-side power input/output terminal is provided with an even number of depressions that are arranged at approximately equal intervals. In the examples shown in  FIGS. 10 and 11 , the harness mount of the positive-side power input/output terminal is provided with three depressions, and the harness mount of the negative-side power input/output terminal is provided with two depressions. 
         [0073]    With these different installation structures of the both terminals, improper mechanical assembly therebetween can be prevented from occurring in market maintenance, preventing reverse connection of the battery. Consequently, smoke emission and ignition can be prevented beforehand. 
         [0074]    Although not shown, the same effects as those of the configuration shown in  FIGS. 10 and 11  can be achieved by creating a configuration different from that shown in  FIGS. 10 and 11 , in which the harness mount of the positive-side power input/output terminal is provided with an even number of depressions that are arranged at approximately equal intervals and the harness mount of the negative-side power input/output is provided with an odd number of depressions that are arranged at approximately equal intervals. 
         [0075]    According to such a configuration in which the harness mounts are each provided with depressions arranged at approximately equal intervals, the tightening torque generated by attaching the harnesses can act substantially evenly on the depressions, preventing damage to the depressions. 
         [0076]    According to Embodiment 4, as described above, the number of depressions provided is different between the harness mounts of the positive-side power input/output terminal and the negative-side power input/output terminal, and the depressions are arranged at approximately equal intervals. The configuration of Embodiment 4, therefore, can prevent reverse connection of the battery and damage to the depressions that could be caused by the tightening torque.

Technology Category: 5