JP2016154445A - Rotary electric machine, and vehicle with the rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary electric machine capable of attaining noise reduction.SOLUTION: In the rotary electric machine comprising stator coils of wave winding and a rotor, a crossover conductor 233b connects slot conductors over slots by Np=N+1 (Np: slot pitch, N: slot number per pole) at one coil end and over slots by Np=N-1 at the other coil end. The stator coil includes one slot conductor group 234 formed from slot conductors 233a of the same phase, and the slot conductor 233a is inserted in such a manner that layers L1 to L4 are adjacent within a slot 237. When the number of layers is defined as 2×NL, a slot number Ns is set as Ns=NSPP+NL (NSPP: slot number per pole and per phase). The rotor includes a magnetic resistance change part at a position circumferentially deviated from a (q) axis by a predetermined amount, and the deviation amount is made different in accordance with a position of an auxiliary salient pole part in such a manner that torque pulsations during electrification are cancelled by each other.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a rotating electrical machine and a vehicle including the rotating electrical machine.

  As a winding technique of a rotating electrical machine used for driving a vehicle, a technique as described in Patent Document 1 is known. As a technique related to the rotor, a technique as described in Patent Document 2 is also known.

US Pat. No. 6,894,417 JP 2010-98830 A

  A rotating electric machine mounted on an electric vehicle or the like is required to have low noise. Therefore, the present invention aims to reduce the noise of a rotating electrical machine.

  The rotating electrical machine according to the present invention includes a stator core formed with a plurality of slots, a slot conductor inserted into each slot of the stator core and constituting any one of a plurality of layers, and a different slot. Stator windings having a plurality of wave windings composed of crossing conductors that connect the same side ends of the inserted slot conductors to form a coil end, and a gap with respect to the stator core And a rotor having a plurality of magnets, a plurality of magnetic auxiliary salient pole portions formed between the poles of the magnets, and a first magnetic gap provided on a side surface of the magnets. The crossover conductor has a slot pitch Np = N + 1 across one coil end and a slot pitch Np = N−1 across the slot when the number of slots per pole is N. Slot The stator windings connect the conductors, and the stator winding has a group of slot conductor groups each composed of a plurality of slot conductors of the same phase, and the plurality of slot conductors of the slot conductor group are continuous in the circumferential direction of the stator core. Ns = NSPP + NL when the number of slots per phase is NSPP and the number of layers is 2 × NL. A second magnetic air gap is formed in the magnetic auxiliary salient pole portion of the rotor symmetrically with respect to the d axis and asymmetric with respect to the q axis, and the second magnetic air gap is formed. Is provided to be shifted to the right or left side with respect to the q axis so that torque pulsation during energization is canceled in a cross section perpendicular to the axial direction, and the pole pitch of the magnet is set to τp, The first magnetic sky provided; When the .tau.g an angle combined bets, magnets Anakyoku arc degree .tau.g / .tau.p is characterized in that 0.9 to 0.5.

  A vehicle according to the present invention includes the above-described rotating electrical machine, a battery that supplies DC power, and a converter that converts the DC power of the battery into AC power and supplies the AC power to the rotating electrical machine, and drives the torque of the rotating electrical machine. It is used as a force.

  According to the present invention, noise reduction can be achieved in a rotating electrical machine and a vehicle including the rotating electrical machine.

The figure which shows schematic structure of a hybrid type electric vehicle. The circuit diagram of the power converter device 600. FIG. Sectional drawing of the rotary electric machine 200. FIG. The figure which shows the rotor core 252. FIG. Sectional drawing of the stator 230 and the rotor 250. FIG. The perspective view of the stator 230. FIG. The connection diagram of the stator winding | coil 238. FIG. The figure which shows the detailed connection of a U-phase winding. The enlarged view of a part of U1-phase winding group. The enlarged view of a part of U2 phase winding group. The layout of slot conductor 233a. The figure explaining arrangement | positioning of the slot conductor 233a. FIG. 4 is a partially enlarged cross-sectional view of a stator 230 and a rotor 250. The figure explaining reluctance torque. The figure which shows magnetic flux distribution at the time of non-energization. The figure explaining the cogging torque reduction method. The figure which shows the relationship between ratio of magnet pole arc degree (tau) m / (tau) p, and conging torque. The figure which shows the waveform of a cogging torque. The figure which shows an induced voltage waveform. The figure which shows the harmonic analysis result of an induced voltage waveform. The figure which shows the torque waveform at the time of supplying an alternating current. The figure which shows the harmonic analysis result of a torque waveform. The figure which shows the annular | circular 0th vibration mode of a stator. The figure which shows the annular | circular 6th vibration mode of a stator. The figure which shows the vibration mode which has an annular | circular 6th order component of a stator, and a phase reverses in the axial direction both ends. The figure which shows the detailed connection of the U-phase winding in 2nd Embodiment. The figure which shows arrangement | positioning of the slot conductor 233a in 2nd Embodiment. The figure which shows a part of detailed connection of the U-phase winding in 3rd Embodiment. The figure which shows arrangement | positioning of the slot conductor 233a in 3rd Embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

[First Embodiment]
As described below, the rotating electrical machine according to the present invention can reduce noise by reducing torque ripple. Therefore, for example, it is suitable as a driving motor for an electric vehicle. The rotating electrical machine according to the present invention can be applied to a pure electric vehicle that runs only by the rotating electrical machine and a hybrid type electric vehicle that is driven by both the engine and the rotating electrical machine. Hereinafter, a hybrid type electric vehicle is taken as an example. explain.

  FIG. 1 is a diagram showing a schematic configuration of a hybrid electric vehicle equipped with a rotating electrical machine according to an embodiment of the present invention. The vehicle 100 is mounted with an engine 120, a first rotating electrical machine 200, a second rotating electrical machine 202, and a battery 180. The battery 180 supplies DC power to the rotating electrical machines 200 and 202 via the power converter 600 when the driving force by the rotating electrical machines 200 and 202 is required, and receives DC power from the rotating electrical machines 200 and 202 during regenerative travel. . Transfer of direct-current power between the battery 180 and the rotating electrical machines 200 and 202 is performed via the power converter 600. Although not shown, the vehicle is equipped with a battery that supplies low-voltage power (for example, 14 volt system power) and supplies DC power to a control circuit described below.

  Rotational torque generated by engine 120 and rotating electrical machines 200 and 202 is transmitted to front wheel 110 via transmission 130 and differential gear 160. The transmission 130 is controlled by a transmission control device 134, and the engine 120 is controlled by an engine control device 124. The battery 180 is controlled by the battery control device 184. Transmission control device 134, engine control device 124, battery control device 184, power conversion device 600 and integrated control device 170 are connected by communication line 174.

  The integrated control device 170 is a higher-level control device than the transmission control device 134, the engine control device 124, the power conversion device 600, and the battery control device 184. The transmission control device 134, the engine control device 124, and the power conversion device 600. And information representing each state of the battery control device 184 is received from each of them via the communication line 174. The integrated control device 170 calculates a control command for each control device based on the acquired information. The calculated control command is transmitted to each control device via the communication line 174.

  The high voltage battery 180 is formed of a secondary battery such as a lithium ion battery or a nickel metal hydride battery, and outputs a high voltage DC power of 250 volts to 600 volts or more. The battery control device 184 outputs the charge / discharge status of the battery 180 and the state of each unit cell battery constituting the battery 180 to the integrated control device 170 via the communication line 174.

  When integrated control device 170 determines that charging of battery 180 is necessary based on information from battery control device 184, integrated control device 170 issues an instruction for power generation operation to power conversion device 600. The integrated control device 170 mainly manages the output torque of the engine 120 and the rotating electrical machines 200 and 202, and calculates the total torque and torque distribution ratio between the output torque of the engine 120 and the output torque of the rotating electrical machines 200 and 202. And a control command based on the calculation processing result is transmitted to the transmission control device 134, the engine control device 124, and the power conversion device 600. Based on the torque command from the integrated control device 170, the power conversion device 600 controls the rotating electrical machines 200 and 202 so that torque output or generated power is generated as commanded.

  The power converter 600 is provided with a power semiconductor that constitutes an inverter for operating the rotating electrical machines 200 and 202. The power conversion device 600 controls the switching operation of the power semiconductor based on a command from the integrated control device 170. By the switching operation of the power semiconductor, the rotary electric machines 200 and 202 are operated as an electric motor or a generator.

When the rotary electric machines 200 and 202 are operated as an electric motor, DC power from the high-voltage battery 180 is supplied to the DC terminal of the inverter of the power conversion device 600. The power conversion device 600 controls the switching operation of the power semiconductor, converts the supplied DC power into three-phase AC power, and supplies it to the rotating electric machines 200 and 202. On the other hand, when the rotating electrical machines 200 and 202 are operated as a generator, the rotors of the rotating electrical machines 200 and 202 are rotationally driven with a rotational torque applied from the outside, and the stator windings of the rotating electrical machines 200 and 202 are three-phased. AC power is generated.
The generated three-phase AC power is converted into DC power by the power converter 600, and the DC power is supplied to the high-voltage battery 180, whereby the battery 180 is charged.

  FIG. 2 shows a circuit diagram of the power converter 600 of FIG. The power conversion device 600 is provided with a first inverter device for the rotating electrical machine 200 and a second inverter device for the rotating electrical machine 202. The first inverter device includes a power module 610, a first drive circuit 652 that controls the switching operation of each power semiconductor 21 of the power module 610, and a current sensor 660 that detects the current of the rotating electrical machine 200. . The drive circuit 652 is provided on the drive circuit board 650.

  On the other hand, the second inverter device includes a power module 620, a second drive circuit 656 that controls the switching operation of each power semiconductor 21 in the power module 620, and a current sensor 662 that detects the current of the rotating electrical machine 202. ing. The drive circuit 656 is provided on the drive circuit board 654. The control circuit 648 provided on the control circuit board 646, the capacitor module 630, and the transmission / reception circuit 644 mounted on the connector board 642 are commonly used by the first inverter device and the second inverter device.

  The power modules 610 and 620 operate according to drive signals output from the corresponding drive circuits 652 and 656, respectively. Each of the power modules 610 and 620 converts DC power supplied from the battery 180 into three-phase AC power and supplies the power to stator windings that are armature windings of the corresponding rotating electric machines 200 and 202. In addition, the power modules 610 and 620 convert AC power induced in the stator windings of the rotating electrical machines 200 and 202 into DC and supply it to the battery 180.

  The power modules 610 and 620 include a three-phase bridge circuit as shown in FIG. 2, and series circuits corresponding to the three phases are electrically connected in parallel between the positive electrode side and the negative electrode side of the battery 180, respectively. ing. Each series circuit includes a power semiconductor 21 constituting an upper arm and a power semiconductor 21 constituting a lower arm, and these power semiconductors 21 are connected in series. The power module 610 and the power module 620 have substantially the same circuit configuration as shown in FIG. 2, and the power module 610 will be described as a representative here.

  In the present embodiment, an IGBT (insulated gate bipolar transistor) 21 is used as a switching power semiconductor element. The IGBT 21 includes three electrodes, a collector electrode, an emitter electrode, and a gate electrode. A diode 38 is electrically connected between the collector electrode and the emitter electrode of the IGBT 21. The diode 38 includes two electrodes, a cathode electrode and an anode electrode. The cathode electrode is the collector electrode of the IGBT 21 and the anode electrode is the IGBT 21 so that the direction from the emitter electrode to the collector electrode of the IGBT 21 is the forward direction. Each is electrically connected to the emitter electrode.

  A MOSFET (metal oxide semiconductor field effect transistor) may be used as the switching power semiconductor element. The MOSFET includes three electrodes, a drain electrode, a source electrode, and a gate electrode. In the case of a MOSFET, a parasitic diode whose forward direction is from the drain electrode to the source electrode is provided between the source electrode and the drain electrode, so there is no need to provide the diode 38 of FIG.

  Each phase arm is configured by electrically connecting the emitter electrode of the IGBT 21 and the collector electrode of the IGBT 21 in series. In the present embodiment, only one IGBT of each upper and lower arm of each phase is illustrated, but since the current capacity to be controlled is large, a plurality of IGBTs are actually connected in parallel. Has been. Below, in order to simplify description, it demonstrates as one power semiconductor.

  In the example shown in FIG. 2, each upper and lower arm of each phase is composed of three IGBTs. The collector electrode of the IGBT 21 of each upper arm of each phase is electrically connected to the positive electrode side of the battery 180, and the source electrode of the IGBT 21 of each lower arm of each phase is electrically connected to the negative electrode side of the battery 180. The middle point of each arm of each phase (the connection portion between the emitter electrode of the upper arm side IGBT and the collector electrode of the IGBT on the lower arm side) is the armature winding (fixed) of the corresponding phase of the corresponding rotating electric machine 200, 202. Is electrically connected to the secondary winding.

  The drive circuits 652 and 656 constitute a drive unit for controlling the corresponding inverter device, and generate a drive signal for driving the IGBT 21 based on the control signal output from the control circuit 648. The drive signals generated by the drive circuits 652 and 656 are output to the gates of the power semiconductor elements of the corresponding power modules 610 and 620, respectively. Each of the drive circuits 652 and 656 is provided with six integrated circuits that generate drive signals to be supplied to the gates of the upper and lower arms of each phase, and the six integrated circuits are configured as one block.

  The control circuit 648 constitutes a control unit of each inverter device, and is constituted by a microcomputer that calculates a control signal (control value) for operating (turning on / off) a plurality of switching power semiconductor elements. The control circuit 648 receives a torque command signal (torque command value) from the host controller, sensor outputs of the current sensors 660 and 662, and sensor outputs of the rotation sensors mounted on the rotating electrical machines 200 and 202. The control circuit 648 calculates a control value based on these input signals and outputs a control signal for controlling the switching timing to the drive circuits 652 and 656.

  The transmission / reception circuit 644 mounted on the connector board 642 is for electrically connecting the power conversion apparatus 600 and an external control apparatus, and communicates information with other apparatuses via the communication line 174 in FIG. Send and receive. Capacitor module 630 constitutes a smoothing circuit for suppressing fluctuations in the DC voltage caused by the switching operation of IGBT 21, and is electrically connected to the DC side terminal of first power module 610 or second power module 620. Connected in parallel.

  FIG. 3 shows a cross-sectional view of the rotating electrical machine 200 of FIG. The rotating electrical machine 200 and the rotating electrical machine 202 have substantially the same structure, and the structure of the rotating electrical machine 200 will be described below as a representative example. However, the structure shown below does not need to be employed in both the rotating electrical machines 200 and 202, and may be employed in only one of them.

  A stator 230 is held inside the housing 212, and the stator 230 includes a stator core 232 and a stator winding 238. A rotor 250 is rotatably held on the inner peripheral side of the stator core 232 through a gap 222. The rotor 250 includes a rotor core 252 fixed to the shaft 218, a permanent magnet 254, and a non-magnetic material plate 226. The housing 212 has a pair of end brackets 214 provided with bearings 216, and the shaft 218 is rotatably held by these bearings 216.

  The shaft 218 is provided with a resolver 224 that detects the position and rotation speed of the pole of the rotor 250. The output from the resolver 224 is taken into the control circuit 648 shown in FIG. The control circuit 648 outputs a control signal to the drive circuit 652 based on the fetched output. The drive circuit 652 outputs a drive signal based on the control signal to the power module 610. The power module 610 performs a switching operation based on the control signal, and converts DC power supplied from the battery 180 into three-phase AC power. This three-phase AC power is supplied to the stator winding 238 shown in FIG. 3 and a rotating magnetic field is generated in the stator 230. The frequency of the three-phase alternating current is controlled based on the output value of the resolver 224, and the phase of the three-phase alternating current with respect to the rotor 250 is also controlled based on the output value of the resolver 224.

  FIG. 4A is a perspective view showing the rotor core 252 of the rotor 250. The stator core 252 includes two types of cores 301 and 302 as shown in FIG. 4B in three stages. The axial length H2 of the core 302 is set to be substantially the same as the sum of the axial lengths H1 of the core 301.

  5A and 5B are cross-sectional views of the stator 230 and the rotor 250. FIG. 5A is a cross-sectional view taken along the line AA through the core 301 (see FIG. 3), and FIG. It is BB sectional drawing (refer FIG. 3) which passes through the part of 302. FIG. In FIG. 5, the housing 212, the shaft 218, and the stator winding 238 are not shown. On the inner peripheral side of the stator core 232, a large number of slots 237 and teeth 236 are arranged uniformly over the entire circumference. In FIG. 5, all slots and teeth are not labeled, and only some teeth and slots are represented by symbols. A slot insulating material (not shown) is provided in the slot 237, and a plurality of U-phase, V-phase, and W-phase windings constituting the stator winding 238 shown in FIG. In the present embodiment, 72 slots 237 are formed at equal intervals.

  In the vicinity of the outer periphery of the rotor core 252, a plurality of holes 253 for inserting rectangular magnets are arranged at equal intervals along the circumferential direction. Each hole 253 is formed along the axial direction, and permanent magnets 254 are embedded in the holes 253 and fixed with an adhesive or the like. The circumferential width of the hole 253 is set larger than the circumferential width of the permanent magnet 254 (254a, 254b), and the air gaps 257 on both sides of the permanent magnet 254 function as magnetic air gaps. The gap 257 may be embedded with an adhesive, or may be solidified integrally with the permanent magnet 254 with a molding resin. The permanent magnet 254 acts as a field pole of the rotor 250, and has a 12-pole configuration in this embodiment.

  The magnetization direction of the permanent magnet 254 faces the radial direction, and the direction of the magnetization direction is reversed for each field pole. That is, if the stator side surface of the permanent magnet 254a is N-pole and the surface on the shaft side is S-pole, the stator side surface of the adjacent permanent magnet 254b is S-pole and the surface on the shaft side is N-pole. . These permanent magnets 254a and 254b are alternately arranged in the circumferential direction.

  The permanent magnet 254 may be inserted into the hole 253 after being magnetized, or may be magnetized by applying a strong magnetic field after being inserted into the hole 253 of the rotor core 252. However, since the magnetized permanent magnet 254 is a strong magnet, if the magnet is magnetized before the permanent magnet 254 is fixed to the rotor 250, a strong attractive force between the rotor core 252 and the permanent magnet 254 is fixed. Occurs and hinders assembly work. In addition, due to the strong attractive force of the permanent magnet 254, dust such as iron powder may adhere to the permanent magnet 254. Therefore, when considering the productivity of the rotating electrical machine, it is preferable that the permanent magnet 254 is magnetized after being inserted into the rotor core 252.

  The permanent magnet 254 may be a neodymium-based or samarium-based sintered magnet, ferrite magnet, neodymium-based bond magnet, or the like. The residual magnetic flux density of the permanent magnet 254 is about 0.4 to 1.3 T.

  When a rotating magnetic field is generated in the stator 230 by a three-phase alternating current (by flowing through the stator winding 238), this rotating magnetic field acts on the permanent magnets 254a and 254b of the rotor 250 to generate torque. This torque is represented by the product of the component interlinked with each phase winding of the magnetic flux generated from the permanent magnet 254 and the component orthogonal to the interlinkage magnetic flux of the alternating current flowing through each phase winding. Here, since the alternating current is controlled to be sinusoidal, the product of the fundamental wave component of the interlinkage magnetic flux and the fundamental wave component of the alternating current becomes the time-average component of the torque, and the harmonic component of the interlinkage magnetic flux The product of the fundamental wave components of the alternating current becomes the torque ripple that is the harmonic component of the torque. That is, in order to reduce the torque ripple, the harmonic component of the flux linkage may be reduced. In other words, since the product of the interlinkage magnetic flux and the angular acceleration that the rotor rotates is the induced voltage, reducing the harmonic component of the interlinkage magnetic flux is equivalent to reducing the harmonic component of the induced voltage.

  FIG. 6 is a perspective view of the stator 230. In the present embodiment, the stator winding 238 is wound around the stator core 232 by wave winding. Coil ends 241 of the stator winding 238 are formed on both end surfaces of the stator core 232. Further, a lead wire 242 of the stator winding 238 is drawn out on one end face side of the stator core 232. Three lead wires 242 are drawn out corresponding to each of the U phase, the V phase, and the W phase.

  FIG. 7 is a connection diagram of the stator winding 238, showing the connection method and the electrical phase relationship of each phase winding. The stator winding 238 of the present embodiment employs a double star connection, a first star connection comprising a U1-phase winding group, a V1-phase winding group, and a W1-phase winding group, and a U2-phase winding. A second star connection composed of a wire group, a V2-phase winding group, and a W2-phase winding group is connected in parallel. Each of the U1, V1, W1 phase winding group and the U2, V2, W2 phase winding group is composed of four circumferential windings, and the U1 phase winding group includes the circumferential windings U11 to U14. The winding group has circumferential windings V11 to V14, the W1 phase winding group has circumferential windings W11 to W14, the U2 phase winding group has circumferential windings U21 to U24, and the V2 phase windings The group has the windings V21 to V24, and the W2-phase winding group has the windings W21 to W24.

  As shown in FIG. 7, the V phase and the W phase have substantially the same configuration as the U phase, and are arranged so that the phases of the voltages induced in them are shifted by 120 degrees in electrical angle. In addition, the angles of the respective windings represent relative phases. As shown in FIG. 6, in the present embodiment, the stator winding 238 employs a double star (2Y) connection connected in parallel. However, depending on the driving voltage of the rotating electrical machine, they are connected in series. It is good also as a single star (1Y) connection.

  FIG. 8 is a diagram showing the detailed connection of the U-phase winding of the stator winding 238. FIG. 8A shows the windings U13 and U14 of the U1-phase winding group, and FIG. FIG. 8C shows the windings U21 and U22 of the U2-phase winding group, and FIG. 8D shows the windings of the U2-phase winding group. U23 and U24 are shown. As described above, 72 slots 237 are formed in the stator core 232 (see FIG. 5), and reference numerals 01, 02,..., 71, 72 shown in FIG.

  Each of the windings U11 to U24 configures a coil end 241 (see FIG. 6) by connecting the same side ends of the slot conductor 233a inserted into the slot and the slot conductor 233a inserted into a different slot. And a transition conductor 233b. For example, in the case of the slot conductor 233a inserted into the slot 237 having the slot number 55 shown in FIG. 8A, the upper end of the figure is connected to the slot 237 having the slot number 60 by the crossing conductor 233b constituting the upper coil end. The lower end is connected to the upper end of the slot conductor 233a to be inserted, and conversely, the lower end is below the slot conductor 233a inserted into the slot 237 of the slot number 48 by the crossing conductor 233b constituting the lower coil end. Connected to the side edge. In this manner, the slot conductor 233a is connected by the crossing conductor 233b, whereby a wave winding is formed.

  As will be described later, in this embodiment, four slot conductors 233a are inserted in one slot side by side from the inner peripheral side to the outer peripheral side, and layer 1, layer 2, layer 3, layer 4 are sequentially arranged from the inner peripheral side. Called. In FIG. 8, the solid line portions of the windings U <b> 13, U <b> 14, U <b> 21 and U <b> 22 indicate layer 1, and the alternate long and short dash line portion indicates layer 2. On the other hand, in the circular windings U11, U12, U23, and U24, the solid line portion indicates the layer 3 and the alternate long and short dash line portion indicates the layer 4.

  The circular windings U11 to U24 may be formed of a continuous conductor, or the segment coils may be connected to each other by welding after the segment coils are inserted into the slots. When the segment coil is used, before inserting the segment coil into the slot 237, the coil ends 241 positioned at both ends in the axial direction from the end of the stator core 232 can be formed in advance. The insulation distance can be easily provided. As a result, partial discharge caused by a surge voltage generated by the switching operation of the IGBT 21 can be suppressed, which is effective for insulation.

  In addition, the conductor used for the circular winding may be a flat wire, a round wire, or a conductor with multiple thin wires, but in order to increase the space factor for the purpose of miniaturization and high output, Line is suitable.

  9 and 10 are enlarged views of a part of the U1-phase winding group and the U2-phase winding group shown in FIG. 9 and 10 show about four poles including a jumper wire portion. As shown in FIG. 9B, the stator winding group U1 enters the layer 4 of the slot number 71 from the lead wire and straddles the five slots by the crossing conductor 233b, and then the slot conductor 233a has the slot number of 66. Enter layer 3. Next, layer 4 of slot number 59 is entered from layer 3 of slot number 66 across seven slots.

  Thus, the span of the transition conductor 233b on the coil end side (lower side in the drawing) from which the lead wire is drawn out is the slot pitch Np = 7, and the span of the transition conductor 233b on the opposite coil end side is the slot pitch Np. = 5, the stator winding is wound in a wave winding so that the stator core 232 makes one round until the layer 3 of the slot number 06. The stator winding for approximately one turn so far is the circular winding U11 shown in FIG.

  Next, the stator winding coming out from layer 3 with slot number 06 enters layer 4 with slot number 72 across six slots. From the layer 4 of the slot number 72, it becomes the circular winding U12 shown in FIG. Similarly to the case of the circular winding U11, the amount of the crossover of the crossover conductor 233b is set to the slot pitch Np = 7 on the side where the lead wire is present, and the slot pitch Np = 5 is set on the opposite side. The stator winding is wound by wave winding so that the stator core 232 makes one turn to the layer 3. The stator winding for approximately one turn so far is the circular winding U12.

  Note that the circumferential winding U12 is wound around the circumferential winding U11 with a shift of one slot pitch, so that a phase difference corresponding to an electrical angle corresponding to one slot pitch is generated. In the present embodiment, one slot pitch corresponds to an electrical angle of 30 degrees, and in FIG. 7, the circumferential winding U11 and the circumferential winding U12 are also described as being shifted by 30 degrees.

  Further, the stator winding coming out from the layer 3 of the slot number 07 enters the layer 2 of the slot number 72 (see FIG. 9A) with a jumper wire straddling seven slots. Thereafter, as in the case of the windings U11 and U12, the straddling amount of the crossover conductor 233b is set to the slot pitch Np = 7 on the side where the lead wire is present, and the slot pitch Np = 5 on the opposite side. The stator winding is wound around the stator core 232 from 2 to the layer 1 of slot number 07. The stator winding so far is the circular winding U13 shown in FIG.

  As can be seen from FIG. 9, the circumferential winding U13 is wound around the circumferential winding U12 without being displaced in the circumferential direction, so that no phase difference is generated between the circumferential windings U12 and U13. Also in FIG. 7, the windings U12 and U13 are described so as to have no phase difference.

  Finally, the stator winding coming out of layer 1 of slot number 07 enters layer 2 of slot number 01 across six slots. Thereafter, as in the case of the windings U11, U12, and U13, the amount of straddling the transition conductor 233b is set to the slot pitch Np = 7 on the side where the lead wire is present, and to the slot pitch Np = 5 on the opposite side. The stator winding is wound around the stator core 232 from layer 2 to layer 1 of slot number 08. The stator winding so far is the circular winding U14 shown in FIG.

  Since the circumferential winding U14 is wound around the circumferential winding U13 by shifting by one slot pitch, a phase difference corresponding to an electrical angle of 30 degrees corresponding to one slot pitch is generated. In FIG. 7 as well, the circumferential winding U13 and the circumferential winding U14 are described as being shifted by 30 degrees.

  The stator winding group U2 shown in FIG. 10 is also wound around the wave winding with the same straddling amount as in the case of the stator winding group U1. Circumferential winding U21 is wound from layer 1 of slot number 14 to layer 2 of slot number 07, and circular winding U22 is wound from layer 1 of slot number 13 to layer 2 of slot number 06. Thereafter, the stator winding enters the layer 3 of the slot number 13 from the layer 2 of the slot number 06 through the jumper wire, and is wound as the circumferential winding U23 to the layer 4 of the slot number 06. Thereafter, the winding winding 24 is formed by winding the stator winding from layer 3 of slot number 12 to layer 4 of slot number 05.

  As described above, the stator winding group U1 includes the circular windings U11, U12, U13, and U14, and a voltage obtained by synthesizing the phases is induced in the stator winding group U1. Similarly, in the case of the stator winding group U2, a voltage in which the phases of the circumferential windings U21, U22, U23, U24 are synthesized is induced. As shown in FIG. 7, the stator winding group U1 and the stator winding group U2 are connected in parallel, but there is a phase difference between the voltages induced in the stator winding groups U1 and U2. There is no imbalance such as circulating current flowing even in parallel connection.

  Further, the straddling amount of the crossing conductor 233b is set so that the slot pitch Np = number of slots per pole +1 on one coil end side, and the slot pitch Np = number of slots per pole -1 on the other coil end side. By winding so as to eliminate the phase difference between the windings U12 and U13 and the phase difference between the windings U22 and U23, the arrangement of the slot conductors 233a as shown in FIG. 11 can be realized.

  FIG. 11 is a diagram showing the arrangement of the slot conductors 233a in the stator core 232, and shows slot numbers 71 to 12 in FIGS. The rotation direction of the rotor is from the left to the right in the figure. In the present embodiment, twelve slots 237 are arranged for two poles, that is, an electrical angle of 360 degrees. For example, slot numbers 01 to 12 in FIG. 11 correspond to two poles. Therefore, the number of slots per pole is 6, and the number of slots per pole per phase NSPP is 2 (= 6/3). In each slot 237, four slot conductors 233a of the stator winding 238 are inserted.

  Each slot conductor 233a is shown as a rectangle, and in the rectangle, signs U11 to U24, V, and W indicating U phase, V phase, and W phase, and directions from the lead wire to the neutral point are shown. A black circle mark “●” and a cross mark “×” indicating the opposite direction are shown. Further, the slot conductor 233a located on the innermost side (slot bottom side) of the slot 237 will be referred to as layer 1, and will be referred to as layer 2, layer 3, and layer 4 in order from the outer side (slot opening side). Reference numerals 01 to 12 are slot numbers similar to those shown in FIGS. Note that only the U-phase slot conductor 233a is indicated by reference numerals U11 to U24 representing the circular winding, and the V-phase and W-phase slot conductors 233a are indicated by reference signs V and W indicating the phases.

  In FIG. 11, the eight slot conductors 233a surrounded by the broken line 234 are all U-phase slot conductors 233a. For example, in the case of the slot conductor group 234 shown in the center, the layer 4 with the slot numbers 05 and 06 is the slot conductor 233a of the windings U24 and U23, the layer 3 and the layer 2 with the slot numbers 06 and 07 are the windings U11. , U12 and the slot conductors 233a of the windings U22 and U21 and the layer 1 of the slot numbers 07 and 08 are the slot conductors 233a of the windings U13 and U14.

  In general, when the number of slots per pole is 6, the number of slots per pole is 2, and the number of layers of the slot conductor 233 in the slot 237 is 4, the U phase (V phase, In many cases, a configuration in which the slot conductor 233a of the W phase is also employed is employed. In this case, the interval between the slot conductor group on the right side of the drawing and the slot conductor group on the left side of the drawing is 6 slot pitch.

  On the other hand, as shown in FIG. 12B, the configuration of the present embodiment is such that the two slot conductors 233a of the layer 1 (L1) shown in FIG. And the two slot conductors 233a of the layer 4 (L4) are shifted by one slot pitch in the direction opposite to the rotation direction (left direction in the figure). Therefore, as shown in FIG. 12B, the straddling amount of the cross conductor 233b connecting the slot conductors 233a of the windings U11 of the layers 4 and 3 (L3) is 7 slot pitch, and the layers 4 and 3 ( The straddling amount of the transition conductor 233b connecting the circumferential winding U24 of L3) is 5 slot pitch. In the following, the direction opposite to the rotation direction of the rotor will be referred to as the counter-rotation direction.

  In this case, not only the U phase but also the corresponding slot conductors 233a of the V phase and the W phase are similarly shifted by one slot pitch, so that the same for the U, V, and W phases as shown in FIG. A slot conductor group 234 having a shape is formed. That is, with respect to the rotational direction of the rotor, a slot conductor group consisting of slot conductors 233a with black circles in the U phase, a slot conductor group consisting of slot conductors 233a with cross marks in the W phase, and slots with black circles in the V phase. Slot conductor group composed of conductors 233a, slot conductor group composed of U-phase cross-slot slot conductors 233a, W-phase slot conductor groups composed of black-circle slot conductors 233a, V-phase cross-slot slot conductors 233a A conductor group is arranged.

  In this embodiment, as shown in FIG. 11, (a) the transition conductor 233b has a slot pitch Np = N + 1 (= 7) at one coil end when the number of slots per pole is N (= 6). The slot conductors 233a are connected so as to straddle the slots and at the other coil end so as to straddle the slots at a slot pitch Np = N-1 (= 5). (B) The stator winding is continuous in the circumferential direction of the stator core. A slot conductor group 234 configured by a group of slot conductors 233a of the same phase that are inserted adjacent to a predetermined number of slots Ns (= 4) and arranged adjacent to each other with respect to the slot and the layer, (c) The predetermined slot number Ns is set to Ns = NSPP + NL = 4, where NSPP (= 2) is the number of slots per phase per pole and 2 × NL (NL = 2) is the number of layers.

  Note that the slot conductor 223b is arranged adjacent to the slot and the layer, that is, as shown in FIG. 11, the slot 237 inserted in the same layer is adjacent, and the layer is adjacent in the same slot 237 It means that it is arranged. In this embodiment, the group of slot conductors 233a arranged as described above is referred to as a slot conductor group 234.

  FIG. 13A is an enlarged view of a part of the cross-sectional view shown in FIG. In the core 301 of the rotor core 252, in addition to the air gap 257 formed on both sides of the permanent magnet 254, a groove constituting the magnetic air gap 258 is provided on the surface of the rotor 250. The air gap 257 is provided to reduce cogging torque, and the magnetic air gap 258 is provided to reduce torque pulsation during energization. When viewed from the inner peripheral side of the rotor 250, if the central axis between the left magnets of the permanent magnet 254a is q-axis a and the central axis between the left magnets of the permanent magnet 254b is q-axis b, the magnetic gap 258a is q The magnetic air gap 258b is arranged on the right side with respect to the axis a and is shifted to the left side with respect to the q axis b. Further, the magnetic air gap 258a and the magnetic air gap 258b are arranged symmetrically with respect to the d axis which is the central axis of the magnetic pole.

  On the other hand, FIG. 13B is an enlarged view of a part of the cross-sectional view shown in FIG. In the case of the core 302 of the rotor core 252, magnetic air gaps 258c and 258d are formed instead of the magnetic air gaps 258a and 258b. When viewed from the inner peripheral side of the rotor 250, the magnetic air gap 258c is shifted to the left with respect to the q axis a, and the magnetic air gap 258d is shifted to the right with respect to the q axis b. As can be seen from FIG. 5, the cross-sectional shapes of the core 301 and the core 302 are the same except for the positions of the magnetic air gaps 258a, 258b and 258c, 258d.

  Here, the magnetic air gaps 258a and 258d, 258b and 258c are arranged at positions shifted by 180 degrees in electrical angle. That is, the core 302 can be formed by rotating the core 301 by one magnetic pole. Thereby, the core 301 and the core 302 can be manufactured by the same type | mold, and manufacturing cost can be reduced. Further, the circumferential positions of the holes 253 of the cores 301 and 302 coincide with each other without deviation. As a result, the permanent magnets 254 mounted in the holes 253 penetrate the cores 301 and 302 integrally without being divided in the axial direction. Of course, the plurality of permanent magnets 254 may be provided so as to be stacked in the axial direction of the hole 253.

  When a rotating magnetic field is generated in the stator 230 by the three-phase alternating current, the rotating magnetic field acts on the permanent magnets 254a and 254b of the rotor 250 to generate magnet torque. Further, reluctance torque acts on the rotor 250 in addition to the magnet torque.

  FIG. 14 is a diagram for explaining the reluctance torque. In general, the axis through which the magnetic flux passes through the center of the magnet is called the d-axis, and the axis through which the magnetic flux flows from one pole to another between the poles is called the q-axis. At this time, the iron core portion at the center between the magnets is called an auxiliary salient pole portion 259. Since the magnetic permeability of the permanent magnet 254 provided on the rotor 250 is substantially the same as that of air, the d-axis portion is magnetically concave and the q-axis portion is magnetically convex when viewed from the stator side. It has become. Therefore, the core part of the q-axis part is called a salient pole. The reluctance torque is generated by the difference in the ease of passing the magnetic flux between the d-axis and the q-axis, that is, the salient pole ratio.

  Thus, the rotating electrical machine to which the present invention is applied is a rotating electrical machine that uses both the magnet torque and the auxiliary salient pole reluctance torque. And torque pulsation generate | occur | produces from each of a magnet torque and a reluctance torque. Torque pulsation has a pulsation component that occurs when current is not applied and a pulsation component that is generated when current is applied, and the pulsation component that occurs when current is not applied is generally called cogging torque. When used, torque pulsation is generated by combining cogging torque and pulsation components during energization.

  Most of the methods described as a method for reducing the torque pulsation of the rotating electric machine refer only to the reduction of the cogging torque, and there are many cases where the torque pulsation generated by energization is not described. However, the noise of a rotating electrical machine often occurs at the time of loading, not at no loading. In other words, it is important to reduce the torque pulsation at the time of load reduction in the rotating electric machine, and measures using only the cogging torque are insufficient.

  A method for reducing torque pulsation in the present embodiment will be described.

  First, the no-load characteristic at the time of non-energization will be described. FIG. 15A shows a simulation result of a magnetic flux distribution when no current is passed through the stator winding 238, that is, a magnetic flux distribution by the permanent magnet 254. The region 401 constituted by the permanent magnet 254a is shown in FIG. The two poles of the area | region 402 comprised with the permanent magnet 254b are represented. That is, it is a result of simulating a rotating electrical machine in which the region 401 and the region 402 are alternately arranged in the circumferential direction, and shows an AA cross section. Since the rotating electrical machine of this embodiment has 12 poles, 6 poles are alternately arranged in the circumferential direction. Paying attention to the pole unit, the magnetic gaps 258 a and 258 b are arranged in the auxiliary salient pole part 259 in the region 401, and the auxiliary salient pole part 259 in the region 402 does not have the magnetic gap 258.

  When not energized, the magnetic flux of the permanent magnet 254 short-circuits the magnet end. Therefore, no magnetic flux passes through the q axis. It can also be seen that the magnetic flux hardly passes through the magnetic gaps 258a and 258b provided at positions slightly deviated from the gap 257 at the end of the magnet. The magnetic flux passing through the stator core 232 reaches the teeth 236 through the iron core portion of the permanent magnet 254 on the stator side. For this reason, the magnetic air gaps 258a and 258b hardly affect the magnetic flux at the time of non-energization related to the conging torque, so the magnetic air gaps 258a and 258b do not affect the no-load characteristics such as the cogging torque and the induced voltage. It turns out not to give.

  15B shows the simulation results for only the region 401, FIG. 15C shows the simulation results for only the region 402, FIG. 15B shows only the region 401, and FIG. 15C shows only the region 402 in the circumferential direction. A rotating electric machine in which 12 poles are arranged so that the magnetization direction of the magnet 254 is reversed for each pole is shown. 15B and 15C also have the same magnetic flux distribution as FIG. 15A, and no magnetic flux passes through the q-axis.

  16 and 17 are diagrams for explaining a method of reducing the cogging torque. FIG. 16 is a cross-sectional view showing a part of the rotor 250 and the stator core 232. In FIG. 16, τp is the pole pitch of the permanent magnet 254, and τm is the width angle of the permanent magnet 254. Further, τg is an angle of the permanent magnet 254 and the gap 257 provided on both sides thereof, that is, the width angle of the hole 253 shown in FIG. The cogging torque can be reduced by adjusting the ratios τm / τp and τg / τp of these angles. In this embodiment, τm / τp is called a magnet pole arc degree, and τg / τp is called a magnet hole pole arc degree.

  FIG. 17 is a diagram illustrating the relationship between the ratio of the magnet pole arc degree τm / τp and the conging torque. The results shown in FIG. 17 are obtained when τm = τg, and when the permanent magnet 254 and the gap 257 are concentric with the outer periphery of the rotor 250. When this is a rectangular magnet as in the present embodiment, the optimum value changes slightly, but it goes without saying that the invention is the same. In FIG. 17, the vertical axis represents the amplitude of the conging torque, and the horizontal axis represents the rotation angle represented by the electrical angle of the rotor 250. The magnitude of the pulsation amplitude changes depending on the ratio τm / τp. When τm = τg, the congging torque can be reduced by selecting τm / τp to be about 0.75. Further, the tendency that the cogging torque is not changed by the magnetic air gap 258 shown in FIG. 13A is the same regardless of the value τm / τp of the magnet width and the pole pitch as shown in FIG. That is, the graph of FIG. 17 does not change depending on the position of the magnetic gap 258.

  FIG. 18 shows the waveform of the cogging torque. The horizontal axis represents the rotation angle of the rotor and is indicated by the electrical angle. Line L11 shows the case of the rotor of FIG. 15A in which the regions 401 having the magnetic air gap 258 and the regions 402 having no magnetic air gap 258 are alternately arranged, and the line L12 shows the region 401 having the magnetic air gap 258. 15B shows the case of the rotating electrical machine in FIG. 15B, and the line L13 shows the case of the rotating electrical machine in FIG. 15C in which only the region 402 without the magnetic gap 258 is placed. From the result of FIG. 16A, it can be seen that the presence or absence of the magnetic air gap 258 has little influence on the cogging torque.

  FIG. 19 is a diagram showing an induced voltage waveform, a curve L21 shows an induced voltage waveform of the rotating electrical machine of the present embodiment adopting the slot conductor arrangement shown in FIG. 11, and a curve L22 is described in Patent Document 1 as a comparative example. The induced voltage waveform when the stator structure is adopted is shown. FIG. 20 shows the result of harmonic analysis of each induced voltage waveform of FIG.

  As shown in FIG. 19, it can be seen that the induced voltage waveform indicated by the curve L21 is closer to a sine wave than the induced voltage waveform indicated by the curve L22. Further, as shown in the harmonic analysis result of FIG. 20, it was found that particularly the fifth and seventh harmonic components can be reduced.

  From the results shown in FIGS. 15 to 20, the magnetic air gap 258, which is one of the features of the rotor structure of the present invention, is irrelevant to the cogging torque and the induced voltage. It can be reduced by the ratio of τm / τp, and the harmonic component of the induced voltage can be reduced by the stator structure of the present invention. That is, it is possible to reduce each independently.

  Next, load characteristics during energization will be described.

  The rotating electrical machine of this embodiment is a motor having 6 slots per pole, and the slot conductors 233 of the stator windings 238 provided in the slots 237 of the stator core 232 are arranged as shown in FIG. Therefore, as shown in FIG. 20, the fifth and seventh harmonic components of the induced voltage can be reduced, and the sixth-order torque pulsation specific to the three-phase motor caused by this harmonic component can be reduced. .

  FIG. 21 shows a torque waveform during energization. The horizontal axis represents the rotation angle of the rotor and is indicated by the electrical angle. The line L31 shows the case of the rotor of FIG. 15A in which the regions 401 having the magnetic air gap 258 and the regions 402 having no magnetic air gap 258 are alternately arranged, and the line L32 is the region 401 having the magnetic air gap 258. 15B shows the case of the rotating electrical machine in FIG. 15B, and the line L33 shows the case of the rotating electrical machine in FIG. 15C in which only the region 402 without the magnetic gap 258 is placed.

  As can be seen from FIG. 21, in the rotating electrical machine of the present embodiment, the 12th-order torque pulsation component, that is, the electrical angle component of 30 deg period is dominant, and the 6th-order component is hardly present. Further, it can be seen that the torque pulsation waveform is changed in both L31 and L32 with respect to the torque pulsation L33 in the case where the magnetic air gap 258 is not formed, that is, only in the region 402. This indicates that the magnetic flux during energization is affected by the magnetic gap 258. Furthermore, the torque pulsation L32 of the rotating electrical machine only in the region 401 and the torque pulsation L33 of the rotating electrical machine only in the region 402 are almost opposite in phase. As shown in FIG. 15A, the rotating electrical machine of the present embodiment has a configuration in which regions 401 and regions 402 are alternately arranged, and the total torque pulsation received by the entire rotor as shown by torque pulsation L31. Is the average value of torque pulsation L32 and torque pulsation L33.

  Thus, in the present embodiment, the torque pulsation during energization can be reduced by providing the magnetic gaps 258a and 258b as described above. In order to obtain such an effect, it is preferable to set the width angle (circumferential direction angle) of the grooves constituting the magnetic air gap 258 within a range of ¼ to ½ of the pitch angle of the teeth 236. The same effect can be obtained even if the magnetic air gap is arranged symmetrically with respect to the q axis passing through the magnetic pole center and asymmetric with respect to the d axis passing through the salient pole center. Two or more kinds of magnetic gaps 258 formed in the auxiliary salient pole portion 259 may be used. Thereby, the freedom degree of torque pulsation reduction increases, and pulsation reduction can be performed in more detail.

  Further, it has a feature that the torque does not decrease compared to the case where no magnetic gap is provided. Conventionally, in the case of a structure called skew for reducing torque pulsation, there has been a drawback that the torque is lowered by the skew and hinders downsizing. However, this embodiment has an advantage that not only the torque pulsation during energization can be reduced independently of the cogging torque, but also the torque itself does not decrease. This is because the torque pulsation in the case of the original grooveless rotor is dominated by the twelfth order component, which is also effective because the slot conductor 233 is arranged as shown in FIG.

  FIG. 22 shows the result of harmonic analysis of the torque waveform during energization. The line L41 shows the arrangement of the slot conductor 233 in FIG. 12A, and the rotor has a magnetic gap 258 as shown in FIG. 15C. FIG. 12B shows the arrangement of the slot conductor 233 in this embodiment, and the rotor is provided with a magnetic air gap 258 as shown in FIG. 15C. FIG. 12B shows the arrangement of the slot conductor 233 in this embodiment, and the rotor has a structure as shown in FIG. 15A of this embodiment. It is a result of a rotating electrical machine.

  As shown in the harmonic analysis result of FIG. 22, it can be seen that the line L42 has a reduced sixth-order component, which is a component of the electrical angle 60 deg period, compared to the line L41. This indicates that the arrangement of the slot conductor 233 is reduced by making the arrangement shown in FIG. Also. It can be seen that the line 43 has a reduced 12th-order component, which is a component having an electrical angle of 30 deg, compared to the line L42. This indicates that the rotor is reduced by adopting the structure as shown in FIG. 15A, which is the present embodiment. That is, it can be reduced independently by the harmonic order of the torque ripple.

  As described above, the torque ripple can be reduced in the present embodiment, but when the rotating electrical machine generates torque, an electromagnetic excitation force that vibrates the stator core 232 in an annular shape is generated, and this circular vibration causes noise. It may be a cause.

  FIG. 23 shows the vibration mode of the annular zero-order component of the stator core 232. The thin line indicates the original shape of the stator core 232. This vibration mode causes noise by resonating with an electromagnetic excitation force having an annular zero-order component, but the magnitude of the annular zero-order electromagnetic excitation force is equivalent to the magnitude of the torque ripple. In this embodiment, the torque ripple can be reduced in the same manner as the torque ripple since the electromagnetic excitation force of the zeroth-order ring can be reduced by reducing the torque ripple.

  FIG. 24 shows the vibration mode of the annular sixth-order component of the stator core 232. The thin line indicates the original shape of the stator core 232. This vibration mode also causes noise by resonating with an electromagnetic excitation force having an annular sixth-order component, but in this embodiment, as shown in FIG. Since the magnetic gap 258 is provided and there is a magnetic imbalance for each pole, an excitation force having an annular order of 1/2 the number of poles is generated for each of the cores 301 and 302 shown in FIG. However, since the magnetic air gaps 258 between the core 301 and the core 302 are disposed at positions shifted by one pitch of the magnetic poles, the electromagnetic excitation force is canceled in the axial direction and resonates with the annular sixth-order vibration mode. There is nothing.

  FIG. 25 shows a vibration mode in which the stator core 232 has an annular sixth-order component and the phase is inverted at both ends in the axial direction of the stator. The thin line indicates the original shape of the stator core 232. Since the electromagnetic excitation force generated by the core 301 and the core 302 is inverted in phase as described above, if the two types of cores, the core 301 and the core 302, constitute a rotor core in two stages, they will resonate. However, by configuring in three stages as in the present embodiment, the electromagnetic excitation force does not resonate with this vibration mode. Of course, if two or more types of cores are configured in three or more stages, the same effect as this embodiment can be obtained.

[Second Embodiment]
FIG. 26 and FIG. 27 are diagrams showing a second embodiment of the present invention, in which the number of slots per phase per pole NSPP is 2, and the number of layers of the slot conductor 233a inserted into one slot 237 is 2. The case where this invention is applied to a stator is shown. The rotor has the same configuration as in the first embodiment. FIG. 26 is a diagram showing the detailed connection of the U-phase winding of the stator winding, where (a) shows the U1-phase winding group and (b) shows the U2-phase winding group. FIG. 27 is a diagram showing the arrangement of the slot conductors 233a in the stator core 232. As shown in FIG.

  As shown in FIG. 26, the circular winding U11 of the U1-phase winding group enters the layer 2 of the slot number 72 from the lead wire, enters the layer 1 of the slot number 67 after straddling 5 slots by the crossing conductor 233b. Next, the winding that exits layer 1 of slot number 67 enters layer 2 of slot number 60 across seven slots. Thereafter, the winding is wave-wound while alternately repeating the straddle of 5 slots and the stride of 7 slots, and enters the layer 1 of the slot number 07 after substantially making a round of the stator core 232. Up to this point is the circular winding U11.

  The winding that exits layer 1 of slot number 07 enters layer 2 of slot number 01 after straddling 6 slots. From here, the winding winding U12 is wound in the same manner as in the winding winding U11, with the five-slot bridge and the seven-slot bridge being alternately repeated. Enter layer 1 of 08.

  The windings of the U2-phase winding group are also wound by wave winding as in the case of the U1-phase winding group. The winding wound from layer 1 of slot number 14 to layer 2 of slot number 07 is the circular winding U21, and the winding from layer 1 of slot number 13 to layer 2 of slot number 06 is the circular winding. U22.

  FIG. 27 shows the arrangement of the slot conductors 233a in the portions of the slot numbers 01 to 12 and the slot numbers 71 and 72, and the 12-slot pitch from the slot number 01 to the slot number 12 corresponds to two poles. 27 and FIG. 11 are compared, the arrangement of the U, V, and W phase slot conductors 233a shown in FIG. 27 is the same as the arrangement of the layer 1 and 2 slot conductors 233a shown in FIG. In the case of the present embodiment, four slot conductors 233a surrounded by a broken line constitute one slot conductor group 234.

The slot conductor group 234 of the present embodiment also satisfies the same conditions as the slot conductor group 234 (see FIG. 11) of the first embodiment described above. That is, (a) when the number of slots per pole is N (= 6), the crossover conductor 233b straddles the slot with a slot pitch Np = N + 1 = 7 at one coil end, and the slot pitch Np = at the other coil end. The slot conductors 233a are connected so as to straddle the slots with N-1 = 5, and (b) the stator windings are arranged in slots of a predetermined number of slots Ns (= 3) arranged continuously in the circumferential direction of the stator core. A slot conductor group 234 composed of a group of slot conductors 223b of the same phase disposed adjacent to each other with respect to the slot and the layer, and (c) the predetermined slot number Ns is defined as NSPP ( = 2) When the number of layers is 2 × NL (NL = 1), Ns = NSPP + NL = 3.

  Therefore, similarly to the first embodiment, torque ripple can be reduced, and noise reduction of a low-noise rotating electrical machine can be achieved.

[Third Embodiment]
FIG. 28 and FIG. 29 are diagrams showing a third embodiment of the present invention, where the number of slots per phase per phase NSPP is 3, and the number of layers of the slot conductor 233a inserted into one slot 237 is 4. The case where this invention is applied to a stator is shown. The rotor has the same configuration as in the first embodiment. FIG. 28 shows a part of the detailed connection of the U-phase winding, in which (a) shows the U1-phase winding group and (b) shows the U2-phase winding group. FIG. 19 is a diagram showing the arrangement of the slot conductors 233a in the stator core 232.

  As shown in FIG. 28, when the number of slots per phase per pole NSPP is 3 and the number of layers 2 × NL of the slot conductor 233a inserted into one slot 237 is 4, the number of slots of the stator core 232 is 108. The number of the circumferential windings constituting the U1-phase winding group and the U2-phase winding group is 6, respectively. Further, the straddling amount in each winding is also 5 slot pitch and 7 slot pitch.

  In the U1-phase winding group shown in FIG. 28A, the winding from the layer 4 of the slot number 105 to the layer 3 of the slot number 07 is the circular winding U11, and the layer 4 of the slot number 106 to the slot number 08 is wound. The winding up to layer 3 is the circular winding U12, and the winding from layer 4 of slot number 107 to layer 3 of slot number 09 is the circular winding U13. The winding that exits layer 3 of slot number 09 enters layer 2 of slot number 106 via a jumper wire. The winding from layer 2 of slot number 106 to layer 1 of slot number 08 is the circular winding U14, and the winding from layer 2 of slot number 107 to layer 1 of the slot number 09 is circular winding U15. The winding from layer 2 of slot number 108 to layer 1 of slot number 10 is a circular winding U16.

  In the U2-phase winding group shown in FIG. 28B, the winding from the layer 1 of slot number 19 to the layer 2 of slot number 09 is the circular winding U21, and the winding of layer number 1 from slot 1 to the slot number 08 is turned on. The winding up to layer 2 is the circular winding U22, and the winding from layer 1 of slot number 17 to layer 2 of slot number 07 is the circular winding U13. The winding that exits layer 2 of slot number 07 enters layer 3 of slot number 18 via a jumper wire. The winding from layer 3 of slot number 18 to layer 4 of slot number 08 is the circular winding U24, and the winding from layer 3 of slot number 17 to layer 4 of the slot number 07 is circular winding U25. The winding from layer 3 of slot number 18 to layer 4 of slot number 06 is a circular winding U26.

  FIG. 29 shows the arrangement of the slot conductors 233a in the portions corresponding to the slot numbers 01 to 18. In the case of this embodiment, the 18 slot pitch from the slot number 01 to the slot number 18 corresponds to two poles. . As can be seen from FIG. 28, the windings U14 to U16 and the windings U21 to U23 are alternately inserted into the layer 1 and the layer 2 of the slot 237, while the windings U11 to U13 and The windings U24 to U26 are alternately inserted into the layer 3 and the layer 4 of the slot 237. Then, twelve slot conductors 233a surrounded by a broken line in FIG. 29 constitute a group and constitute one slot conductor group 1234. These twelve slot conductors 233a are slot conductors 233a included in twelve circumferential windings U111 to U16 and U21 to U26 of the same phase.

  The V-phase and W-phase slot conductors 233a are the same as in the U-phase, and 12 slot conductors 233a of the same phase are grouped to form one slot conductor group. As in the case of the first embodiment, these slot conductor groups are, in order with respect to the rotational direction of the rotor, a slot conductor group consisting of slot conductors 233a of black circles in the U phase and cross marks in the W phase. Slot conductor group consisting of slot conductors 233a, slot conductor group consisting of slot conductors 233a marked with black circles in the V phase, slot conductor group consisting of slot conductors 233a marked in the U phase, and slot conductors 233a marked with black circles in the W phase. A slot conductor group consisting of the slot conductor group 233a and the slot conductor 233a cross-marked in the V phase is arranged.

  As can be seen from FIG. 29, the slot conductor group 1234 of the present embodiment also satisfies the same conditions as the slot conductor group 234 (see FIG. 11) of the first embodiment described above. That is, (a) when the number of slots per pole is N (= 9), the crossover conductor 233b straddles the slots with a slot pitch Np = N + 1 = 10 at one coil end, and the slot pitch Np = at the other coil end. The slot conductors 233a are connected so as to straddle the slots at N-1 = 8, and (b) the stator windings are arranged in slots of a predetermined number of slots Ns (= 5) arranged continuously in the circumferential direction of the stator core. A slot conductor group 234 composed of a group of slot conductors 223b of the same phase disposed adjacent to each other with respect to the slot and the layer, and (c) the predetermined slot number Ns is defined as NSPP ( = 3) When the number of layers is 2 × NL (NL = 2), Ns = NSPP + NL = 5 is set.

  Therefore, as in the first and second embodiments, torque ripple can be reduced, and the noise of a low-noise rotating electrical machine can be reduced.

  By the way, when the number of slots NSPP per pole increases, the order of high frequency components that can be eliminated by shifting the pitch by one slot as shown in FIG. 12 changes. For example, when NSPP = 2, one slot pitch corresponds to 30 degrees in electrical angle. Since 30 degrees is a half cycle of the sixth-order component, as shown in FIG. 20, the induced voltages of the fifth-order component and the seventh-order component close to the sixth order can be reduced. On the other hand, if NSPP is further increased as in the present embodiment, the 1-slot pitch is reduced, so that higher-order harmonic components can be further reduced. Further, by reducing the width of the magnetic air gap 258 provided in the rotor core 252, it is possible to further reduce higher-order torque ripple harmonic components, and to provide a rotating electrical machine that is more excellent in quietness.

  As shown in FIGS. 1 and 2, the rotating electrical machine includes the above-described rotating electrical machine, a battery that supplies DC power, and a converter that converts the DC power of the battery into AC power and supplies the AC power to the rotating electrical machine. In the vehicle characterized by using this torque as the driving force, a quiet vehicle with reduced noise can be provided.

  The 12-pole magnet motor has been described above as an example. Further, the present invention is not limited to a vehicle motor, but can be applied to motors used for various purposes. Furthermore, the present invention is not limited to a motor, and can be applied to various rotating electrical machines such as a generator. In addition, the present invention is not limited to the above-described embodiment as long as the characteristics of the present invention are not impaired.

100 Vehicle 120 Engine 180 Battery 200, 202 Rotating electrical machine 230 Stator 232 Stator core 233a Slot conductor 233b Transition conductors 234, 234A to 234C, 1234A to 1234C, 2234A to 2234C Slot conductor groups 235a, 235b, 1235a, 1235b Small slot conductors Group 237 Slot 238 Stator winding 241 Coil end 250 Rotor 252 Rotor core 254 Permanent magnet 257 Air gap 258 Magnetic air gap 259 Auxiliary salient pole part 600 Power converters U11 to U14, U21 to U24, V11 to V14, V21 to V24, W11 to W14, W21 to W24 Circumferential winding

Claims (11)

A stator core formed with a plurality of slots;
A coil conductor is formed by connecting a slot conductor that is inserted into each slot of the stator core to constitute one of a plurality of layers and the same side ends of slot conductors that are inserted into different slots. A plurality of phase stator windings having a plurality of wave windings composed of crossover conductors, and
A plurality of magnets, a plurality of magnetic auxiliary salient poles formed between poles of the magnets, and a first provided on a side surface of the magnets are provided to be rotatable with respect to the stator core via a gap. A rotor having a magnetic air gap of
When the number of slots per pole is N, the crossover conductor spans the slot at the slot pitch Np = N + 1 at one coil end and the slot at the slot pitch Np = N−1 at the other coil end. Connect between conductors,
The stator winding has a plurality of a group of slot conductor groups composed of a plurality of slot conductors of the same phase,
The plurality of slot conductors of the slot conductor group are inserted so that slots and layers are adjacent to each other in a predetermined number Ns of slots arranged continuously in the circumferential direction of the stator core,
The predetermined number Ns is set to Ns = NSPP + NL when the number of slots per phase per pole is NSPP and the number of layers is 2 × NL,
A second magnetic air gap is formed in the magnetic auxiliary salient pole portion of the rotor symmetrically with respect to the d-axis and asymmetrically with respect to the q-axis,
The second magnetic gap is provided on the right side or the left side with respect to the q axis so that torque pulsation during energization is canceled in a cross section perpendicular to the axial direction.
When the pole pitch of the magnet is τp, and the angle of the magnet and the first magnetic gap provided on the side surface is τg,
A rotating electric machine having a magnet hole pole arc degree τg / τp of 0.5 to 0.9. The rotating electrical machine according to claim 1,
The rotating electrical machine in which the magnet hole pole arc degree τg / τp is 0.7 to 0.8. The rotating electrical machine according to claim 1,
A rotating electrical machine in which the second magnetic gap is a groove provided on an outer periphery of the rotor core. The rotating electrical machine according to any one of claims 1 to 2,
The rotating electrical machine wherein the second magnetic air gap is provided independently of the first magnetic air gap. The rotating electrical machine according to claim 1,
The rotary electric machine, wherein the second magnetic gap is a recess formed on a surface of the rotary core. In the rotating electrical machine according to claim 1,
The rotating electrical machine, wherein the slot conductor is a flat wire. In the rotating electrical machine according to claim 1,
The stator winding has a plurality of Y connections, and there is no phase difference in the voltage induced in each phase winding of each Y connection. In the rotating electrical machine according to claim 1,
The rotor is a rotating electrical machine having a rotor core on which electromagnetic steel plates each having a hole or notch forming the second magnetic gap are stacked. The rotating electrical machine according to claim 8,
The rotor core is divided into a plurality of axially divided core groups each having the magnet, the magnetic auxiliary salient pole portion, the first magnetic air gap, and the second magnetic air gap, and the magnet and the The circumferential position of the first magnetic gap is constant regardless of the axially divided core group, and at least two types of axially divided core groups having different circumferential positions of the second magnetic gap are 3 A rotating electrical machine consisting of two or more. The rotating electrical machine according to any one of claims 1 to 9,
6. A rotating electrical machine characterized in that a torque ripple of a sixth-order component with respect to an electrical angle of 360 degrees is reduced with the configuration of the stator winding, and a torque ripple of a twelfth-order component is reduced by the magnetoresistance change unit. A rotating electrical machine according to any one of claims 1 to 10,
A battery for supplying DC power;
A conversion device that converts the DC power of the battery into AC power and supplies it to the rotating electrical machine,
A vehicle using the torque of the rotating electric machine as a driving force.

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