JP2014030293A - Rotor of rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotor that facilitates flow of main magnetic flux into rotor salient poles, and thus increases rotor torque, with a configuration in which permanent magnets are embedded in the rotor salient poles.SOLUTION: A rotor 14 includes: a rotor core 22 that has rotor salient poles 28n and 28s provided at a plurality of positions in a circumferential direction; permanents magnets 26 that are embedded in the respective rotor salient poles 28n and 28s and that are magnetized in a rotor radial direction; and magnetic flux flow restricting sections 33 that are provided circumferentially adjacent to the respective permanent magnets 26 inside the respective rotor salient poles 28n and 28s and that have lower magnetic permeability than the rotor salient poles 28n and 28s.

Description

  The present invention relates to a rotor of a rotating electrical machine, and more particularly to a rotor in which a permanent magnet is embedded in a rotor salient pole.

  Conventionally, as described in Patent Document 1, a rotating electrical machine is known in which a rotor winding is wound around a plurality of rotor salient poles of a rotor, and each rotor winding is short-circuited with a polarity selected by a diode. ing. In this rotor, the current flowing through each rotor winding is rectified by the diode, and the direction of magnetization of the rotor salient poles adjacent in the circumferential direction of the rotor is reversed. In a stator of a rotating electrical machine, a plurality of stator windings are wound around a plurality of stator salient poles in a concentrated manner. A rotating magnetic field is generated in the stator by passing an alternating current through the stator winding. Then, an induction current is generated in the rotor winding by a spatial harmonic that is a harmonic component included in the rotating magnetic field generated in the stator. As a result, in the plurality of rotor salient poles, N poles and S poles are alternately formed in the circumferential direction of the rotor, and the rotor salient poles interact with the rotating magnetic field to generate torque in the rotor.

  Patent Document 1 includes a permanent magnet disposed on rotor salient poles at a plurality of locations in the circumferential direction of the rotor, and a rotor winding wound around each salient pole. A structure in which the magnetization direction of the inner permanent magnet is made to coincide is also described.

  Patent Document 2 describes a rotating electrical machine in which a rotor winding is wound around a plurality of rotor salient poles and permanent magnets are arranged at a plurality of locations on the radially inner side of the rotor core. The rotor windings are fed by non-contact feeding using feeding coils arranged on the stator side and the rotor side, respectively, and a magnetic field along the magnetic circuit generated by the current of the rotor windings during feeding is formed by a permanent magnet. Yes.

JP 2011-41433 A JP 2010-166787 A

  In the case of the configuration described in Patent Document 1, the magnetic flux of the permanent magnet may interfere with the flow of the main magnetic flux generated by the stator in the rotor salient pole, and there is room for improvement in terms of increasing the rotor torque.

  An object of the present invention is to increase a rotor torque by facilitating the flow of a main magnetic flux to a rotor salient pole with a configuration in which a permanent magnet is embedded in the rotor salient pole in a rotor of a rotating electrical machine.

  A rotor of a rotating electrical machine according to the present invention is a rotor of a rotating electrical machine including a rotor core including rotor salient poles provided at a plurality of locations in the circumferential direction, embedded in each of the rotor salient poles, and the magnetization direction is the rotor radial direction Each of the rotor salient poles and a magnetic flux flow restricting portion that is provided adjacent to the permanent magnet in the circumferential direction and has a lower magnetic permeability than the rotor salient poles. To do.

  In the rotor of the rotating electrical machine according to the present invention, preferably, the magnetic flux flow restriction portion is embedded in the notch portion and a notch portion provided in each rotor salient pole adjacent to the permanent magnet in the circumferential direction. It is comprised from a nonmagnetic member.

  In the rotor of the rotating electrical machine according to the present invention, preferably, the magnetic flux flow restricting portion is projected outward from the outer end face of the permanent magnet in the rotor radial direction.

  In the rotor of the rotating electrical machine according to the present invention, preferably, the permanent magnets embedded in the rotor salient poles adjacent in the circumferential direction have different magnetization directions, and the rotor windings wound around the rotor salient poles. And a rectifying unit that rectifies the induced current generated in each rotor winding in one direction and matches the magnetization direction generated in the plurality of rotor salient poles with the magnetization direction of the permanent magnet.

  According to the rotor of the rotating electrical machine of the present invention, the permanent magnet is embedded in the rotor salient pole, and the magnetic flux flow limiting portion having a lower permeability than the rotor salient pole is provided adjacent to the permanent magnet in the circumferential direction. The flow of the main magnetic flux generated in the rotor salient pole is less likely to be hindered by the magnetic flux of the permanent magnet. For this reason, the rotor torque can be increased by effectively using the magnetic attractive force between the stator and the rotor.

It is a schematic block diagram of the rotary electric machine drive system which drives the rotary electric machine containing the rotor of embodiment of this invention. It is the A section enlarged view of FIG. In the rotating electrical machine drive system of FIG. 1, when the stator salient pole (a) having a different polarity is opposed to the salient pole of the stator and the rotor salient pole having the same polarity is opposed to the salient pole of the stator It is a figure which shows the stator current (b). It is a figure which shows a mode that the rotor salient pole for N pole formation opposes the salient pole of the S pole of a stator, and a rotor rotates. It is a figure which shows a mode that the rotor salient pole for S pole formation opposes the salient pole of the N pole of a stator, and a rotor rotates. It is a figure which shows a mode that the rotor salient pole for S pole formation opposes the salient pole of the S pole of a stator, and a rotor rotates. It is a figure which shows a mode that the rotor salient pole for N pole formation opposes the salient pole of N pole of a stator, and a rotor rotates. In the rotor of FIG. 1, it is a schematic diagram which shows a mode that the magnetic flux of a permanent magnet loops in a rotor salient pole. In the rotor of the other example of embodiment of this invention, it is a schematic diagram which shows a mode that the magnetic flux of a permanent magnet loops in a rotor salient pole.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the stator core and the rotor core are described as being formed by laminating electromagnetic steel plates, but this is an example, and a plate material other than the electromagnetic steel plates may be laminated. Other stator cores and rotor cores may be used. For example, an integrated core obtained by processing a steel material or a core formed by compacting magnetic powder may be used. Moreover, each core is good also as a split-type core formed by connecting the some element divided | segmented into the circumferential direction cyclically | annularly.

  The number of salient poles of the stator and the number of salient poles of the rotor described below are examples for explanation and can be appropriately changed. In the following description, like reference numerals denote like elements in all drawings.

  FIG. 1 is a schematic configuration diagram of a rotating electrical machine drive system 10 that drives a rotating electrical machine 11 including a rotor 14 according to an embodiment of the present invention.

  The rotating electrical machine drive system 10 includes a rotating electrical machine 11 and a drive unit 13. The rotating electrical machine drive system 10 is mounted on an electric vehicle such as a hybrid vehicle or an electric vehicle, uses the rotating electrical machine 11 as a motor, and is used to drive a wheel (not shown) by the rotating electrical machine 11. The rotating electrical machine 11 may be used as a generator.

  The rotating electrical machine 11 includes a stator 12 fixed to a casing (not shown), and a rotor 14 disposed to face the stator 12 in the radial direction.

  The stator 12 includes a stator core 16 and three-phase stator windings 18u, 18v, and 18w that are a plurality of phases wound around the stator core 16, that is, a u-phase, a v-phase, and a w-phase. The stator core 16 is made of a magnetic material such as a laminate of metal plates such as electromagnetic steel plates. The stator core 16 includes a plurality of salient poles 19 projecting radially inward toward the rotor 14 at a plurality of equally spaced positions in the circumferential direction, and slots 20 formed between the salient poles 19. . The “radial direction” refers to a radial direction orthogonal to the rotation center axis of the rotor 14. In addition, the “circumferential direction” refers to the rotor circumferential direction around the rotation center axis of the rotor 14. Further, the “axial direction” refers to the axial direction of the rotor 14.

  The stator windings 18u, 18v, and 18w are wound around the salient poles 19 through the slots 20 in a concentrated manner. When a plurality of alternating currents flow through the stator windings 18 u, 18 v, 18 w, the salient poles 19 are magnetized and a rotating magnetic field is generated in the stator 12. In FIG. 1, the symbols u, v, and w representing the phases of the stator current flowing in the stator windings 18 u, 18 v, and 18 w, the v phase, and the w phase are shown on the outer peripheral side of the stator 12.

  Note that the stator winding may be a toroidal winding in which a plurality of phases of the stator winding are wound at a plurality of locations in the circumferential direction of the annular portion of the stator core 16.

  The rotor 14 is disposed opposite to the stator 12 in the radial direction with a predetermined gap, and is rotatable with respect to the stator 12. A rotating shaft 21 supported by a bearing of a casing of the rotating electrical machine 11 is inserted and fixed in the central shaft hole of the rotor 14. The rotor 14 includes a rotor core 22 and rotor windings 24 n and 24 s wound around the rotor core 22. The rotor core 22 is formed of a magnetic material such as a laminate of metal plates such as electromagnetic steel plates, and includes rotor salient poles 28n and 28s that are magnetic pole portions provided at a plurality of locations at equal intervals in the circumferential direction on the outer peripheral side.

  The rotor windings 24n and 24s are composed of a rotor winding 24n wound around every other rotor salient pole 28n in the circumferential direction of the rotor 14 and another every other rotor projection adjacent to the rotor salient pole 28n. The rotor winding 24s is wound around the pole 28s by concentrated winding. A first diode 30 is connected so as to short-circuit each rotor winding 24n in one direction, and a second diode 32 is connected so as to short-circuit each rotor winding 24s in the other direction. The first diode 30 and the second diode 32 are rectifiers.

  In this configuration, when an induced current flows through the rotor windings 24n and 24s as will be described later, the current is rectified in one direction by the diodes 30 and 32 connected thereto, so that the rotor salient poles 28n and 28s are desired. Magnetize to the polarity of. The rotor salient pole 28n is for forming an N pole at the tip, and the rotor salient pole 28s is for forming an S pole at the tip. Since the rotor salient poles 28 n and 28 s are alternately arranged in the circumferential direction, the N pole and the S pole are alternately arranged in the circumferential direction of the rotor 14.

  The permanent magnet 26 is a plate having a rectangular cross section made of ferrite or the like, inserted into a magnet hole formed in the axial direction of each rotor salient pole 28n, 28s, and embedded and fixed in each rotor salient pole 28n, 28s. The The magnetization direction of each permanent magnet 26 faces the rotor radial direction. In FIG. 1 and FIG. 2 to be described later, the tips of the rotor salient poles 28n and 28s are denoted by N and S, which are magnetic poles disposed on the radially outer side of the permanent magnets 26, and the rotor. The magnetic poles generated at the tips of the rotor salient poles 28n and 28s by the induced current generated in the windings 24n and 24s are shown. The permanent magnets 26 embedded in the rotor salient poles 28n and 28s adjacent to each other in the circumferential direction have different magnetization directions. The magnetization direction generated in the plurality of rotor salient poles 28n and 28s by the induced current generated in each rotor winding 24n and 24s is made to coincide with the magnetization direction of the permanent magnet 26.

  The magnetic flux flow restricting portion 33 is provided inside the rotor salient poles 28n and 28s so as to be adjacent to both sides of the permanent magnet 26 in the circumferential direction, and has a magnetic permeability lower than that of the rotor salient poles 28n and 28s. is there. FIG. 2 is an enlarged view of part A in FIG. The magnetic flux flow restricting portion 33 includes a notch portion 34 provided adjacent to both sides in the circumferential direction of each rotor salient pole 28n, and a resin member 36 that is a nonmagnetic member embedded in each notch portion 34 in a filled state. Composed. The nonmagnetic member may be a nonmagnetic metal other than resin. In some cases, the magnetic flux flow restricting portion may be formed by using the notch 34 so that the inner side becomes a gap without using a nonmagnetic member.

  Each notch 34 has a trapezoidal cross-sectional shape. That is, both side surfaces in the circumferential direction of each notch 34 are parallel to the circumferential side surface of the permanent magnet 26. Further, the radially outer surface P which is the upper side surface of each notch 34 is tapered, and is inclined so as to approach the circumferential side surface of each rotor salient pole 28n toward the radially outer side which is the upper side of FIG. I am letting. The radially outer surface P of each notch 34 protrudes outward in the radial direction, which is the upper side of FIG. 2, than the radially outer surface Q, which is the upper end surface of the permanent magnet 26 in FIG. 2. For this reason, the magnetic flux flow restricting portion 33 protrudes outside the outer surface Q of the permanent magnet 26. 2 is formed in a direction orthogonal to the radial direction, and is located on the radially outer side, which is the upper side in FIG. 2, with respect to the radial inner side surface R of the permanent magnet 26. I am letting. Although the rotor salient pole 28n for forming the N pole has been described with reference to FIG. 2, the same applies to the magnetic flux flow restricting portion 33 of the rotor salient pole 28s for forming the S pole.

  Returning to FIG. 1, the rotating electrical machine 11 is driven by the drive unit 13 of the rotating electrical machine drive system 10. Drive unit 13 includes a power storage device 40, an inverter 42, and a control device 44. The power storage device 40 is provided as a direct current power source and is chargeable / dischargeable, and is constituted by, for example, a secondary battery. The power storage device 40 may be a capacitor. Inverter 42 is connected to power storage device 40 and converts a direct current from power storage device 40 into a three-phase alternating current of u phase, v phase, and w phase. A booster device may be provided between the inverter 42 and the power storage device 40.

  The control device 44 includes a microcomputer having a CPU, a memory, and the like. For example, when the rotating electrical machine 11 is used as a vehicle drive motor, the control device 44 rotates according to an acceleration command signal input from an accelerator pedal sensor (not shown) of the vehicle. A torque target of the electric machine 11 is calculated. The control device 44 controls the switching of the switching element of the inverter 42 according to the calculated torque target, and drives the inverter 42. The control device 44 may be configured by a plurality of control devices divided for each function.

  The control device 44 includes a pulse superimposing unit 46 that superimposes a pulse current on the stator current flowing through the stator windings 18u, 18v, and 18w. The pulse superimposing unit 46 has a function of switching whether or not the pulse current is superimposed so that the pulse current is superimposed on the stator current of a predetermined phase only at a necessary timing. This will be described with reference to FIG. As a case where the salient pole 19 of the stator 12 and the rotor salient poles 28n and 28s face each other, the rotor salient poles 28n and 28s that form a polarity different from the salient pole 19 face the salient pole 19 formed on the S pole or the N pole. There are two cases: a case where the rotor salient poles 28n and 28s having the same polarity as the salient pole 19 are opposed to the salient pole 19. In FIG. 3, the stator current of a predetermined phase in each of the two cases is shown as an absolute value. The stator current of the predetermined phase is a stator current of a phase different from the phase of the stator winding 18u (or any one of 18v and 18w) wound around the salient pole 19 facing the rotor salient poles 28n and 28s. For example, when the rotor salient poles 28n and 28s face the salient pole 19 around which the stator winding 18u is wound, the stator current of the v phase or w phase or both the v and w phases is the stator current of a predetermined phase. A pulse current is superimposed on the stator current of the predetermined phase to generate a leakage magnetic flux, which will be described later, which fluctuates greatly in the slot 48 in which the rotor windings 24n and 24s are arranged.

  FIG. 3A shows a case where the rotor salient poles 28n and 28s that form a polarity different from that of the salient pole 19 are opposed to the salient pole 19 formed on the S pole or the N pole. In this case, the pulse superimposing unit 46 applies a pulse current to the stator current of a predetermined phase from a time ta at which there is a predetermined phase difference immediately before the rotor salient poles 28n and 28s face the salient pole 19 to an opposing time t0. Inductive current is generated in the rotor windings 24n and 24s by superimposing them. The reason why the induced current is generated by superimposing the pulse current on the stator current will be described later. The pulse current may have other shapes such as a rectangular shape in addition to the triangular wave shape as shown in FIG. A plurality of pulse currents may be continuously superimposed. In FIG. 3, in the one-phase stator current, the portion where the pulse current is not superimposed is shown in a straight line, but this is shown by extending a very short time in the horizontal direction, and actually changes in a sine wave shape. doing.

  FIG. 3B shows a case where the rotor salient poles 28s and 28n having the same polarity as the salient pole 19 are opposed to the salient pole 19 formed on the S pole or the N pole. In this case, the pulse superimposing unit 46 does not superimpose the pulse current on the stator current of the predetermined phase at the facing time t0 between the salient pole 19 and the rotor salient poles 28s and 28n, the facing time within a predetermined range including immediately before and immediately after facing. . In this case, no induced current is generated in the rotor windings 24s and 24n wound around the rotor salient poles 28s and 28n. The reason why the induced current is not generated by not superimposing the pulse current on the stator current will be described later.

  Next, operation | movement of the rotary electric machine 11 is demonstrated using FIG. 1 and FIGS. In particular, it will be described that the rotating electrical machine 11 is operated by reluctance torque, magnet torque, and winding magnetomotive force torque that is torque generated by induced current. A rotating magnetic field is formed in the stator 12 by a three-phase alternating current flowing through the three-phase stator windings 18u, 18v, and 18w shown in FIG. 1, and this rotating magnetic field is higher than the fundamental wave component and the fundamental wave. It includes harmonic components such as spatial second order called spatial harmonics of the order. When the fundamental wave component of the rotating magnetic field acts on the rotor 14, the rotor salient poles 28 n and 28 s are attracted to the salient pole 19 of the stator 12 so that the magnetic resistance of the rotor 14 decreases accordingly. As a result, reluctance torque acts on the rotor 14.

  In addition, since the plurality of permanent magnets 26 are provided on the plurality of rotor salient poles 28n and 28s so that the magnetization directions are alternately reversed in the circumferential direction, the magnetic component between the fundamental wave component of the rotating magnetic field and the permanent magnet 26 is provided. Magnet torque acts on the rotor 14 due to the interaction between the attraction and repulsion.

  Further, when the rotating magnetic field acts on the rotor 14 from the stator 12, fluctuations in leakage magnetic flux leaking into the slot 48 between the rotor salient poles 28n and 28s are generated due to magnetic flux fluctuations of spatial harmonics included in the rotating magnetic field. When the fluctuation of the leakage magnetic flux is sufficiently large, an induced current is generated in at least one of the rotor windings 24n and 24s arranged in the slot 48. When an induced current is generated in the rotor windings 24n and 24s, the induced current is rectified by the diodes 30 and 32 to be in a predetermined direction. Then, as the current rectified by the diodes 30 and 32 flows through the rotor windings 24n and 24s, the rotor salient poles 28n and 28s are magnetized, and the rotor salient poles 28n and 28s are magnetic poles having a desired polarity. Function as. In this case, due to the difference in the rectification directions of the diodes 30 and 32, N poles and S poles are alternately arranged in the circumferential direction as magnetic poles generated by the induced currents of the rotor salient poles 28n and 28s.

  Further, in the rotating electrical machine drive system 10, as described with reference to FIG. 3A, the timing t0 from the immediately preceding ta at which the salient poles 19 and the rotor salient poles 28n and 28s of different polarities face each other at a predetermined timing. Until then, the pulse superimposing unit 46 superimposes the pulse current on the stator current of the predetermined phase. As a result, a leakage magnetic flux is generated in the slot 48, and the fluctuation of the leakage magnetic flux linked to the rotor windings 24n and 24s arranged in the slot 48 can be sufficiently increased. For this reason, an induction current is generated in the rotor windings 24n and 24s, and the rotor salient poles 28n and 28s can be magnetized to a desired polarity. When the salient pole 19 and the rotor salient poles 28n and 28s having different polarities face each other, a magnetic attractive force can be generated between the salient pole 19 and the rotor salient poles 28n and 28s.

  This will be described in more detail with reference to FIGS. In FIG. 4, the rotor salient pole 28 n for forming the N pole faces the salient pole 19 of the S pole of the stator 12, and FIG. 5 shows the rotor salient pole 28 s for forming the S pole of the salient pole 19 of the stator 12. Are opposed to each other, and the rotor 14 rotates in each case. In both cases of FIGS. 4 and 5, the leakage flux is linked to the rotor windings 24n and 24s in the direction of the broken arrow or in the opposite direction due to the superposition of the pulse current on the stator current of the predetermined phase, and the fluctuation thereof. Is large enough. Therefore, induced currents in the directions of arrows α1 and α2 that are rectified by the diodes 30 and 32 flow through the rotor windings 24n and 24s, and flow in the directions of the arrows β1 and β2 due to the induced currents in the rotor salient poles 28n and 28s. Magnetic flux flows. In this case, an N pole or an S pole is formed at the tips of the rotor salient poles 28n and 28s, and the rotor 14 rotates in the direction of the arrow γ by being attracted to the salient poles 19 having different polarities. 4 and 5, the magnetization direction of the permanent magnet 26 coincides with the magnetization direction of the rotor salient poles 28 n and 28 s caused by the induced current, so that magnetic attraction between the permanent magnet 26 and the salient pole 19 is also effective. It also shows that the rotor 14 can be rotated.

  As a result, the winding magnetomotive force torque acts on the rotor 14 due to the magnetic attraction interaction between the rotor salient poles 28n and 28s magnetized by the induced current and the fundamental wave component of the rotating magnetic field.

  On the other hand, as described with reference to FIG. 3B, the pulse superimposing unit 46 performs the opposing time including the opposing time point t0 between the salient pole 19 having the same polarity and the rotor salient poles 28s and 28n, immediately before and immediately after the opposing. The pulse current is not superimposed on the stator current of the predetermined phase. For this reason, the fluctuation of the leakage magnetic flux linked to the rotor windings 24n and 24s cannot be sufficiently obtained, and no induction current is generated in the rotor windings 24n and 24s. Therefore, the rotor salient poles 28n and 28s are not magnetized by the induced current. In this case, even when the rotor salient poles 28n and 28s having the same polarity approach the salient pole 19, no magnetic repulsive force is generated.

  This will be described in detail with reference to FIGS. In FIG. 6, the S salient rotor salient pole 28 s faces the S pole salient pole 19 of the stator 12, and FIG. 7 shows the N salient rotor salient pole 28 n of the stator 12 N pole salient pole 19. Are opposed to each other, and the rotor 14 rotates in each case. In both cases of FIGS. 6 and 7, since the pulse current is not superimposed on the stator current of the predetermined phase, the leakage flux having such a large fluctuation as to generate the induced current does not interlink with the rotor windings 24s and 24n. For this reason, no induced current is generated in the rotor windings 24s and 24n, and the rotor salient poles 28s and 28n are not magnetized by the induced current. Therefore, the rotor salient poles 28s and 28n magnetized by the induced current do not approach the salient pole 19 having the same polarity, and no magnetic repulsive force is generated by the induced current. In this case, the permanent magnet 26 having a radially outer polarity that is the same as the salient pole 19 faces the salient pole 19, but the magnetic flux of the permanent magnet 26 is not large enough to repel the salient pole 19 by itself. Further, as will be described later, since the magnetic flux of the permanent magnet 26 loops in the directions of the arrows δ1 and δ2 in FIGS. 6 and 7 in the rotor salient poles 28s and 28n, no repulsive force is generated between the salient poles 19.

  On the other hand, the main magnetic flux in the directions of arrows η1a and η1b in FIG. 6 flows to the salient pole 19 from the right side in FIG. 6, which is the front side in the rotation direction of the rotor salient pole 28s. Further, the main magnetic flux in the directions of arrows η2a and η2b in FIG. 7 flows from the salient pole 19 to the right side in FIG. 7 which is the front side in the rotation direction of the rotor salient pole 28n. This main magnetic flux is a magnetic flux generated by the stator windings 18u, 18v, 18w in order to generate a reluctance torque between the stator 12 and the rotor 14. In this case, the rotor salient poles 28s and 28n are attracted to the salient poles 19 so as to shorten the path of the main magnetic flux, and the torque can be improved by rotating the rotor 14 in the arrow γ direction. Further, since the permanent magnet 26 is arranged on the rotor salient poles 28s and 28n, if the magnetic flux hinders the flow of the main magnetic flux, the rotor salient poles 28s and 28n cannot be effectively attracted to the salient pole 19, but the magnetic flux The flow restriction part 33 facilitates the main magnetic flux to flow through the rotor salient poles 28s and 28n.

  The reason for this will be described in detail. In the present embodiment, the magnetic flux flow restricting portion 33 having a lower magnetic permeability than the rotor salient poles 28 s and 28 n is provided inside the rotor salient poles 28 s and 28 n adjacent to both sides in the circumferential direction of the permanent magnet 26. Since the average length of the loop of the magnetic flux path becomes longer and the width of the loop becomes narrower, the loop is hardly generated. Further, the main magnetic flux at the time of rotor rotation tends to pass on the front side in the rotational direction of the rotor salient poles 28s, 28n. For this reason, the magnetic flux of the permanent magnet 26 is likely to loop on the rear side in the rotational direction of the rotor salient poles 28s and 28n, and conversely, it is difficult to loop on the front side in the rotational direction. The flow is not easily obstructed by the magnetic flux of the permanent magnet 26. Furthermore, since the permanent magnet 26 is adjacent to the magnetic flux flow restricting portion 33 in the circumferential direction, the circumferential width of the permanent magnet 26 is reduced, and the amount of magnetic flux is not excessive. Therefore, even when the rotor salient poles 28s, 28n are excited by the main magnetic flux from the stator 12 in the direction opposite to the magnetization direction of the permanent magnet 26 as shown in FIGS. 6 and 7, the magnetic flux of the permanent magnet 26 is the main magnetic flux. The main magnetic flux easily flows to the front side in the rotational direction of the rotor salient poles 28s and 28n. As a result, the rotor torque can be increased by effectively utilizing the magnetic attractive force between the stator 12 and the rotor 14.

  On the other hand, in the configuration described in Patent Document 1, since the permanent magnet substantially blocks the portion through which the main magnetic flux of the rotor magnetic pole portion passes, it may be an obstacle when the permanent magnet passes the reverse magnetic flux. . Moreover, the main magnetic flux from the stator may be difficult to enter because the magnetic flux of the permanent magnet loops at the magnetic pole part. Moreover, in the structure described in patent document 2, since a permanent magnet is arrange | positioned at the radial direction inner part of a rotor core, and the magnetic flux which circulates around a radial direction inner part flows, a magnetic flux can be flowed to a magnetic pole part as aimed. Can not. In this embodiment, both of these points can be improved.

  FIG. 8 is a schematic diagram showing how the magnetic flux of the permanent magnet 26 loops in the rotor salient pole 28n in the rotor 14 of FIG. In FIG. 8, two magnetic fluxes are looped on both sides of the permanent magnet 26, because this shows a state before the main magnetic flux flows from the stator 12 to the rotor salient pole 28n. As shown in FIG. 8, the magnetic flux flow restricting portion 33 protrudes upward in FIG. 8, which is outside the outer surface Q of the permanent magnet 26 in the rotor radial direction. Without being too close to the radially outer end face, the magnetic flux of the permanent magnet 26 can be effectively restricted from flowing to the front side in the rotational direction of the rotor salient pole 28n, for example, the right side in FIG. Since the permanent magnet 26 is not too close to the radially outer end face of the rotor salient pole 28n, the strength of the rotor salient pole 28n can be increased.

  Further, since the radially outer surface P of the magnetic flux flow restricting portion 33 is tapered, it is possible to restrict the magnetic flux flowing to the front side in the rotational direction of the permanent magnet 26 at the radially outer end H of the outer surface P, and to restrict the magnetic flux flow. Compared with the case where the cross section of the portion 33 is rectangular, the cross sectional area of the notch 34 can be reduced, and the strength of the rotor salient pole 28n can be further increased. Further, since the radially inner end of the notch 34 is positioned radially outward from the radially inner side surface R of the permanent magnet 26, the strength of the rotor salient pole 28n and the support strength of the permanent magnet 26 can be increased. In addition, the shape of the magnetic flux flow restriction | limiting part 33 is not limited to the shape of FIG. 8, A various shape is employable. For example, the taper of the radially outer side surface P of each magnetic flux flow restricting portion 33 can be inclined to the opposite side to the case of FIG. Moreover, the radial direction outer side surface P of each magnetic flux flow restriction | limiting part 33 is not made into a taper shape, but the whole can also be made into a rectangular cross section.

  FIG. 9 is a schematic diagram showing how the magnetic flux of the permanent magnet 26 loops in the rotor salient pole 28n in the rotor 14 of another example of the embodiment of the present invention. As shown in the example of FIG. 9, the magnetic flux flow restricting portion 33 may have a rectangular cross section, and the outer surface P of the magnetic flux flow restricting portion 33 may be provided at a position that coincides with the outer surface Q of the permanent magnet 26 in the radial direction. .

  In the above embodiment, since the magnetic flux flow restricting portions 33 are provided on both sides of the permanent magnet 26 in the circumferential direction, the magnetic force between the stator 12 and the rotor 14 can be increased even when the rotor 14 rotates in the reverse direction to the normal rotation. The rotor torque can be improved by effectively using the suction force. In addition, when the rotor 14 rotates only in one direction, or when a torque improvement in one direction is particularly required, the magnetic flux flow restricting portion 33 is provided only on the front side in one direction of rotation of the rotor salient poles 28n and 28s. It may be provided.

  In the above embodiment, when the salient poles 19 face the rotor salient poles 28n and 28s having different polarities depending on the induced current, the pulse current is superimposed on the stator current of a predetermined phase from the ta immediately before facing to the facing time t0. ing. However, as another example, the pulse current may be superimposed on the stator current of a predetermined phase even during the period from the facing time t0 to immediately after facing where there is a predetermined phase difference.

  Further, when the rotor salient poles 28n and 28s having the same polarity are opposed to the salient pole 19 by the induced current, the pulse superimposing unit 46 prevents the pulse current from being superimposed on the stator current of a predetermined phase. However, as another example, the pulse superimposing unit 46 is configured so that an induced current flows through the corresponding rotor windings 24n and 24s after the rotor salient poles 28n and 28s are attracted to the salient pole 19 at the opposing time t0. It is good also as a structure which superimposes a pulse current on the stator current of a phase. According to this configuration, the torque of the rotating electrical machine 11 can be increased by utilizing the magnetic repulsion between the salient pole 19 and the rotor salient poles 28n and 28s.

  Further, in each of the rotor salient poles 28n and 28s, an auxiliary salient pole made of a magnetic material that is inclined or curved so as to be radially outward from one circumferential side surface or both side surfaces toward the tip may be projected. According to this configuration, the magnetic flux of spatial harmonics of the rotating magnetic field generated in the stator 12 can be effectively guided to the rotor salient poles 28n and 28s, and the torque of the rotating electrical machine 11 can be improved.

  As mentioned above, although the form for implementing this invention was demonstrated, this invention is not limited to such embodiment at all, and it can implement with a various form in the range which does not deviate from the summary of this invention. Of course. For example, the case where the stator winding is wound around the stator by concentrated winding has been described. However, if the stator can generate a rotating magnetic field including spatial harmonics, the stator winding may be wound around the stator by distributed winding. Good.

  In the above description, the rotating electric machine in which the rotor winding is wound around the rotor salient pole has been described. However, the rotor salient pole is adjacent to the rotor salient pole in the circumferential direction in a configuration in which the rotor winding is not wound around the rotor salient pole. It is good also as a structure which provides a magnetic flux flow restriction | limiting part.

  DESCRIPTION OF SYMBOLS 10 Rotating electrical machinery drive system, 11 Rotating electrical machinery, 12 Stator, 13 Drive part, 14 Rotor, 16 Stator core, 18u, 18v, 18w Stator winding, 19 Salient pole, 20 Slot, 21 Rotating shaft, 22 Rotor core, 24n, 24s Rotor Winding, 26 Permanent magnet, 28n, 28s Rotor salient pole, 30 1st diode, 32 2nd diode, 33 Magnetic flux flow limiter, 34 Notch, 36 Resin member, 40 Power storage device, 42 Inverter, 44 Controller, 46 Pulse superposition part, 48 slots.

Claims (4)

A rotor of a rotating electrical machine including a rotor core including rotor salient poles provided at a plurality of locations in the circumferential direction,
A permanent magnet embedded in each rotor salient pole and having a magnetization direction in the rotor radial direction; and provided in the interior of each rotor salient pole adjacent to the permanent magnet in the circumferential direction; A rotor of a rotating electrical machine including a magnetic flux flow restricting portion having a low magnetic permeability. The rotor of the rotating electrical machine according to claim 1,
The magnetic flux flow restricting portion includes a notch portion provided in each rotor salient pole adjacent to the permanent magnet in a circumferential direction, and a nonmagnetic member embedded in the notch portion. Rotor for rotating electrical machines. In the rotor of the rotating electrical machine according to claim 1 or 2,
The rotor of a rotating electrical machine, wherein the magnetic flux flow restricting portion is projected outward from an outer end face of the permanent magnet in the rotor radial direction. In the rotor of the rotary electric machine according to any one of claims 1 to 3,
The permanent magnets embedded in the rotor salient poles adjacent to each other in the circumferential direction have different magnetization directions from each other.
The rotor windings wound around the rotor salient poles and the magnetization directions generated in the rotor salient poles by rectifying the induced current generated in the rotor windings in one direction coincide with the magnetization directions of the permanent magnets. A rotor of a rotating electrical machine comprising:

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