JP2015159691A - Permanent magnet rotary electric machine and control apparatus of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve a permanent magnet rotary electric machine capable of performing low torque high speed rotation.SOLUTION: A permanent magnet rotary electric machine 1 is constituted of a stator 10 having an armature coil 11 that generates a rotating magnetic field of a plural number of poles and a rotor 20 having a permanent magnet 21. By irreversibly magnetizing part of the permanent magnet 21 with an external magnetic field, a magnetization distribution of the permanent magnet at each magnetic pole is made to be changed from a symmetrical state to an asymmetrical state.

Description

  The present invention relates to a permanent magnet rotating electrical machine having a variable maximum torque phase and a permanent magnet rotating electrical machine control device.

  2. Description of the Related Art In recent years, as a rotating electric machine having a variable torque, one that performs flux-weakening control on an embedded permanent magnet (IPM) motor is known. Since the rare earth element permanent magnet generates a magnetic force several tens of times that of the conventional magnet, a high output and high efficiency motor can be obtained. In such an IPM motor using a permanent magnet, flux weakening control is applied to drive the motor in a medium to high speed rotation range under conditions where the maximum power supply voltage such as a battery or overhead wire voltage is limited. Weak magnetic flux control uses inverter control to cause negative d-axis current to flow in the motor armature winding to create a linkage flux in the opposite direction to the linkage flux of the permanent magnet, thereby reducing the total linkage flux. Suppresses the occurrence of overvoltage at high speed. The IPM motor is a permanent magnet rotating electric machine having a magnetic structure in which this control works effectively.

  However, the conventional permanent magnet rotating electrical machine also has the following problems. That is, the torque of the embedded permanent magnet (IPM) motor is composed of a permanent magnet torque (PM torque) component and a reluctance torque (Re torque) component. The current phase angle at which the torque becomes maximum differs between the PM torque component and the Re torque component. The current phase of Re torque is twice the frequency and opposite to the current phase of PM torque. Therefore, the total torque of the entire motor is lower than the sum of the maximum values of the two torque components. That is, the magnetic flux of the permanent magnet is not effectively utilized at the maximum torque point as a motor. Rather, a part of the permanent magnet generates a negative torque at the maximum torque point of the motor.

  Therefore, if a motor having a variable current phase difference between the waveform of the PM torque component and the waveform of the Re torque component can be created, both the PM torque component and the Re torque component can be effectively used, and improvement in motor performance can be expected.

Kazuhito Tsuji, Kazuaki Yuki, Yutaka Hashiba, Norio Takahashi, Kazuya Yasui, Go-Wutty Kunlanshi Lilit, "Principle and Basic Characteristics of Variable Magnetic Memory Motor", D. Vol.131, No.1, pp53- 60 (2011) K. Sakai, N. Yuzawa and H. Hashimoto: “Permanent magnet motors capable of pole changing and three-production mode using magnetization”, IEEJ Journal IA, No. 2, No. 6 (2013)

  The present invention has been made in view of the above-described problems of the prior art, and by changing the magnetization distribution state of each permanent magnet embedded in the rotor asymmetrically, the current phase angle characteristic of the PM torque component is changed, It is an object of the present invention to provide a permanent magnet rotating electrical machine and a permanent magnet rotating electrical machine control device capable of effectively converting both PM torque component and Re torque component into motor torque and having a variable maximum torque phase.

  The present invention includes a stator having an armature winding that generates a rotating magnetic field having a plurality of poles and a rotor having a permanent magnet, and irreversibly magnetizes a part of the permanent magnet with an external magnetic field. The permanent magnet rotating electrical machine changes the magnetization distribution of the permanent magnet in each magnetic pole from a symmetric state to an asymmetric state distribution.

  The present invention is also a control device for controlling the rotation of the permanent magnet rotating electric machine, characterized in that the amount of magnets that irreversibly changes the magnetization state of the permanent magnets is changed according to operating conditions.

  According to the permanent magnet rotating electrical machine and the permanent magnet rotating electrical machine control device of the present invention, the current phase angle characteristic of the PM torque component is changed by irreversibly changing the magnetization distribution state of each permanent magnet of the rotor, and the PM Both the torque component and the Re torque component can be effectively converted into motor torque.

1 is a cross-sectional view of an IPM motor according to an embodiment of the present invention. Sectional drawing of the rotor in the IPM motor of the said embodiment. The block diagram of the control apparatus which controls rotation of the IPM motor of the said embodiment. The flowchart of the control which changes the magnetization distribution state of the permanent magnet of the IPM motor by the said control device irreversibly. Sectional drawing which shows the state which changed the magnetization state of a part of each permanent magnet of each magnetic pole irreversibly in the rotor of the IPM motor of the said embodiment. Sectional drawing which shows the state which changed irreversibly the one part magnetization state of each permanent magnet of the magnetic pole of a 1st quadrant and a 2nd quadrant in the rotor of the IPM motor of the said embodiment. The figure which shows the item of the IPM synchronous motor model of the Example of this invention. In the IPM synchronous motor of the said Example, the figure which shows the measurement result of the magnetization reversal rate of each magnetic pole, and the electric current phase angle of the maximum torque point with respect to it. The graph which shows the torque versus electric current phase characteristic for every magnetization reversal ratio of each magnetic pole of the IPM synchronous motor of the said Example. The graph which shows the torque and speed characteristic for every magnetization reversal ratio of each magnetic pole of the IPM synchronous motor of the said Example. Sectional drawing of the permanent magnet of the rotor used for the permanent magnet rotary electric machine of the 2nd Embodiment of this invention. Sectional drawing of the permanent magnet of the rotor used for the permanent magnet rotary electric machine of the 3rd Embodiment of this invention.

  First, the principle of the permanent magnet motor (VTPS-PM) having a variable maximum torque phase according to the present invention will be described. Since the Re torque component is determined by the rotor core shape, it is difficult to make it variable. Therefore, consider making the current phase of the PM torque component variable. The dq axes are determined by the arrangement of the permanent magnets in the rotor. Therefore, in VTPS-PM, the phase of the PM torque waveform is made variable without changing the position of the permanent magnet by irreversibly demagnetizing or irreversibly reversing the magnetization of a part of the permanent magnet of each magnetic pole. Then, high-torque rotation can be performed in a low-speed rotation region by a power source of a predetermined current and voltage, and when high-speed rotation is required, the rotation speed can be increased to the high-speed rotation region by weakening magnetic flux control.

  In the present application, the meaning of “irreversibly changing the magnetization state” means that a part of the permanent magnet is applied to another part of the permanent magnet by applying a magnetic field several times larger than the magnetic field generated during normal operation (instantaneously). This means that the magnetization state different from the part is changed and the changed magnetization state is maintained unless an external magnetic field is applied. However, even after irreversibly changing the magnetization state, it is possible to reduce the degree of magnetization (demagnetization) by applying another magnetic field, for example, a magnetic field in the reverse direction, or by applying a larger magnetic field. Can be reversed, returned to the original magnetization state, and the degree of magnetization can be increased (magnetization).

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an embedded permanent magnet (IPM) motor 1 adopting the principle of VTPS-PM. The IPM motor 1 shown in FIG. 1 is a 4-pole synchronous motor (IPMSM). The IPM motor 1 has a structure in which a stator 10 having an armature winding 11 that generates a four-pole rotating magnetic field and four permanent magnets 21 are embedded in a rotor core 22 at equal angular intervals in the circumferential direction. It consists of a child 20.

  In the stator 10, here, 24 slots 13 are formed radially on the inner peripheral side of a cylindrical stator core 12, and a three-phase armature winding 11 is wound so as to form a four-pole rotating magnetic field. It is.

  As shown in FIG. 2, in the rotor 20, the rotor core 22 is formed in a cylindrical shape, and a rotating shaft 23 made of a nonmagnetic material is passed through the center of the rotor core 22. Four plate-like permanent magnets 21 are embedded in the rotor iron core 22 so that the circumferential direction is the width direction and the circumferential intervals are arranged at this angular interval. Here, the four permanent magnets 21 are arranged such that the magnetization direction is the radial direction (thickness direction), and the adjacent permanent magnets 21 have the N and S poles opposite to each other. Further, in the rotor 20, a gap 24 for a magnetic barrier is formed in the rotor core 22 in a substantially radial direction from both ends of each permanent magnet 21 to the vicinity of the outer periphery.

  The permanent magnet 21 used for the rotor 20 allows a large current approximately 3 to 6 times larger than the current flowing through the armature winding 11 during normal rotational operation to flow almost instantaneously, for example, in a short time of 0.03 seconds. It has a variable magnetic force characteristic that is irreversibly magnetized, demagnetized, unmagnetized, or polarity-reversed by an external magnetic field. The material is preferably a rare earth magnet, particularly a samarium cobalt magnet. The samarium cobalt magnet has a small residual magnetic flux density and a temperature coefficient of coercive force as compared with the neodymium magnet, and has excellent thermal stability. An appropriate coercive force is used depending on the application and rating. For example, a coercive force of 500 kA / m or less can be used.

  In the rotor 20, a line passing in the radial direction through the center in the circumferential direction (width direction) of the permanent magnet 21 in a normal state without demagnetization or magnetic pole reversal is the d-axis direction, and the radius in the air gap 24 for the magnetic barrier A line passing through the direction is the q-axis direction. In the illustrated embodiment, a four-pole rotor 20 is configured.

  These permanent magnets 21 have the above-described variable magnetic force characteristics, and can be demagnetized, magnetized, reversed in magnetization, or non-magnetized from the end in the width direction at an arbitrary ratio. it can. Thereby, each permanent magnet 21 can be irreversibly changed to an asymmetric magnetization distribution state in the width direction with the thickness direction at the center in the width direction as the axis of symmetry. In order to irreversibly change the magnetization distribution state, a large positive or negative current several times larger than that during normal operation is applied to the armature winding 11 at the timing when the rotor 20 reaches a predetermined rotational position. This is done by energizing for a short time and applying a strong external magnetic field generated by the large current.

  FIG. 3 shows a control device 50 of the IPM motor (IPMSM) 1 having the above structure. The control device 50 includes a speed sensor 51, a current vector controller 52, a current feedback controller 53, a PWM inverter 54, a position sensor such as a pulse generator for detecting the rotational position of the rotor 20 of the IPM motor 1, and a resolver. 55, a rotor position detection unit 56, and a speed detection unit 57. The IPM motor 1 according to the embodiment performs the flux weakening control for reducing the magnetic flux in the d-axis direction by controlling the flow of the negative d-axis current through the armature winding 11 by the control device 50.

  The control operation of the control device 50 is as follows. A pulse having a period proportional to the rotation of the rotor 20 of the IPM motor 1 is generated by the position sensor 55, and this is output to the rotor position detector 56 and the speed detector 57. The rotor position detector 56 detects the rotational position θ of the rotor 20 from the signal of the position sensor 55 and outputs it to the current feedback controller 53. The speed detector 57 detects the rotational speed ω of the rotor 20 and outputs it to the speed controller 51 and the current vector controller 52.

  The speed control unit 51 compares a speed command ω * such as an accelerator depression amount or a microcomputer notch command with the speed detection value ω from the speed detection unit 57, and calculates a q-axis current command iq * from the speed deviation. . The speed control unit 51 outputs the q-axis current command value iq * to the current vector control unit 52 and the current feedback control unit 53. The current vector control unit 52 calculates a d-axis current command value id * by a current vector control algorithm using the speed detection value ω from the speed detection unit 57 and the q-axis current command value iq * from the speed control unit 51. And output to the current feedback control unit 53.

  The current feedback control unit 53 inputs the d-axis current command value id *, the q-axis current command value iq *, the rotor rotation position θ, and the current detection values Iu and Iv from the current detector 58 for the inverter output (Iw Since it can be calculated from Iu and Iv, it does not need to be input.) Based on these, the current vector command value I * is determined. Further, the current feedback control unit 53 obtains voltage command values Vu *, Vv *, Vw * from the current vector command value I *, and outputs them to the PWM inverter 54. The PWM inverter 54 performs PWM (pulse width modulation) on the voltage command values Vu *, Vv *, and Vw * from the current feedback control unit 53, and applies them to the armature windings 11 of the three phases of the IPM motor 1. Necessary currents Iu, Iv, and Iw are supplied, and the rotor 20 of the IPM motor 1 is rotated at a speed that matches the speed command ω *.

  The control device 50 of the permanent magnet rotating electrical machine 1 according to the present embodiment further includes a phase shift control unit 59. As shown in the flowchart of FIG. 4, the phase shift control unit 59 inputs a speed command ω *, a rotor rotational position detection value θ, and a speed detection value ω (step S1).

  When the speed command ω * is switched, the maximum torque command standard table stored therein is referred to, and the phase shift maximum torque corresponding to the speed command ω * is what percentage of the base maximum torque. Is determined (step S2). Further, it is determined whether to accelerate or decelerate from the difference between the speed command ω * and the detected speed value ω. If the current speed is maintained, the process returns as it is (step S3).

  And if it is acceleration and the phase shift maximum torque (requested torque) is 90% of the base maximum torque, for example, it is determined that the torque is suppressed by 10% from the maximum torque state in the current phase, as follows: First-stage magnetization reversal control is performed (steps S41 and S411). On the other hand, if it is determined that 80%, that is, 20% torque suppression with respect to the base maximum torque, the second-stage reversal control is performed (steps S41 and S412).

  Conversely, if the speed is reduced in step S3 and the phase shift maximum torque (required torque) is, for example, 90% of the base maximum torque and the current torque state is 80% of the base maximum torque, the torque increases by one step. Judgment is made, and the first-stage magnetization reinversion control is performed as follows (steps S42 and S421). If the required torque is the base maximum torque (that is, 100%) and the current torque state is 80% with respect to the base maximum torque, it is determined that the two-stage torque is increased, and the second-stage magnetization reinversion control is performed. (Steps S42 and S422).

  This magnetization reversal and magnetization reinversion control is performed by instantaneously flowing a larger current than usual in the armature winding 11 of the stator 10 and also controlling the flow timing. The magnetization reversal control during acceleration will be described with reference to FIGS. A large current is instantaneously passed through the armature winding 11 at a timing shifted in phase by the rotation angle θ ′ from the original d-axis position. This phase difference θ ′ varies depending on the rated characteristics of the IPM motor 1, the magnetic characteristics of the permanent magnet 21, and the ratio of the reverse magnetization portion. Also, the current value is 3 to 6 times larger than the normal motor drive current, although it varies depending on the material of the permanent magnet 21 used. Even if it is impossible to continuously flow such a large current with a battery or an overhead wire power supply with limited capacity and maximum voltage, it is instantaneously less than 1 second, for example, 0.03 seconds. When a large current is generated, such a power supply is not damaged. Further, in order to increase the reversal magnetization portion, a large current is instantaneously passed through the armature winding 11 at a timing shifted by a phase larger than θ ″ (> θ ′).

  When the reversal magnetization portion is reduced from 20% to 10%, a large current is flowed for magnetization reversal at the timing of θ ′, or remagnetization is performed at the original d-axis position timing. Two-stage control is performed in which a large current is applied again for magnetization reversal at the timing of θ ′ after the current of. When the reversal magnetization portion is reduced from 10% to 0%, a large current opposite to the above is applied to reinvert magnetization at the original d-axis position timing.

  By passing such a magnetization reversal current, a part of the permanent magnet 21-1 at the position corresponding to the first quadrant in FIG. Further, a part of the permanent magnet 21-2 at the position corresponding to the second quadrant in FIG. Thereby, for example, the permanent magnet 21-1 has a 90% magnetization non-inversion part 21A- and a 10% magnetization inversion part 21B +, and the permanent magnet 21-2 has a 90% magnetization non-inversion part 21A + and a 10% magnetization inversion. Part 21B- is generated. In the case of 20% magnetization reversal, the permanent magnet 21-1 includes an 80% magnetization non-inversion portion 21A- and a 20% magnetization reversal portion 21B +, and the permanent magnet 21-2 includes an 80% magnetization non-inversion portion. 21A + and 20% magnetization reversal part 21B- are generated. Although not shown in FIG. 6, the permanent magnet 21-3 at a position corresponding to the third quadrant that is point-symmetric via the rotating shaft 23 is the same as the permanent magnet 21-1 at a position corresponding to the first quadrant. Magnetization reversal part 21B + occurs in part, and permanent magnet 21-4 at the position corresponding to the fourth quadrant is partially magnetized reversal part 21B- like the permanent magnet 21-2 at the position corresponding to the second quadrant. Occurs.

  On the other hand, at the time of deceleration, it is necessary to cope with an increase in the required torque by the magnetization reinversion control. If there is a deceleration command such as when the brake is depressed, the notch is lowered, etc. in a low torque, high speed operation state due to 20% magnetization reversal, the magnetization reversal part of the permanent magnet 21 is only 10% by the above control. Re-invert or 20% re-invert. As a result, the magnetization direction of the magnetization reversal part so far is returned to the same direction as that of the remaining magnetization parts by 10% or 20%.

  When performing power generation (regeneration) with a motor, or when applying as a generator, in the figure described above, by performing magnetization reversal on the left end of the magnet opposite to the above, Get the same action and effect.

  Next, the torque phase and motor characteristics by variable magnetization will be described for the motor model having the specifications shown in FIG. This motor model is a four-pole permanent magnet synchronous motor, and has an outer diameter of the stator 10 of 120 mm, 24 slots, an outer diameter of the rotor 20 of 60 mm, an iron core length of 60 mm, and a magnetic gap of 0.5 mm. The number of armature windings is 12, the number of turns is 35, the rated current is 3.5 Arms, and the permanent magnet 21 is a samarium cobalt magnet having a low coercive force of 100 to 300 kA / m, and has a width of 22 mm and a thickness of 3.5 mm. As shown in FIG. 1, they are arranged so that the cross section is substantially square.

  With respect to the motor model, as shown in FIG. 5, the permanent magnet 21 of each magnetic pole was partially magnetized from one end thereof, and a magnetic field analysis was performed using the ratio% of the magnetized reversal as a parameter. The obtained motor characteristics were as follows.

1. Torque vs. Current Phase Characteristics FIG. 8 shows the current phase angle at the maximum torque point when the current phase is changed, and FIG. 9 shows the torque characteristics. The current is 3.5A.

  In a normal IPM motor in which magnetization reversal is impossible, the current phase angle at the maximum torque point is 115 °. This is because the reluctance torque (Re torque) component is synthesized while the maximum torque point of the permanent magnet torque (PM torque) component is 90 ° in the d-axis direction.

  In contrast, 9% (A1 curve), 18% (A2 curve), 27% (A3 curve), 36% (A4 curve), 45% (A5 curve) and one of the permanent magnets 21 When the magnetization is reversed so that the portion is in an asymmetric magnetization distribution state, the current phase angle at the maximum torque point is shifted in a direction (leading phase). When the magnet ratio of the magnetization reversal portion is about 45%, the current phase angle that is the maximum torque is shifted to 157 °.

2. Variable speed characteristics Magnetic field analysis was performed on the variable speed characteristics when magnetization was partially reversed within an arbitrary range. FIG. 10 shows torque versus rotational speed (TN) characteristics when the magnetization reversal region is changed from 0 to 45%. In the normal IPM mode, the maximum torque is 2.8 Nm, the base speed is 3200 rpm, and the maximum rotation speed by the flux-weakening control is 5600 rpm as shown by the curve A1. In the 9% magnetization reversal indicated by the curve A2, the maximum torque is 2.3 Nm, the base speed is 3800 rpm, the maximum rotation speed by the flux weakening control is 8800 rpm, and in the 18% magnetization reversal indicated by the curve A3, the maximum torque is 1.7 Nm, the base The speed is 4400 rpm, and the maximum rotation speed by the flux weakening control is 15000 rpm. It was found that when the magnetization is reversed and the maximum torque phase angle is shifted in the advance direction, the output in the medium to high speed rotation region is improved and the maximum rotation speed can be increased up to about three times.

  In the middle to high speed range above the base speed, the weak flux control for suppressing overvoltage and the lead phase control for increasing the power factor are performed. The reason for the improvement in output performance in the medium to high speed range is that the IPM motor of this embodiment can shift the maximum torque phase angle in accordance with the current advance phase, so that the magnetic flux can be used effectively. For this reason, it was confirmed that the output in the medium to high speed range could be greatly improved by varying the maximum torque phase according to the variable speed operation.

  In the embodiment of the present invention, the IPM motor is exemplified as the permanent magnet rotating electric machine. However, the power generation (regeneration) operation by the motor and the permanent magnet rotating electric machine can be applied to the generator. Further, when the present invention is applied specifically to a permanent magnet motor, it is not the permanent magnet 21 having variable magnetic force characteristics that can reverse the magnetic pole irreversibly by an instantaneous large current as shown in FIG. As shown in FIG. 4, the permanent magnet 212 having such a variable magnetic force characteristic in a part in the width direction, and the remaining part is a fixed magnetic force characteristic that does not irreversibly demagnetize or reverse magnetization even by such an instantaneous large current. A permanent magnet 21 ′ composed of a permanent magnet 211 having the above can be employed. In that case, a permanent magnet motor (VTPS-PM) having a variable maximum torque phase is configured by performing magnetic pole reversal control on the permanent magnet 212 having variable magnetic force characteristics, as in the IPM motor 1 of the present embodiment. be able to.

  Further, as shown in FIG. 12, permanent magnets 212 and 212 having variable magnetic force characteristics at both end portions in the width direction, and a fixed magnetic force in which the central portion irreversibly neither demagnetizes nor reverses magnetization even by an instantaneous large current. It is also possible to employ a permanent magnet 21 ″ composed of a permanent magnet 211 having characteristics. In this case, the IPM motor of the present embodiment is controlled by performing magnetic pole reversal control on the permanent magnet 212 having variable magnetic characteristics. A permanent-magnet motor (VTPS-PM) having a variable maximum torque phase can be configured in the same manner as in 1. It can also be applied to a permanent-magnet rotating electric machine such as a generator.

  In addition, in the above embodiment, the magnetization direction of the end portion of the permanent magnet 21 is irreversibly reversed to cope with the high-speed rotation range. However, the magnetic force is irreversibly only at the end portion of the permanent magnet 21. The current phase angle of the maximum torque of the PM torque component can be changed by demagnetizing to. Further, the current phase angle of the maximum torque of the PM torque component can be changed by irreversibly setting the magnetic force to only the end portion of the permanent magnet 21. Furthermore, the current phase angle of the maximum torque of the PM torque component can be finely changed by combining irreversible reversal of the magnetization direction at the end of the permanent magnet, non-magnetization, and demagnetization.

  Furthermore, although the permanent magnet quadrupole synchronous motor (IPMSM) has been described in the above embodiment, the number of poles, the number of slots, and the number of phases of the power source are not limited. Further, there is no limitation on direct current and alternating current. Furthermore, the arrangement of the variable magnetic force permanent magnets is not limited to that arranged in a regular square shape in the rotor core. For example, a configuration may be adopted in which each pair of variable magnetic magnets is arranged in an inverted 8-character shape that opens to the outer peripheral side of the rotor.

  Thus, according to the permanent magnet rotating electric machine of the present invention, the current phase difference between the waveform of the PM torque component and the waveform of the Re torque component can be changed, and both the PM torque component and the Re torque component can be effectively utilized. Performance can be improved.

  INDUSTRIAL APPLICABILITY The present invention can be widely applied to the fields of social systems and home appliances such as hybrid vehicles / electric vehicles, transportation systems such as railways, energy systems such as wind power generation and ocean current power generation, home appliances such as elevators and air conditioners.

1 IPM motor (permanent magnet motor)
DESCRIPTION OF SYMBOLS 10 Stator 11 Armature winding 12 Stator iron core 20 Rotor 21 Permanent magnet 21A ± Magnetization non-inversion part 21B ± Magnetization inversion part 22 Rotor core 23 Rotating shaft 24 Air gap (as magnetic barrier)

Claims (11)

A stator having an armature winding that generates a rotating magnetic field having a plurality of poles, and a rotor having a permanent magnet,
A permanent magnet rotating electrical machine characterized in that a part of the permanent magnet is irreversibly magnetized by an external magnetic field to change the magnetization distribution of the permanent magnet in each magnetic pole from a symmetric state to an asymmetric state distribution. A stator having an armature winding that generates a rotating magnetic field having a plurality of poles, and a rotor having a permanent magnet,
A permanent magnet rotating electrical machine characterized in that the permanent magnet is irreversibly magnetized by an external magnetic field, whereby the magnitude of magnetization at one end of the permanent magnet at each magnetic pole is variable. A stator having an armature winding that generates a rotating magnetic field having a plurality of poles, and a rotor having a permanent magnet,
A permanent magnet rotating electrical machine characterized in that the permanent magnet is irreversibly magnetized by an external magnetic field to partially reverse the polarity of one end of the permanent magnet in each magnetic pole. A stator having an armature winding that generates a rotating magnetic field having a plurality of poles, and a rotor having a permanent magnet,
The permanent magnet is irreversibly magnetized by an external magnetic field, so that the degree of magnetization at one end of the permanent magnet at each magnetic pole can be increased or decreased, or the polarity can be reversed, and the degree of magnetization can be increased or decreased. A permanent magnet rotating electrical machine characterized in that the amount of magnet to be reversed is variable.   5. The permanent magnet rotating electric machine according to claim 1, wherein the external magnetic field is a magnetic field generated by an armature current, and a part of the permanent magnet is irreversibly magnetized by the magnetic field generated by the armature current. A permanent magnet rotating electric machine characterized in that   The permanent magnet rotating electric machine according to any one of claims 1 to 5, wherein a coercive force of at least a portion of the permanent magnet that irreversibly changes a magnetization state is equal to or less than a coercive force of a normal rare earth magnet. Permanent magnet rotating electric machine.   The permanent magnet rotating electric machine according to any one of claims 1 to 6, wherein a coercive force of a portion of the permanent magnet that changes the magnetization state irreversibly is 500 kA / m or less. .   The permanent magnet rotating electric machine according to any one of claims 1 to 7, wherein portions of the permanent magnet that irreversibly change the magnetization state are both ends in the circumferential direction of the permanent magnet, and motor operation and power generation A permanent magnet rotating electrical machine characterized in that the end is on the opposite side in the circumferential direction.   The permanent magnet rotating electric machine according to any one of claims 1 to 8, wherein each of the magnetic pole portions of the permanent magnet has a low coercive force permanent magnet whose irreversible state changes due to an external magnetic field of a predetermined value or more. The permanent magnet rotating electric machine is characterized in that the central portion is constituted by a high coercivity permanent magnet whose magnetization state is not irreversibly changed even by an external magnetic field of a predetermined value or more.   The control device for controlling rotation of the permanent magnet rotating electric machine according to any one of claims 1 to 9, wherein the amount of the magnet that irreversibly changes the magnetization state of the permanent magnet is changed according to an operation state. A permanent magnet rotating electrical machine control device.   11. The permanent magnet rotating electrical machine control device according to claim 10, wherein the magnetized state of the permanent magnet is irreversible by flowing a large current, which is larger than a current flowing through the armature winding during normal operation, by a predetermined time. Permanent magnet rotating electrical machine control device, characterized in that it is changed in a mechanical manner.

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