JP2006280195A - Permanent magnet type rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permanent magnet type rotary electric machine which can execute variable speed operation in a wide range of from a low speed to a high speed, with a high output, and to realize improvement of efficiency and reliability. <P>SOLUTION: The permanent magnet type rotary electric machine is constituted by a stator provided with a winding, a permanent magnet having low coercive force to the extent of the magnetic flux density being changed irreversibly by a magnetic field generated by a current in the stator winding, and a rotor arranging the permanent magnet of high coercive force, having the coercive force of two times or more the low coercive force. In a high-speed rotational region, generating the maximum voltage or higher of the power source voltage, the permanent magnet of low coercive force is magnetized by the magnetic field due to the current with a total inter-linkage magnetic flux by the permanent magnet of low/high coercive force, so as to make the amount of the total inter-linkage magnetic flux decrease and the total inter-linkage magnetic flux is adjusted. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a permanent magnet type rotating electrical machine.

  Generally, permanent magnet motors are roughly divided into two types. These are a surface magnet type permanent magnet motor in which a permanent magnet is attached to the outer periphery of a rotor core and an embedded type permanent magnet motor in which a permanent magnet is embedded in the rotor core. An embedded permanent magnet motor is suitable as the variable speed drive motor.

  The configuration of the rotor of the embedded permanent magnet motor will be described with reference to FIG. In FIG. 19, 11 is a rotor, 12 is a rotor core, and 14 is a high coercivity permanent magnet. A rectangular cavity is provided in the outer peripheral portion of the rotor core 12 by the same number as the number of poles. FIG. 19 shows a four-pole rotor 11 in which four cavities are provided and a permanent magnet 14 is inserted. The permanent magnet 14 is magnetized in the radial direction of the rotor or in the direction perpendicular to the side facing the air gap surface in the rectangle of the cross section of the permanent magnet 14. The permanent magnet 14 is mainly an NdFeB permanent magnet having a high coercive force so as not to be demagnetized by a load current. The rotor core 12 is formed by laminating electromagnetic steel plates punched out of cavities. Such a conventional example is described in “Design and Control of an Embedded Magnet Synchronous Motor”, Yoji Takeda et al., Issued by Ohm (Non-Patent Document 1), and an embedded type modification is disclosed in Japanese Patent Laid-Open No. 7-336919. It is described in the gazette (patent document 1). Further, as a motor with excellent variable speed characteristics and high output, a permanent magnet type reluctance described in Japanese Patent Application Laid-Open No. 11-27913 (Patent Document 2) and Japanese Patent Application Laid-Open No. 11-136912 (Patent Document 3). There is a type rotating electrical machine.

  In the permanent magnet type rotating electrical machine, the interlinkage magnetic flux of the permanent magnet is always generated at a constant value, so that the induced voltage by the permanent magnet increases in proportion to the rotational speed. In variable speed operation from low speed to high speed, the induced voltage by the permanent magnet becomes extremely high at high speed rotation, and when the induced voltage by the permanent magnet is applied to the electronic components of the inverter and exceeds the withstand voltage of the electronic components, the components break down. To do. For this reason, it is conceivable to perform a design in which the amount of magnetic flux of the permanent magnet is reduced so as to be equal to or lower than the withstand voltage.

  When performing variable speed operation close to constant output from low speed to high speed, the flux linkage of the permanent magnet is constant, so the rotating electrical machine voltage reaches the upper limit of the power supply voltage in the high-speed rotation range and the current required for output does not flow. . As a result, the output is greatly reduced in the high speed region, and further, it becomes impossible to drive in a wide range up to the high speed. Recently, the flux weakening control (see Non-Patent Document 1) has begun to be applied as a method for expanding the variable speed range. . In the flux weakening control, a demagnetizing field due to the d-axis current is applied to the high coercive force permanent magnet 4, and the magnetic operating point of the permanent magnet is moved within a reversible range to change the amount of magnetic flux. For this reason, a NdFeB magnet having a high coercive force is applied to the permanent magnet so that it is not irreversibly demagnetized by a demagnetizing field.

  Since the interlinkage magnetic flux of the permanent magnet decreases due to the demagnetizing field of the d-axis current, the decrease of the interlinkage magnetic flux creates a voltage margin with respect to the voltage upper limit value. Since the current can be increased, the output in the high speed region increases. Further, the rotational speed can be increased by the voltage margin, and the range of variable speed operation is expanded.

  However, it is necessary to continue to apply a demagnetizing field to the permanent magnet, and since the d-axis current that does not contribute to the output is continuously supplied, the copper loss increases and the efficiency deteriorates. Further, the demagnetizing field due to the d-axis current generates a harmonic magnetic flux, and the increase in voltage generated by the harmonic magnetic flux or the like is weakened, creating a limit of voltage reduction by the magnetic flux control. Therefore, even if the flux-weakening control is applied to the embedded permanent magnet type rotating electric machine, it is difficult to operate at a variable speed that is three times or more the base speed. Furthermore, the iron loss is increased by the harmonic magnetic flux, and vibration is generated by the electromagnetic force generated by the harmonic magnetic flux.

  Further, when an embedded permanent magnet motor is applied to a drive motor for a hybrid vehicle, the motor is rotated in a state where it is driven only by an engine. At medium / high speed rotation, the induced voltage of the motor's permanent magnet exceeds the power supply voltage, and the d-axis current continues to flow under the flux-weakening control. In this state, since the motor generates only a loss, the overall operation efficiency is deteriorated.

When an embedded permanent magnet motor is applied to a train drive motor, the train is in a coasting state, and the d-axis current continues to flow with a flux weakening control so that the induced voltage by the permanent magnet is equal to or lower than the power supply voltage in the same manner as described above. . Since the motor generates only a loss, the overall operation efficiency deteriorates.
JP 7-336919 A JP-A-11-27913 JP-A-11-136912 "Design and control of embedded magnet synchronous motor", Yoji Takeda, etc., published by Ohm

  The present invention has been made in view of the problems of the prior art as described above, and enables variable speed operation in a wide range from low speed to high speed, with high torque in the low speed rotation range and in the middle / high speed rotation range. An object of the present invention is to provide a permanent magnet type rotating electrical machine that can provide higher output, improved efficiency, and improved reliability.

  The permanent magnet type rotating electrical machine according to the present invention has a coercive force such that the magnetic flux density is irreversibly changed by a magnetic field generated by a current of the stator winding in the stator core and the stator core. And a rotor provided with a low coercivity permanent magnet and a high coercivity permanent magnet having a coercivity twice or more that of the low coercivity permanent magnet.

  According to the present invention, it is possible to perform variable speed operation in a wide range from low speed to high speed, and achieve high torque in the low speed rotation range, high output in the middle / high speed rotation range, improvement in efficiency, and improvement in reliability. A magnet-type rotating electrical machine can be provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  (First Embodiment) FIG. 1 is a sectional view of a rotor in a permanent magnet type rotating electric machine according to a first embodiment of the present invention. The rotor 1 of the present embodiment is composed of a rotor core 2, eight low coercivity permanent magnets 3, and eight high coercivity permanent magnets 4, and 5 is a cavity of the low coercivity permanent magnet 3. A certain first cavity 6 is a second cavity which is a cavity of the high coercive force permanent magnet 4, and 7 is a magnetic pole portion of the rotor core 2. The rotor core 2 is formed by laminating silicon steel plates, the low coercivity permanent magnet 3 is an alnico magnet or an FeCrCo magnet, and the high coercivity magnet 4 is an NdFeB magnet.

  FIG. 2 is a diagram showing the magnetic characteristics of an Alnico magnet (AlNiCo) as a low coercivity permanent magnet, an FeCrCo magnet as a low coercivity permanent magnet, and an NdFeB magnet as a high coercivity permanent magnet applied to this embodiment. . The coercive force of the alnico magnet (magnetic field at which the magnetic flux density becomes 0) is 60 to 120 kA / m, which is 1/15 to 1/8 of the coercive force of 950 kA / m of the NdFeB magnet. The coercive force of the FeCrCo magnet is about 60 kA / m, which is 1/15 of the coercive force of the NdFeB magnet of 950 kA / m. It can be seen that the alnico magnet and the FeCrCo magnet have a considerably low coercive force as compared with the NdFeB high coercive force magnet. In the present embodiment, the high coercive force permanent magnet 4 having a coercive force 8 to 15 times that of the low coercive force permanent magnet 3 is applied, whereby a rotating electrical machine having excellent characteristics can be obtained.

  The low coercivity permanent magnet 3 is embedded in the rotor core 2, and first cavities 5 are provided at both ends of the low coercivity permanent magnet 3. The low coercive force permanent magnet 3 is disposed along the radial direction of the rotor that coincides with the q axis serving as the central axis between the magnetic poles, and is magnetized in a direction perpendicular to the radial direction. The high coercivity permanent magnet 4 is embedded in the rotor core 2, and second cavities 6 are provided at both ends of the high coercivity permanent magnet 4. The high coercive force permanent magnet 4 is disposed substantially in the circumferential direction of the rotor 1 so as to be sandwiched between the two low coercive force permanent magnets 3 on the inner peripheral side of the rotor 1. The high coercive force permanent magnet 4 is magnetized in a direction substantially perpendicular to the circumferential direction of the rotor 1.

  The magnetic pole portion 7 of the rotor core 2 is formed so as to be surrounded by two low coercivity permanent magnets 3 and one high coercivity permanent magnet 4. As shown in FIG. 3, the central axis direction of the magnetic pole portion 7 of the rotor core 2 is the d axis, and the central axis direction between the magnetic poles is the q axis. Therefore, the low coercive force permanent magnet 3 is arranged in the q-axis direction which is the central axis between the magnetic poles, and the magnetization direction of the low coercive force permanent magnet 3 is 90 ° or −90 ° direction with respect to the q-axis. . In the adjacent low coercive force permanent magnets 3, the magnetic pole surfaces facing each other are made to have the same polarity. Further, the high coercive force permanent magnet 4 is arranged in a direction perpendicular to the d-axis which is the central axis of the magnetic pole part 7, and the magnetization direction is 0 ° or 180 ° with respect to the d-axis. In the adjacent high coercive force permanent magnets 4, the directions of the magnetic pole portions 7 are opposite to each other.

  A permanent magnet type rotating electrical machine 20 that employs the rotor 1 of the present embodiment configured as described above has a configuration shown in FIG. The coercive force of the FeCrCo magnet or alnico magnet, which is the low coercive permanent magnet 3 in the rotor 1, is as small as 60 to 120 kA / m, and these low coercive permanent magnets can be magnetized with a magnetic field of 200 to 300 kA / m. The coercive force of the NdFeB magnet which is the high coercive force permanent magnet 4 is as high as 950 kA / m and can be magnetized with a magnetic field of about 2400 kA / m. That is, the low coercive force permanent magnet 3 can be magnetized with a magnetic field about 1/10 that of the high coercive force permanent magnet 4. In the permanent magnet type rotating electrical machine 20 employing the rotor 1 of the present embodiment, a magnetic current is formed by passing a pulse-like current having a very short energization time (about 100 μs to 1 ms) through the stator winding, A magnetic field is applied to the low coercive force permanent magnet 3. When the magnetizing magnetic field is 250 kA / m, ideally, a sufficient magnetizing magnetic field acts on the low coercive force permanent magnet 3, and the high coercive force permanent magnet 4 does not undergo irreversible demagnetization due to magnetization.

  FIG. 3 is a diagram showing the magnetic flux of the permanent magnet in the initial state before applying the magnetizing magnetic field due to the d-axis current of this embodiment, and FIG. 4 is the magnetic flux of the permanent magnet when the magnetizing magnetic field is applied. FIG. The magnetic flux distribution in FIGS. 3 and 4 shows only one pole. The pulse current that forms the magnetizing magnetic field is the d-axis current component of the armature winding of the stator. In FIG. 4, the low coercivity permanent magnet is demagnetized, and the magnetic field due to the negative d-axis current is demagnetized for the permanent magnet, and the low coercivity permanent magnet 3 and the high coercivity permanent magnet from the magnetic pole center of the rotor 1. 4 acts in a direction almost opposite to the magnetization direction. In the permanent magnet type rotating electrical machine employing the rotor 1 of the present embodiment, the magnetic field due to the d-axis current is equivalent to two permanent magnets (two permanent magnets of N pole and S pole) in the high coercive force permanent magnet 4. The magnetic field acting on the high coercive force permanent magnet 4 is about half of the magnetic field acting on the low coercive force permanent magnet 3. Therefore, in the permanent magnet type rotating electrical machine employing the rotor 1 of the present embodiment, the magnetic field due to the d-axis current is likely to magnetize the low coercive force permanent magnet 3.

  FIG. 5 is a diagram showing the magnetic flux after magnetization of the rotor 1 of the present embodiment. The low coercive force permanent magnet 3 has a coercive force of about 1/10 that of the high coercive force permanent magnet 4, and a magnetic field twice as large as that of the high coercive force permanent magnet 4 acts on the low coercive force permanent magnet 3 as described above. Will do. In FIG. 5, the low coercive force permanent magnet 3 is magnetized in the direction of the magnetizing magnetic field and magnetized in the direction opposite to the initial magnetization direction in FIG. Then, the magnetization state of the low coercive force permanent magnet 3 can be adjusted by changing the magnitude of the d-axis current to change the strength of the magnetizing magnetic field. That is, three states are created: a state in which the magnetic force of the low coercivity permanent magnet 3 is reduced, a state in which the magnetic flux of the low coercivity permanent magnet 3 is zero, and a state in which the magnetic flux of the low coercivity permanent magnet 3 is reversed. Can do. On the other hand, the coercive force of the high coercive permanent magnet 4 is 10 times or more larger than that of the low coercive force permanent magnet 3, and the magnetizing magnetic field acting on the high coercive force permanent magnet 4 is 1 of the low coercive force permanent magnet 3 in this embodiment. / 2. Accordingly, the high coercivity permanent magnet 4 is in a reversible demagnetization state as long as the magnetic field is such that the low coercivity permanent magnet 3 is magnetized, and the high coercivity permanent magnet 4 can maintain the initial magnetic flux even after magnetization.

  With the configuration as described above, in the permanent magnet type rotating electrical machine 20 employing the rotor 1 of the present embodiment, the amount of interlinkage magnetic flux of the low coercive force permanent magnet 3 is increased from the maximum to 0 by the d-axis current of the rotor 1. The direction of magnetization can be changed in both forward and reverse directions. That is, assuming that the linkage flux of the high coercivity permanent magnet 4 is the positive direction, the linkage flux of the low coercivity permanent magnet 3 can be adjusted over a wide range from the maximum value in the positive direction to 0, and further to the maximum value in the reverse direction. it can. Therefore, in the rotor of the present embodiment, the total amount of interlinkage magnetic flux combining the low coercivity permanent magnet 3 and the high coercivity permanent magnet 4 is widened by magnetizing the low coercivity permanent magnet 3 with the d-axis current. Can be adjusted.

  For example, in the low speed region, the low coercive force permanent magnet 3 is magnetized by the d-axis current so that the maximum value is obtained in the same direction (initial state) as the interlinkage magnetic flux of the high coercive force permanent magnet 4, so that the torque by the permanent magnet is maximized. Therefore, the torque and output of the rotating electrical machine can be maximized.

  Further, in the middle / high speed range, as shown in FIG. 5, the magnetic flux of the low coercive force permanent magnet 3 is decreased and the total flux linkage is decreased, so that the voltage of the rotating electrical machine is lowered. Therefore, the rotational speed (frequency) can be further increased.

  Further, when the maximum speed is remarkably increased (when the variable speed range is further expanded, for example, when the variable speed range is 5 times or more of the base speed), the low coercive force permanent magnet 3 and the interlinkage magnetic flux of the high coercivity permanent magnet 4 Magnetization is performed in the opposite direction (the direction of magnetic flux is the state shown in FIG. 5 and the magnetization is maximized). The total interlinkage magnetic flux of the permanent magnet can be minimized by the difference of the interlinkage magnetic flux between the high coercivity permanent magnet 4 and the low coercivity permanent magnet 3, and the voltage of the rotating electrical machine can be minimized, so that the rotational speed (frequency) is maximized. Can be raised.

  According to the rotor 1 of the present embodiment, when this is adopted in the rotating electrical machine 20 shown in FIG. 18, a wide range of variable speed operation from low speed to high speed can be realized with high output, and the flux linkage is changed. Since the magnetizing current flows for only a very short time, the loss can be remarkably reduced, so that high efficiency can be achieved. In FIG. 18, 21 is a stator winding, and 22 is an air gap.

  When the rotating electrical machine generates an output, a q-axis current is caused to flow through the stator winding, thereby generating a torque by the magnetic action of the q-axis current and the magnetic flux of the permanent magnet of the rotor 1. At this time, a magnetic field is generated by the q-axis current. However, the low coercivity permanent magnet 3 is arranged in the q-axis direction, the magnetization direction is perpendicular to the q-axis direction, and the magnetization direction of the low coercivity permanent magnet 3 and the magnetic field due to the q-axis current are orthogonal to each other. Therefore, the influence of the magnetic field due to the q-axis current is small.

  Next, the operation of the first cavity 5 and the second cavity 6 will be described. The cavities 5 and 6 alleviate stress concentration and demagnetizing field on the rotor core 2 when centrifugal force by the permanent magnets acts on the rotor core 2. As shown in FIG. 1, by providing the cavities 5 and 6, the iron core can have a curved shape, and the stress is relieved. Further, the magnetic field due to the current concentrates on the corners of the permanent magnet and a demagnetizing field acts, and the corners are irreversibly demagnetized. However, in the rotor 1 of the present embodiment, the cavities 5 and 6 are formed at the magnet ends. Therefore, the demagnetizing field due to the current at the end of the permanent magnet is relaxed.

  The rotor 1 of the present embodiment as described above has the following operations and effects. If the interlinkage magnetic flux of the high coercivity permanent magnet 4 is in the positive direction, the interlinkage magnetic flux of the low coercivity permanent magnet 3 can be adjusted over a wide range from the maximum value in the positive direction to 0, and further to the maximum value in the reverse direction. Accordingly, by magnetizing the low coercive force permanent magnet 3 with the d-axis current, the total amount of interlinkage magnetic flux combining the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 can be adjusted over a wide range.

  The ability to adjust the total flux linkage of the permanent magnet over a wide range makes it possible to adjust the voltage of the rotating electrical machine that employs the rotor 1 over a wide range, and magnetization is performed with a pulse current in a very short time. Since it is not necessary to continue the flux-weakening current, the loss can be greatly reduced. Further, since it is not necessary to perform the flux-weakening control as in the prior art, iron loss due to harmonic magnetic flux does not occur. As described above, according to the rotor of the present embodiment, the rotating electrical machine that employs the rotor can perform variable speed operation over a wide range from low speed to high speed with high output, and high efficiency can be achieved.

  Further, with respect to the induced voltage by the permanent magnet, the low coercive force permanent magnet 3 can be magnetized by the d-axis current to reduce the total interlinkage magnetic flux of the permanent magnet, so that the inverter electronic components are not damaged by the induced voltage of the permanent magnet. Reliability can be improved. Furthermore, when the rotating electrical machine is rotated without load, the low coercive force permanent magnet 3 can be magnetized with the d-axis current to reduce the total interlinkage magnetic flux of the permanent magnet, thereby significantly reducing the induced voltage, There is almost no need to constantly apply a flux-weakening current for lowering the induced voltage, and overall efficiency can be improved. In the present embodiment, the case of 8 poles has been described, but the present invention can be similarly applied even if the number of poles is changed.

  (Second Embodiment) A rotating electrical machine 20 according to a second embodiment of the present invention uses a counter electromotive voltage generated by the high coercive force permanent magnet 4 of the rotor 1 at the maximum rotational speed of the rotor 1 to The withstand voltage of the inverter electronic component as a power source is set to be equal to or lower than the withstand voltage.

  The counter electromotive voltage generated by the permanent magnet increases in proportion to the rotational speed. When this counter electromotive voltage is applied to the electronic component of the inverter and exceeds the withstand voltage of the electronic component, the electronic component breaks down. Therefore, in the conventional permanent magnet type rotating electrical machine, the withstand voltage is limited at the time of design, the amount of magnetic flux of the permanent magnet is reduced, and the output and efficiency in the low speed range of the motor are reduced.

  In the rotating electrical machine 20 described above, when rotating at high speed, the magnetic field in the demagnetizing direction is applied to the permanent magnet by the negative d-axis current, and the magnetic flux of the low coercive force permanent magnet 3 can be reduced to near zero. The back electromotive force generated by the permanent magnet 3 can be made almost zero. And what is necessary is just to make the back electromotive voltage by the high coercive force permanent magnet 4 which cannot adjust magnetic flux amount into a withstand voltage or less at the maximum rotational speed. That is, the amount of magnetic flux of only the high coercive force permanent magnet 4 is reduced until it reaches the withstand voltage or less. On the other hand, at the time of low speed rotation, the amount of flux linkage between the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 magnetized so as to obtain the maximum amount of magnetic flux can be significantly increased as compared with the conventional permanent magnet type rotating electrical machine. .

  As described above, in the permanent magnet type rotating electrical machine 20 of the present embodiment, the back electromotive voltage during high speed rotation can be suppressed while maintaining high output and high efficiency during low speed rotation, and the reliability of the system including the inverter can be improved. Can be increased.

  (Third Embodiment) A permanent magnet type rotating electrical machine 20 according to a third embodiment of the present invention has a high coercive force permanent magnet in a state where the amount of magnetic flux of the permanent magnet is maximized when the maximum torque is generated. 4 is less than the maximum magnetic flux amount of the low coercive force permanent magnet 3.

  When the rotating electrical machine generates the maximum torque, the required current is reduced and the efficiency is increased by maximizing the amount of magnetic flux of the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 of the rotor. At the maximum rotation time, the amount of magnetic flux of the low coercive permanent magnet 3 can be reduced to near zero by the magnetizing magnetic field of the d-axis current, so that the counter electromotive voltage by the low coercive permanent magnet 3 can be made substantially zero. Then, the counter electromotive voltage generated by the high coercive force permanent magnet 4 in which the amount of magnetic flux cannot be adjusted may be made equal to or lower than the withstand voltage of the electronic components of the inverter at the maximum rotation speed. In the present embodiment, since the magnetic flux of the high coercive force permanent magnet 4 is made smaller than the magnetic flux of the low coercive force permanent magnet 3, the counter electromotive voltage per rotational speed by the high coercive force permanent magnet 4 is reduced, and even higher rotational speeds are achieved. Can be rotated.

  (Fourth Embodiment) FIG. 6 is a sectional view of a rotor 1 of a permanent magnet type rotating electric machine according to a fourth embodiment of the present invention. In addition, the same code | symbol is shown using the same or equivalent element as FIG. In FIG. 6, 1 is a rotor, 2 is a rotor core, 3 is a low coercivity permanent magnet, 4 is a high coercivity permanent magnet, 5 is a first cavity which is a cavity of the low coercivity permanent magnet 3, and 6 is a high coercivity. A second cavity which is a cavity of the permanent magnet 4, 7 is a magnetic pole part of the rotor core 2, and 8 is a recess part of the iron core.

  In the rotor 1 of the present embodiment, a low coercive force permanent magnet 3 is disposed in the radial direction of the rotor 1 that coincides with the q axis that is the central axis between the magnetic poles, and the iron core at the end of the low coercive force permanent magnet 3. The air gap side iron core in the vicinity of the end of the low coercive force permanent magnet 3 excluding the above is recessed from the outermost periphery of the rotor core 2 to form a recess 8.

  Next, the operation of the rotor 1 of the present embodiment will be described. A permanent magnet type rotating electrical machine 20 employing the rotor 1 has the same configuration as that shown in FIG. In such a rotating electric machine, the magnetic flux of the current in the d-axis direction (d-axis magnetic flux) crosses the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 of the rotor 1, and the permanent magnet passes through the air. Since it is almost equal to the magnetic susceptibility, the d-axis inductance is small. On the other hand, the magnetic flux in the q-axis direction flows through the magnetic pole portion 7 of the rotor core 2 along the longitudinal direction of the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4. Since the magnetic permeability of the magnetic pole portion 7 of the iron core is 1000 to 10,000 times that of the permanent magnet, if the rotor core 2 in the q-axis direction has no depression and the outer diameter of the rotor core 2 is uniform in the circumferential direction, the q-axis inductance Will grow. A q-axis current is supplied to generate torque by the magnetic action of the current and the magnetic flux. However, since the q-axis inductance is large, the voltage generated by the q-axis current increases. That is, as the q-axis inductance increases, the power factor deteriorates.

  In the present embodiment, the iron core on the air gap 22 side in the vicinity of the end of the low coercive force permanent magnet 3 is the recessed portion 8 that is recessed from the outermost periphery of the rotor core 2, so the magnetic flux that passes through the recessed portion 8 of the iron core 2. Decrease. That is, since the depression 8 is in the q-axis direction, the q-axis inductance can be reduced. Thereby, a power factor can be improved. Further, since the air gap length is equivalently increased in the vicinity of the end of the low coercive force permanent magnet 3 due to the recess 8 of the iron core 2, the average magnetic field in the vicinity of the end of the low coercive force permanent magnet 3 is reduced. Thus, the influence of the demagnetizing field on the low coercive force permanent magnet 3 due to the q-axis current necessary for generating torque can be reduced.

  Further, since only the iron core portion that holds the permanent magnet at the end of the low coercive force permanent magnet 3 is not recessed, the radial direction length of the low coercive force permanent magnet 3 can be made as long as possible. The permanent magnet volume can be increased in the child. That is, the amount of magnetic flux of the permanent magnet can be increased, and the output per rotor volume can be increased.

  (Fifth Embodiment) FIG. 7 is a sectional view of a rotor 1 of a permanent magnet type rotating electric machine according to a fifth embodiment of the present invention. In addition, the same code | symbol is shown using the same or equivalent element as FIG. 1, FIG. In FIG. 7, 1 is a rotor, 2 is a rotor core, 3 is a low coercive force permanent magnet, 4 is a high coercive force permanent magnet, 5 is a first cavity which is a cavity of the low coercive force permanent magnet 3, and 6 is a high coercive force. A second cavity which is a cavity of the magnetic permanent magnet 4, 7 indicates a magnetic pole part of the rotor core 2, and 8 indicates a recessed part of the rotor core 2.

  The low coercive force permanent magnet 3 is arranged in the radial direction that coincides with the q axis that is the central axis between the magnetic poles. Then, between the end of the low coercive force permanent magnet 3 and the center of the magnetic pole part 7 of the rotor core 2, the central part of the magnetic pole part 7 of the rotor core 2 becomes the outermost peripheral part of the rotor 1, and the magnetic pole part 7, the distance from the axial center of the rotor 1 to the outer periphery of the rotor core 2 is shortened from the central portion of the rotor 7 to the outer peripheral core portion of the end of the low coercive force permanent magnet 3.

  Next, the operation of the rotor 1 having the above configuration will be described. A permanent magnet type rotating electrical machine 20 employing the rotor 1 has the same configuration as that shown in FIG. In the rotating electrical machine 20, the magnetic flux of the current in the d-axis direction (d-axis magnetic flux) crosses the low coercivity permanent magnet 3 and the high coercivity permanent magnet 4 of the rotor 1, and the permanent magnet has air permeability. Therefore, the d-axis inductance is small. On the other hand, the magnetic flux in the q-axis direction flows along the longitudinal direction of the low coercivity permanent magnet 3 and the high coercivity permanent magnet 4 through the magnetic pole portion 7 of the rotor core. Since the magnetic core 7 has a magnetic permeability 1000 to 10000 times that of the magnet, the q-axis inductance increases if the rotor core in the q-axis direction has no depression and the outer diameter of the rotor core is uniform in the circumferential direction. A q-axis current is supplied to generate torque by the magnetic action of the current and the magnetic flux. However, since the q-axis inductance is large, the voltage generated by the q-axis current increases. That is, since the inductance is increased, the power factor is deteriorated.

  In the present embodiment, the distance from the central part of the outer periphery of the magnetic pole part 7 to the outer peripheral side core part of the end of the low coercive force permanent magnet 3 to the outer periphery of the rotor core 2 from the axial center of the rotor 1. Is a shape that shortens. Thereby, the air gap side iron core in the permanent magnet type rotating electrical machine adopting the rotor 1 has a shape in which the depression of the depression 8 becomes deeper from the center of the magnetic pole part 7 to the end of the low coercive force permanent magnet 3. . Since the air gap length is increased by the presence of the recess 8 having such a shape, the magnetic flux passing through the recess 8 decreases as the recess becomes deeper. That is, since the depression 8 is in the q-axis direction, the q-axis inductance can be reduced. As a result, the q-axis inductance can be reduced, and the power factor can be improved. In particular, since the depression is deepest in the iron core near the end of the low coercivity permanent magnet 3 on the q axis, the q axis inductance can be effectively reduced.

  Further, since the air gap length of the rotating electrical machine is the longest at the end of the low coercive force permanent magnet 3 due to the recess 8, the magnetic field in the vicinity of the end of the low coercive force permanent magnet 3 becomes low. Thereby, the influence of the demagnetizing field on the low coercive force due to the q-axis current for generating torque can be reduced.

  (Sixth Embodiment) FIG. 8 is a sectional view of a rotor 1 of a permanent magnet type rotating electric machine according to a sixth embodiment of the present invention. In addition, the same code | symbol is shown using the same or equivalent element as FIG.1, FIG.6, FIG.7. In FIG. 8, 1 is a rotor, 2 is a rotor core, 3 is a low coercivity permanent magnet, 4 is a high coercivity permanent magnet, 5 is a first cavity that is a cavity of the low coercivity permanent magnet 3, and 6 is a high coercivity. A second cavity which is a cavity of the magnetic permanent magnet 4, 7 is a magnetic pole part of the rotor core 2, 8 is a hollow part, and α indicates a central angle of an arc of the magnetic pole central part.

  The central part of the magnetic pole part 7 of the rotor core 2 is formed by an arc having the maximum radius of the rotor (the length from the rotor central axis to the outer periphery of the rotor is maximum), and the central angle α of the arc at the magnetic pole central part The angle is in the range of 90 to 140 degrees. In the rotor 1 in a region outside the central angle α, the outer periphery of the rotor core 2 is recessed on the inner peripheral side with respect to the arc of the maximum radius of the rotor 1, and this is a recess 8.

  A permanent magnet type rotating electrical machine 20 employing the rotor 1 has substantially the same configuration as that shown in FIG. In such a rotating electrical machine 20, when driving at a low or medium speed range below the maximum value of the power supply voltage, the magnetic flux of the permanent magnet is utilized to the maximum in order to obtain high efficiency. In the present embodiment, the central portion of the magnetic pole portion 7 of the rotor core 2 whose range is indicated by the central angle α is formed by an arc having the maximum radius of the rotor 1, so that the air gap length near the d-axis of the rotating electrical machine is Minimal. Therefore, the amount of interlinkage magnetic flux between the high coercivity permanent magnet 4 and the low coercivity permanent magnet 3 can be increased in the central portion of the magnetic pole near the d-axis having the central angle α.

  In the rotor 1 near the q-axis where the low coercive force permanent magnet 3 is present, the outer periphery of the rotor core 2 is recessed on the inner peripheral side of the arc having the maximum radius of the rotor 1. Becomes weaker. Therefore, when a q-axis current is applied to generate torque, it is possible to prevent the low coercive force permanent magnet 3 from being demagnetized by a magnetic field due to the q-axis current.

  With the above configuration, in the permanent magnet type rotating electrical machine 20 adopting the rotor 1 of the present embodiment, a high output and a high torque are ensured by increasing the amount of magnetic flux of the permanent magnet generated in the vicinity of the d-axis. The influence of the demagnetization of the low coercive force permanent magnet 3 due to the q-axis current can be greatly reduced.

  FIG. 9 is a diagram showing a change in torque with respect to the magnetic pole center angle α of the permanent magnet type rotating electrical machine to which the present embodiment is applied. It can be seen that a large torque can be obtained when the central angle α of the arc at the center of the magnetic pole is in the range of 90 to 140 degrees in electrical angle.

  (Seventh Embodiment) A permanent magnet type rotating electrical machine 20 according to a seventh embodiment of the present invention has the configuration shown in FIG. It is characterized by being made thinner than the thickness in the magnetization direction. The strength of the magnetic field that magnetizes the permanent magnet is almost proportional to the thickness in the magnetization direction. Therefore, by making the magnetization direction thickness of the low coercivity permanent magnet 3 thinner than the magnetization direction thickness of the high coercivity permanent magnet 4, the magnetic field for magnetizing the low coercivity permanent magnet 3 can be lowered and the magnetization current can be reduced. .

  In general, the temperature characteristics of the high coercive force permanent magnet 4 become worse as the product of high magnetic energy is increased, and the coercive force is reduced at a high temperature state of 100 ° C. or higher, and the permanent magnet is irreversibly demagnetized with a smaller demagnetizing field. . However, in the present embodiment, the magnetic field for magnetizing the low coercive force permanent magnet 3 can be reduced, so that the high coercive force permanent magnet 4 is irreversibly demagnetized even if the magnetizing magnetic field acts in a high temperature state. Can be prevented.

  (Eighth Embodiment) FIG. 10 is a sectional view of a rotor 1 of a permanent magnet type rotating electric machine according to an eighth embodiment of the present invention. In addition, the same code | symbol is shown using the same or equivalent element as FIG. 1, FIG. In FIG. 10, 1 is a rotor, 2 is a rotor core, 3 is a low coercivity permanent magnet, 4 is a high coercivity permanent magnet, 5 is a first cavity which is a cavity of the low coercivity permanent magnet 3, and 6 is a high coercivity. A second cavity which is a cavity of the magnetic permanent magnet 4, 7 is a magnetic pole part of the rotor core 2, and 8 is a recess part of the rotor core 2. The rotor 1 of the present embodiment has a shape in which the thickness in the magnetization direction of the low coercive force permanent magnet 3 is not constant, and the thickness gradually increases toward the outer peripheral side of the rotor 1.

  When a magnetizing magnetic field is applied to the low coercive force permanent magnet 3, the magnetizing magnetic field acting on the low coercive force permanent magnet 3 in the rotor 1 is not uniformly distributed, and the strength of the magnetic field is permanent magnet. Biased in. If the magnetic field is partially biased, it becomes difficult to adjust the amount of magnetic flux of the low coercive force permanent magnet 3 by the amount of magnetizing current. Further, since the amount of magnetic flux of the permanent magnet varies depending on the fluctuation of the magnetizing magnetic field and the temperature state at the time of driving, it becomes difficult to obtain reproducibility within a range of variations with a small amount of magnetic flux when magnetized. Therefore, the present embodiment applies the characteristic that the magnetizing force necessary for the magnetization of the permanent magnet greatly changes depending on the thickness in the magnetization direction of the permanent magnet.

  Therefore, in the rotor 1 of the present embodiment, the magnetization direction thickness of the low coercive force permanent magnet 3 is not constant, but the thickness is changed. Therefore, the amount of magnetic flux generated in the permanent magnet portion of each thickness when the magnetizing magnetic field is applied can be changed, and the strength of the magnetizing magnetic field can be largely dependent on the influence of the thickness of the permanent magnet. This makes it possible to reduce the influence of fluctuations in external conditions such as bias due to magnetic field concentration and fluctuations in the magnetizing magnetic field, facilitating adjustment of the amount of magnetic flux with respect to the magnetizing current, and variations in the amount of magnetic flux due to fluctuations in external conditions. Can be reduced.

  FIG. 11 is a longitudinal sectional view of the low coercive force permanent magnet 3 of the present embodiment. In FIG. 11, the thickness in the magnetization direction of the low coercive force permanent magnet 3 is set to be different in a stepwise manner. With this shape, the change width of the amount of magnetic flux of the permanent magnet can be increased stepwise in the same manner as the change width of the thickness of the permanent magnet. Therefore, the influence on the magnetic flux amount due to the change width of the permanent magnet thickness can be made much larger than the fluctuation width of the magnetizing magnetic field due to disturbances and atmospheric conditions. That is, when the amount of magnetic flux is changed by magnetizing the low coercive force permanent magnet 3, variation in the amount of magnetic flux due to fluctuations in the magnetizing magnetic field can be reduced, and the reproducibility of the amount of magnetic flux of the low coercive force permanent magnet 3 at the same magnetization current. Can also be obtained.

  (Ninth Embodiment) FIG. 12 is a sectional view of a rotor 1 of a permanent magnet type rotating electric machine according to a ninth embodiment of the present invention. In addition, the same code | symbol is shown using the same code | symbol to the element which is the same as that of FIG. 1, FIG. In FIG. 12, 1 is a rotor, 2 is a rotor core, 3 is a low coercive force permanent magnet, 4 is a high coercive force permanent magnet, 5 is a first cavity which is a cavity of the low coercive force permanent magnet 3, and 6 is a high coercive force. A second cavity which is a cavity of the magnetic permanent magnet 4, 7 indicates a magnetic pole part of the rotor core 2, and 8 indicates a recessed part of the rotor core 2.

  In the present embodiment, the low coercive force permanent magnet 3 has a tapered shape in which the thickness in the magnetization direction becomes thinner toward the outer peripheral side of the rotor 1. Thus, by reducing the thickness of the low coercive force permanent magnet 3 toward the outer peripheral side of the rotor 1, the centrifugal force of the low coercive force permanent magnet 3 is received on the rotor core surface in contact with the low coercive force permanent magnet 3. Thus, the rotor core 2 can hold the low coercive force permanent magnet 3. Moreover, even if the dimensional accuracy of the magnetization direction thickness of the low coercive force permanent magnet 3 is rough, the permanent magnet can be fixed by the low coercive force permanent magnet 3 coming into contact with the rotor core 2 at a radial position corresponding to the size. When this embodiment is applied together with a method for producing a permanent magnet by molding, it becomes possible to apply a permanent magnet with poor dimensional accuracy after molding, which is also a drawback of mold production, and mass production is possible by producing a mold with a low coercive force permanent magnet. Will improve.

  Further, the following actions and effects can be obtained simultaneously with the retention of the low coercive force permanent magnet 3 and the improvement of mass productivity. When the thickness of the low coercive force permanent magnet 3 is constant, the low coercive force permanent magnet 3 is biased in the magnetizing magnetic field, and the magnetic flux amount of only a part of the low coercive force permanent magnet is biased, and the magnetic field There is a problem that the change width of the magnetic flux amount of the permanent magnet with respect to the change width is steep. The magnetizing magnetic field of the permanent magnet greatly depends on the thickness of the permanent magnet, and when magnetized, the amount of magnetic flux of the permanent magnet in that portion varies greatly depending on the thickness. In the present embodiment, since the thickness of the low coercive force permanent magnet 3 is different, the corresponding partial magnetic flux amount greatly changes in the magnetizing magnetic field corresponding to each thickness. That is, the strength of the magnetic field at which the magnetic flux of the permanent magnet changes greatly depends on the thickness of the permanent magnet. Thereby, the change width of the magnetization magnetic field with respect to the change width of the magnetic flux amount of the low coercive force permanent magnet 3 can be widened. In other words, the amount of magnetic flux of an arbitrary permanent magnet can be easily adjusted by adjusting the magnetizing current in a rotating electrical machine, and the variation in the amount of magnetic flux of a low-coercivity permanent magnet when magnetization is repeated (good reproduction) ), The fluctuation width of the magnetic flux amount of the permanent magnet at the time of magnetization due to the fluctuation of the surrounding conditions such as the fluctuation of the magnetizing current and the temperature.

  (Tenth Embodiment) FIG. 13 is a sectional view of a rotor 1 of a permanent magnet type rotating electric machine according to a tenth embodiment of the present invention. In addition, the same code | symbol is shown for the element which is the same as that of FIG. 1, FIG. 6-FIG. 8, FIG. 10, FIG. In FIG. 13, 1 is a rotor, 2 is a rotor core, 3 is a low coercive force permanent magnet, 4 is a high coercive force permanent magnet, 5 is a first cavity which is a cavity of the low coercive force permanent magnet 3, and 6 is a high coercive force. A second cavity which is a cavity of the magnetic permanent magnet 4, 7 is a magnetic pole part of the rotor core 2, 8 is a recessed part of the rotor core 2, 9 is a magnetic barrier, and 10 is a protrusion.

  In the rotor 1 of the present embodiment, the magnetic force that is longer in the circumferential direction of the rotor than the thickness in the magnetization direction of the low coercive force permanent magnet 3 on the rotor core 2 near the air gap side end of the low coercive force permanent magnet 3. A barrier 9 is provided. The magnetic barrier 9 is a hole and there will be air. Further, a protrusion 10 is provided on the outer peripheral side (air gap side) end of the low coercive force permanent magnet 3. The protrusion 10 receives the centrifugal force of the low coercive force permanent magnet 3 and holds the permanent magnet.

  When a q-axis current is applied to generate a torque for a permanent magnet type rotating electrical machine 20 as shown in FIG. 18 employing the rotor 1 of the present embodiment, the low coercive force permanent magnet 3 on the q axis. Produces a magnetic field due to the q-axis current. In the rotor 1 of the present embodiment, since the magnetic barrier 9 is provided in the vicinity of the end of the low coercive permanent magnet 3, the q axis acting on the end of the low coercive permanent magnet 3 by the air layer of the magnetic barrier 9. The magnetic field of the current can be reduced, thereby suppressing the demagnetization and the magnetization of the low coercive force permanent magnet 3 due to the q-axis current. Further, since the magnetic barrier 9 is longer in the circumferential direction than the magnetization direction thickness of the low coercive force permanent magnet 3, the magnetic field due to the q axis current concentrated on the corner of the end of the low coercive force permanent magnet 3 can be relaxed, and the q axis current It is possible to prevent demagnetization and magnetization of the low coercive force permanent magnet 3 due to the wraparound of the magnetic field. Furthermore, since the magnetic barrier 9 is long in the circumferential direction of the rotor around the q axis, the magnetic resistance in the q axis direction is increased, and the amount of magnetic flux due to the q axis current can be reduced. Therefore, since the q-axis inductance is small, the power factor can be increased.

  (Eleventh Embodiment) FIG. 14 is a sectional view of a rotor 1 of a permanent magnet type rotating electric machine according to an eleventh embodiment of the present invention. In addition, the same code | symbol is shown using the same code | symbol to the element which is the same as that of FIG. 1, FIG. 6-FIG. 8, FIG. 10, FIG. In FIG. 14, 1 is a rotor, 2 is a rotor core, 3 is a low coercivity permanent magnet, 4 is a high coercivity permanent magnet, 5 is a first cavity which is a cavity of the low coercivity permanent magnet 3, and 6 is a high coercivity. A second cavity which is a cavity of the magnetic permanent magnet 4, 7 is a magnetic pole part of the rotor core 2, 8 is a recessed part, 9 is a magnetic barrier, 10 is a protrusion, and 11 is a slit.

  In the present embodiment, the slit 11 is provided at a position coincident with the central axis of the d-axis in the magnetic pole portion 7 of the iron core between the adjacent low coercive force permanent magnets 3. Since the slit 11 is on the d-axis, it does not become a magnetic barrier for d-axis magnetic flux but a magnetic barrier for q-axis magnetic flux. Therefore, the q-axis magnetic flux can be reduced while the influence on the magnetic flux of the permanent magnet distributed around the d-axis is small. That is, the power factor can be improved while maintaining the torque by the permanent magnet.

  (Twelfth Embodiment) FIG. 15 is a sectional view of a rotor 1 of a permanent magnet type rotating electric machine according to a twelfth embodiment of the present invention. 1, 6 to 8, 10, and 12 to 14, the same or equivalent elements are denoted by the same reference numerals. In FIG. 15, 1 is a rotor, 2 is a rotor core, 3A is a high coercivity permanent magnet, 4A is a low coercivity permanent magnet, 5 is a first cavity which is a cavity of the high coercivity permanent magnet 3A, and 6 is a low coercivity. A second cavity which is a cavity of the magnetic permanent magnet 4 </ b> A, 7 is a magnetic pole part of the rotor core 2, and 8 is a recessed part of the rotor core 2.

  As in the other embodiments, the rotor 1 of the present embodiment is arranged at the center of the stator of the permanent magnet type rotating electrical machine 20 as shown in FIG. 18 and is rotated by the magnetic field generated by the stator coil. Drive.

  Unlike the first to eleventh embodiments, the permanent magnet type rotating electrical machine of the present embodiment has a high coercive force permanent magnet 3 </ b> A arranged in the radial direction of the rotor 1, and on the inner peripheral side of the rotor core 2. The low coercive force permanent magnet 4A is arranged in parallel with the circumferential direction.

  Regarding the magnetic field due to the stator current acting on the high coercivity permanent magnet 3 </ b> A arranged in the radial direction, the magnetic path is as follows. Stator core → air gap 20 → rotor magnetic pole 7 → radially positioned high coercivity permanent magnet 3A (transverse) → adjacent rotor magnetic pole 7 → stator core. On the other hand, the magnetic path due to the stator current acting on the low coercive force permanent magnet 4 </ b> A arranged in the circumferential direction on the inner peripheral side has the following magnetic path. Stator core → air gap 20 → rotor magnetic pole 7 → low coercive force permanent magnet 4A (transverse) located in the circumferential direction → the innermost peripheral part of the rotor core 2 → the innermost peripheral part of the adjacent rotor core 2 → Low coercive force permanent magnet 4A (transverse) located in the adjacent circumferential direction → adjacent rotor magnetic pole 7 → stator core.

  Therefore, the magnetic field due to the current acts on the two low coercivity permanent magnets 4A arranged in the circumferential direction, and acts on the single high coercivity permanent magnet 3A arranged in the radial direction. Accordingly, if the thickness of the high coercivity permanent magnet 3A and the thickness of the low coercivity permanent magnet 4A are the same, the magnetic field generated by the current acting on the high coercivity permanent magnet 3A arranged in the radial direction is the low coercivity permanent magnet arranged in the circumferential direction. It is twice as strong as the magnet 4A.

  In a rotating electrical machine with high output by increasing the specific electrical load (ampere turn per unit circumference) by performing water cooling or oil cooling on the stator, the magnetic field due to the load current is large, and the strong magnetic field due to this load current Partial demagnetization occurs. Even in the case of such a high power density rotating electric machine, in the permanent magnet type rotating electric machine according to the present embodiment, the low coercive force permanent magnet 4A that is easily affected by a magnetic field is arranged on the inner peripheral side, thereby partially The effect of demagnetization can be reduced. Thereby, according to the permanent magnet type rotating electrical machine of the present embodiment, the amount of interlinkage magnetic flux of the permanent magnetic flux can be varied by magnetizing the permanent magnet with the d-axis current of the rotor 1, and at the same time, High output can be maintained by suppressing characteristic changes.

  In the present embodiment, the core recess 8 can be formed as necessary, and the outer peripheral surface of the rotor core 2 as in the first embodiment shown in FIG. May have a perfect circular cross section, or may have the shape shown in FIGS. Further, the first cavity 5 may have the shape shown in FIGS. Further, the high coercive force permanent magnet 3 </ b> A serving as the outer peripheral side permanent magnet can be formed in the shape of FIG. 11, FIG. 12, or FIG. 13.

  (Thirteenth Embodiment) FIG. 16 is a sectional view of a rotor 1 of a permanent magnet type rotating electric machine according to a thirteenth embodiment of the present invention. 1, 6 to 8, 10, and 12 to 15, the same or equivalent elements are denoted by the same reference numerals. In the permanent magnet type rotating electrical machine of the present embodiment, a high coercive force permanent magnet 3B is disposed as a radial permanent magnet of the rotor core 2, and a high coercive force is also provided as a circumferential permanent magnet on the inner peripheral side of the rotor core 2. The permanent magnet 4B is arranged. Other configurations are the same as those of the twelfth embodiment shown in FIG.

  The permanent magnets 3B and 4B have a magnetization direction thickness that can change the magnetization state by a magnetization magnetic field generated by a d-axis current. Alternatively, only the radial high coercivity permanent magnet 3 </ b> B or the circumferential high coercivity permanent magnet 4 </ b> B has a thickness in the magnetization direction in which the magnetization state can be changed by the magnetization magnetic field generated by the d-axis current.

  In the permanent magnet type rotating electrical machine of the present embodiment, high coercive force permanent magnets are arranged both in the radial permanent magnet 3B of the rotor core 2 and in the circumferential permanent magnet 4B on the inner peripheral side of the rotor core 2. Therefore, stable characteristics against disturbance such as a magnetic field due to load current can be obtained.

  By cooling the stator with water or oil, the rotating electrical machine can increase the specific electrical load (ampere turn per unit circumference) and increase the output. However, since the magnetic field due to the load current is increased, the surrounding permanent magnet is also partially demagnetized due to the strong magnetic field due to the load current. In the case of such a high power density rotating electrical machine, by applying a high coercive force permanent magnet, the influence of the magnetic field due to the load current is reduced, and stable permanent magnet characteristics can be obtained. However, the permanent magnet has a thickness that can be sufficiently magnetized even by a magnetizing magnetic field generated by a d-axis current. For example, the radial permanent magnet 3B is thinner than the circumferential permanent magnet 4B so that the magnetization amount of the permanent magnet can be adjusted with a smaller magnetizing magnetic field (less d-axis current).

  Even in the present embodiment, the core recess 8 can be formed as necessary, and the outer peripheral surface of the rotor core 2 as in the first embodiment shown in FIG. May have a perfect circular cross section, or may have the shape shown in FIGS. Further, the first cavity 5 may have the shape shown in FIGS. Further, the high coercive force permanent magnet 3 </ b> A serving as the outer peripheral side permanent magnet can be formed in the shape of FIG. 11, FIG. 12, or FIG. 13.

  (Fourteenth Embodiment) A permanent magnet type rotating electric machine according to a fourteenth embodiment of the present invention will be described with reference to FIG. In addition, the same code | symbol is shown using the same code | symbol to the element which is the same as that of FIG. 1, FIG. 6 ~ FIG. 8, FIG. 10, FIG.

  The feature of this embodiment is that a slit 12 for preventing demagnetization by a permanent magnet is provided in the rotor core 2 as shown in FIG. A low coercivity permanent magnet 3 is arranged in the radial direction on the outer peripheral side of the rotor core 2, and a high coercivity permanent magnet 4 is arranged in the circumferential direction on the inner peripheral side of the rotor core 2. A slit 12 for preventing a demagnetizing field by a permanent magnet is provided in the magnetic pole portion 7 of the rotor core 2 so that the slit 12 blocks the magnetic flux by the low coercive force permanent magnet 3 and the magnetic flux by the high coercive force permanent magnet 4. Yes.

  Since the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 are arranged in the same magnetic core, the demagnetizing field acts on each other, but in the present embodiment, the slits 12 are interposed between each other, It can be made small enough not to be affected by the demagnetizing field due to other permanent magnets. Therefore, the low coercive force permanent magnet 3 is not demagnetized by a demagnetizing field caused by the high coercive force permanent magnet 4 and a load current due to the load current. Further, the increase / decrease of the magnetic flux of the low coercive force permanent magnet 3 due to the magnetizing magnetic field of the d-axis current is not affected by the high coercive force permanent magnet 4 and is easy. The same effect can be obtained even if the permanent magnets 3 and 4 in the rotor core 2 are all high coercivity permanent magnets.

  (Fifteenth Embodiment) In each of the first to fourteenth embodiments, the magnetization direction of the low coercive force permanent magnet is reversed in both directions by the magnetic field generated by the current of the stator winding. it can.

  The amount of magnetic flux of the permanent magnets arranged in the radial direction or circumferential direction of the rotor 1 is reduced by the magnetizing magnetic field generated by the d-axis current. If the magnetic flux amount of the permanent magnet to be magnetized becomes zero only by reducing the magnetic flux, the total interlinkage magnetic flux amount by all the permanent magnets is minimized. Therefore, in the present embodiment, by further magnetizing the magnetized permanent magnet in the reverse direction, it is subtracted from the magnetic flux of the other permanent magnet, and the total flux linkage by all the permanent magnets can be further reduced. Ideally, the total flux linkage can be reduced to zero. As a result, even when driven at high speed in a no-load state, the induced voltage is extremely small, and a rotating electrical machine with little iron loss can be obtained.

  (Sixteenth Embodiment) The sixteenth embodiment of the present invention is the permanent magnet type rotating electrical machine 20 having the configuration as shown in FIG. When rotating at a high speed exceeding 1, the low coercive force permanent magnet 3 is magnetized by using a magnetic field formed by the current of the stator winding so that the interlinkage magnetic flux by the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 is reduced. The total flux linkage of the magnet is adjusted. The low coercive force permanent magnet 3 used in the present embodiment uses an FeCrCo magnet or an alnico magnet, and the high coercive force permanent magnet 4 uses an NdFeB magnet.

  In the permanent magnet type rotating electrical machine, since the amount of magnetic flux of the permanent magnet is constant, the voltage due to the interlinkage magnetic flux of the permanent magnet increases in proportion to the rotational speed of the rotor 1. Therefore, when the power supply voltage has an upper limit and the rotating electrical machine is operated in a wide range from a low speed to a high speed, it cannot be operated at a higher rotational speed when the upper limit value of the power supply voltage is reached. Therefore, the magnitude of the voltage of the rotating electrical machine is determined by the winding inductance and the interlinkage magnetic flux generated by the permanent magnet. Therefore, the amount of interlinkage magnetic flux of the permanent magnet is reduced in order to suppress the voltage increase during high-speed rotation. It is possible.

  The FeCrCo magnet and the alnico magnet which are the low coercive force permanent magnets 3 used in the present embodiment have a small coercive force of 60 to 200 kA / m and can be magnetized with a magnetic field of 200 to 300 kA / m. The NdFeB magnet which is the high coercive force permanent magnet 4 has a high coercive force of 950 kA / m and can be magnetized by a magnetic field of 2400 kA / m. Therefore, the low coercive force permanent magnet 3 can be magnetized with a magnetic field of about 1/10 that of the high coercive force permanent magnet 4. In the present embodiment, a magnetic field is formed by applying a pulsed current whose energization time is extremely short (about 100 μs to 1 ms) to the stator winding 21, and the magnetic field is applied to the low coercive force permanent magnet 3. When the magnetizing magnetic field is 250 kA / m, ideally, a sufficient magnetic field acts on the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 does not undergo irreversible demagnetization due to magnetization.

  In the initial state, the interlinkage magnetic flux of the low coercive force permanent magnet 3 and the interlinkage magnetic flux of the high coercivity permanent magnet 4 are in a state of increasing in addition in the same direction. Then, when the rotating electrical machine voltage is near the maximum voltage of the power supply or at high speed rotation exceeding the maximum voltage, a negative d-axis current is applied in a pulsed manner to generate a low coercive force permanent magnet as shown in FIG. A magnetic field in the direction opposite to the magnetization direction of 3 is applied. The low coercivity permanent magnet 3 is demagnetized or magnetized in the reverse direction as shown in FIG. Thereby, the flux linkage which is the sum of the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 can be reduced. Since the amount of magnetic flux linkage decreases, the voltage of the rotating electrical machine becomes lower than the upper limit of the power supply voltage, and it is possible to operate at higher speed until the upper limit value of the power supply voltage is reached.

  The voltage can be adjusted by changing the magnetization state of the low coercive force permanent magnet 3 by changing the magnitude of the d-axis current to change the strength of the magnetizing magnetic field. At this time, the low coercivity permanent magnet 3 has three states: a state in which the magnetic force is reduced, a state in which the magnetic flux of the low coercivity permanent magnet is zero, and a state in which the magnetic flux of the low coercivity permanent magnet is reversed. can do.

  On the other hand, the high coercive force permanent magnet 4 has a coercive force 10 times or more larger than that of the low coercive force permanent magnet 3, and the magnetizing magnetic field acting on the high coercive force permanent magnet 4 is 1/0 of that of the low coercive force permanent magnet 3 in this embodiment. 2 Therefore, if the magnetic field is sufficient to magnetize the low coercivity permanent magnet 3, the high coercivity permanent magnet 4 is in a reversible demagnetization state, and the high coercivity permanent magnet can maintain the initial magnetic flux even after magnetization. .

  When generating an output, a q-axis current is caused to flow through the stator winding, thereby generating a torque by the magnetic action of the q-axis current and the magnetic flux of the permanent magnet. At this time, a magnetic field due to the q-axis current is generated. However, since the low coercivity permanent magnet 3 is arranged in the q-axis direction and the magnetization direction is perpendicular to the q-axis direction, the magnetization direction of the low coercivity permanent magnet and the magnetic field due to the q-axis current are orthogonal to each other. become. Therefore, the influence of the magnetic field due to the q-axis current is small.

  (Seventeenth Embodiment) A seventeenth embodiment of the present invention is a permanent magnet type rotating electrical machine having a configuration as shown in FIG. The low coercivity permanent magnet 3 is magnetized by the magnetic field formed by the current of the stator winding so that the interlinkage magnetic flux by the low coercivity permanent magnet 3 and the high coercivity permanent magnet 4 is increased, and the voltage of the rotating electrical machine During high-speed rotation near or exceeding the maximum voltage, the low coercivity permanent magnet 3 is magnetized by the magnetic field formed by the current of the stator winding so that the linkage flux between the low coercivity permanent magnet 3 and the high coercivity permanent magnet 4 is reduced. The interlinkage magnetic flux amount of the permanent magnet is adjusted.

  The low coercive force permanent magnet 3 used in the present embodiment uses an FeCrCo magnet or an alnico magnet, and the high coercive force permanent magnet 4 uses an NdFeB magnet. The FeCrCo magnet and alnico magnet, which are the low coercivity permanent magnets 3 used in the present embodiment, have a small coercive force of 60 to 200 kA / m and can be magnetized with a magnetic field of 200 to 300 kA / m. The NdFeB magnet which is the high coercive force permanent magnet 4 has a high coercive force of 950 kA / m and can be magnetized by a magnetic field of 2400 kA / m. Therefore, the low coercive force permanent magnet 3 can be magnetized with a magnetic field 1/10 that of the high coercive force permanent magnet 4. In the present embodiment, a magnetic field is formed by applying a pulsed current whose energization time is extremely short (about 100 μs to 1 ms) to the stator winding, and the magnetic field is applied to the low coercive force permanent magnet 3. When the magnetizing magnetic field is 250 kA / m, ideally, a sufficient magnetic field acts on the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 does not undergo irreversible demagnetization due to magnetization.

  When there is a margin in the voltage of the rotating electrical machine with respect to the maximum value of the power supply voltage, such as during low-speed rotation, a magnetizing magnetic field is generated by a positive d-axis current, and the low coercive force permanent magnet 3 is magnetized. The low coercive force permanent magnet 3 is set in the same direction as the interlinkage magnetic flux of the high coercive force permanent magnet 4 and is magnetized in an increasing direction by addition. Since torque is generated by the interlinkage magnetic flux and q-axis current of the permanent magnet, the torque can be increased by increasing the interlinkage magnetic flux of the permanent magnet.

  At the time of high-speed rotation where the voltage of the rotating electrical machine is close to or exceeds the maximum voltage of the power supply, the stator windings are set so that the interlinkage magnetic flux by the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 is reduced as in the sixteenth embodiment The low coercive force permanent magnet 3 is magnetized by the magnetic field generated by the current of the current to adjust the amount of flux linkage of the permanent magnet. Since the amount of flux linkage decreases, the voltage of the rotating electrical machine becomes lower than the maximum value of the power supply voltage, and it is possible to operate at higher speed until the maximum value of the power supply voltage is reached.

  As described above, a magnetic field is generated using the d-axis current as a magnetizing current, and the amount of interlinkage magnetic flux of the low coercive force permanent magnet 3 is adjusted by the d-axis current, thereby generating high torque at low speed and high speed and high speed rotation. A rotating electrical machine that can be driven and can be operated in a wide range of variable speeds from low speed to high speed with high output is obtained.

  (Eighteenth Embodiment) The twentieth embodiment of the present invention is a low magnetic field generated by the d-axis current of the stator winding 21 in the permanent magnet type rotating electrical machine 20 having the configuration shown in FIG. The amount of magnetic flux of the coercive force permanent magnet 3 is adjusted, and the amount of flux linkage between the low coercive force permanent magnet 3 and the high coercive force permanent magnet 4 is set to zero.

  The low coercive force permanent magnet 3 used in the present embodiment uses an FeCrCo magnet or an alnico magnet, and the high coercive force permanent magnet 4 uses an NdFeB magnet. The FeCrCo magnet and the alnico magnet which are the low coercive force permanent magnets 3 used in the present embodiment have a small coercive force of 60 to 200 kA / m and can be magnetized with a magnetic field of 200 to 300 kA / m. The NdFeB magnet which is the high coercive force permanent magnet 4 has a high coercive force of 950 kA / m and can be magnetized by a magnetic field of 2400 kA / m. Therefore, the low coercive force permanent magnet 3 can be magnetized with a magnetic field of about 1/10 that of the high coercive force permanent magnet 4.

  In the present embodiment, a magnetic field is formed by applying a pulsed current whose energization time is extremely short (about 100 μs to 1 ms) to the stator winding, and the magnetic field is applied to the low coercive force permanent magnet 3. If the magnetizing magnetic field is 250 kA / m, ideally a sufficient magnetic field acts on the low coercive force permanent magnet 3 to be magnetized, but the high coercive force permanent magnet 4 is not magnetized and the pulse current becomes zero. Then, it changes reversibly and returns to the original state. That is, the amount of flux linkage of the low coercivity permanent magnet 3 is adjusted, and the amount of flux linkage of the high coercivity permanent magnet 4 is constant.

  Then, the amount of magnetic flux of the low coercivity permanent magnet 3 is adjusted by the magnetizing magnetic field generated by the d-axis current, and the amount of flux linkage between the low coercivity permanent magnet 3 and the high coercivity permanent magnet 4 is set to zero. Since the interlinkage magnetic flux by the permanent magnet is 0, when the rotating electrical machine is rotated from the outside, iron loss due to the interlinkage magnetic flux of the permanent magnet does not occur. Further, when a conventional permanent magnet motor is applied to a hybrid vehicle or a train drive system, the induced voltage by the permanent magnet exceeds the withstand voltage of the electronic components of the inverter during high-speed rotation, and the electronic components are damaged. In addition, in order to keep the motor voltage below the power supply voltage, it is necessary to constantly weaken the flux current in the high-speed rotation region even when there is no load, and the overall efficiency of the motor deteriorates.

  When the permanent magnet type rotating electrical machine of the present embodiment is applied to a hybrid vehicle or a train drive system, the interlinkage magnetic flux by the permanent magnet can be adjusted to 0, so that the electronic components of the inverter are damaged by the induced voltage of the permanent magnet. In other words, it is not necessary to keep the magnetic flux current constantly flowing without any load in the high-speed rotation region.

  Therefore, if the rotating electrical machine of the present embodiment is applied, the reliability of the applied system can be improved and at the same time high efficiency can be obtained.

  (Nineteenth Embodiment) In the nineteenth embodiment of the present invention, the permanent magnet type rotating electrical machine 20 having the configuration shown in FIG. 18 is magnetized with a d-axis current to obtain the maximum amount of magnetic flux. The amount of magnetic flux generated by the low coercive force permanent magnet 3 and the amount of magnetic flux generated by the high coercive force permanent magnet 4 are the same.

  The low coercivity permanent magnet 3 of the rotor 1 used in the present embodiment uses an FeCrCo magnet or an alnico magnet, and the high coercivity permanent magnet 4 uses an NdFeB magnet.

  The FeCrCo magnet and the alnico magnet which are the low coercive force permanent magnets 3 used in the present embodiment have a small coercive force of 60 to 200 kA / m and can be magnetized with a magnetic field of 200 to 300 kA / m. The NdFeB magnet which is the high coercive force permanent magnet 4 has a high coercive force of 950 kA / m and can be magnetized by a magnetic field of 2400 kA / m. Therefore, the low coercive force permanent magnet 3 can be magnetized with a magnetic field 1/10 that of the high coercive force permanent magnet 4.

  In the present embodiment, a magnetic field is formed by applying a pulsed current whose energization time is extremely short (about 100 μs to 1 ms) to the stator winding, and the magnetic field is applied to the low coercive force permanent magnet 3. If the magnetizing magnetic field is 250 kA / m, ideally a sufficient magnetic field acts on the low coercive force permanent magnet 3 to be magnetized, but the high coercive force permanent magnet 4 is not magnetized and the pulse current becomes zero. Then, it changes reversibly and returns to the original state. That is, the amount of flux linkage of the low coercivity permanent magnet 3 is adjusted, and the amount of flux linkage of the high coercivity permanent magnet 4 is constant.

  As described in the eighteenth embodiment, if the amount of flux linkage of the permanent magnet can be reduced to 0, the reliability of the application system of the rotating electrical machine is improved, and at the same time, there is a great effect of obtaining high efficiency. Thus, the amount of magnetic flux of the low coercivity permanent magnet 3 is adjusted by the magnetizing magnetic field generated by the d-axis current, and the amount of flux linkage between the low coercivity permanent magnet 3 and the high coercivity permanent magnet 4 is set to zero.

  In the nineteenth embodiment, the amount of magnetic flux generated by the coercive permanent magnet 3 and the amount of magnetic flux generated by the high coercive permanent magnet 4 are the same. Therefore, the magnetization direction of the low coercivity permanent magnet 3 is set to a direction in which a linkage magnetic flux is generated in a direction opposite to the linkage magnetic flux of the high coercivity permanent magnet 4, and a magnetizing magnetic field of 250 kA / m or more is applied to the low coercivity permanent magnet 3. Can be fully magnetized. That is, it is ensured that the total interlinkage magnetic flux of the permanent magnet is set to 0 without being affected by atmospheric conditions such as fluctuations in the magnetization current and temperature at the time of magnetization simply by applying a magnetizing magnetic field of 250 kA / m or more. Easy to do.

  The magnetization direction of the permanent magnet in the second and subsequent embodiments is the same as that of the first embodiment shown in FIG.

Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of the 1st Embodiment of this invention. The figure which shows the magnetic characteristic of the low coercive force permanent magnet and the high coercive force permanent magnet which were used for the 1st Embodiment of this invention. Sectional drawing which shows the magnetic flux of the permanent magnet of the initial state of the rotor in the 1st Embodiment of this invention. Sectional drawing which shows the magnetic flux of the magnetization magnetic field by the d-axis current of the rotor in the 1st Embodiment of this invention. Sectional drawing which shows the magnetic flux after the magnetizing magnetic field by the d-axis current of the rotor in the 1st Embodiment of this invention acts. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of the 4th Embodiment of this invention. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of the 5th Embodiment of this invention. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of the 6th Embodiment of this invention. The figure which showed the change of the torque with respect to the central angle (alpha) of the magnetic pole in the 6th Embodiment of this invention. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of the 8th Embodiment of this invention. Sectional drawing of the longitudinal direction of the low coercive force permanent magnet of the 8th Embodiment of this invention. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of the 9th Embodiment of this invention. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of the 10th Embodiment of this invention. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of the 11th Embodiment of this invention. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of the 12th Embodiment of this invention. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of 13th Embodiment of this invention. Sectional drawing of the rotor of the permanent-magnet-type rotary electric machine of 14th Embodiment of this invention. Sectional drawing of the permanent magnet type rotary electric machine which employ | adopted the rotor of the 1st Embodiment of this invention. Sectional drawing of the rotor of the conventional embedded permanent magnet motor.

Explanation of symbols

1 Rotor 2 Rotor Core 3 Low Coercivity Permanent Magnet 3A High Coercivity Permanent Magnet 3B High Coercivity Permanent Magnet 4 High Coercivity Permanent Magnet 4A Low Coercivity Permanent Magnet 4B High Coercivity Permanent Magnet 5 First Cavity 6 Second Cavity 7 Magnetic core part of iron core 8 Recessed part 9 Magnetic barrier 10 Protrusion 11 Slit 12 Slit

Claims (32)

A stator provided with a stator winding;
A low coercivity permanent magnet having a coercive force such that the magnetic flux density is irreversibly changed by a magnetic field generated by the current of the stator winding in the rotor core, and a coercivity more than twice that of the low coercivity permanent magnet. A permanent magnet type rotating electrical machine comprising a rotor having a high coercive force permanent magnet disposed therein.   One of the low coercive force permanent magnet and the high coercive force permanent magnet is disposed on the outer peripheral side of the rotor core, and the other is disposed on the inner peripheral side of the rotor core. Item 10. The permanent magnet type rotating electrical machine according to Item 1.   3. The permanent magnet according to claim 2, wherein the low coercive force permanent magnet is disposed on an outer peripheral side of the rotor core, and the high coercive force permanent magnet is disposed on an inner peripheral side of the rotor core. Rotary electric machine.   The low coercive force permanent magnet is magnetized in a 45 ° to 135 ° direction or a −45 ° to −135 ° direction with respect to a q axis that is a central axis between magnetic poles of the rotor. Item 4. The permanent magnet type rotating electric machine according to Item 3.   The low coercive force permanent magnet is magnetized in the direction of 45 ° to 135 ° or −45 ° to −135 ° with respect to the q axis that is the central axis between the magnetic poles of the rotor, and the high coercive force permanent magnet is 4. The permanent magnet type rotating electric machine according to claim 3, wherein the permanent magnet type rotating electric machine is magnetized in a direction of −45 ° to 45 ° or −135 ° to −225 ° with respect to a d-axis serving as a magnetic pole central axis of the rotor.   3. The permanent magnet according to claim 2, wherein the high coercive force permanent magnet is disposed on an outer peripheral side of the rotor core, and the low coercive force permanent magnet is disposed on an inner peripheral side of the rotor core. Rotary electric machine.   The high coercive force permanent magnet is magnetized in a 45 ° to 135 ° direction or a −45 ° to −135 ° direction with respect to a q axis that is a central axis between magnetic poles of the rotor. The permanent magnet type rotating electrical machine described in 1.   The high coercive force permanent magnet is magnetized in the direction of 45 ° to 135 ° or −45 ° to −135 ° with respect to the q axis which is the central axis between the magnetic poles of the rotor, and the low coercive force permanent magnet is rotated. The permanent magnet type rotating electrical machine according to claim 6, wherein the permanent magnet type rotating electric machine is magnetized in a -45 ° to 45 ° or -135 ° to -225 ° direction with respect to a d-axis serving as a magnetic pole central axis of the child.   The radial cross-sectional shape of the rotor is a shape in which the low coercive force permanent magnet and the high coercive force permanent magnet surround a rotor core portion that serves as a magnetic pole portion. The permanent magnet type rotating electrical machine described in 1.   The back electromotive force generated by the high coercive force permanent magnet when the rotor reaches the maximum rotation speed is set to be equal to or lower than a withstand voltage of an inverter electronic component that is a power source of the permanent magnet type rotating electrical machine. The permanent-magnet-type rotary electric machine in any one of -9.   The amount of magnetic flux by the high coercivity permanent magnet in a state where the amount of magnetic flux between the low coercivity permanent magnet and the high coercivity permanent magnet is maximum is smaller than the maximum amount of magnetic flux of the low coercivity permanent magnet. Item 11. The permanent magnet type rotating electrical machine according to any one of Items 1 to 10.   The rotor iron core has a shape in which a magnetic resistance in a d-axis direction serving as a magnetic pole central axis of the rotor is reduced and a magnetic resistance in a q-axis direction serving as a central axis between the magnetic poles is increased. Item 12. The permanent magnet type rotating electrical machine according to any one of Items 1 to 11.   The permanent magnet type rotating electrical machine according to any one of claims 3 to 5, and 9 to 12, wherein a magnetic resistance of a portion of the rotor near the air gap side of the low coercive force permanent magnet is increased.   The low coercivity permanent magnet is arranged in the radial direction of the rotor on the outer peripheral side of the rotor core, and the outer end of the low coercivity permanent magnet is excluded except for the radially outer end of the low coercivity permanent magnet. The permanent magnet type rotating electrical machine according to any one of claims 1 to 3 and 9 to 13, wherein an air gap side iron core portion in the vicinity of the portion is recessed.   The low coercive force permanent magnet is arranged in the radial direction of the rotor on the outer peripheral side of the rotor core, the magnetic pole central portion of the rotor core is the outermost peripheral portion of the rotor core, and from the vicinity of the magnetic pole central portion 14. The air gap side iron core portion in the vicinity of the radially outer end portion of the low coercive force permanent magnet is recessed from the outermost peripheral portion of the rotor iron core. 15. The permanent magnet type rotating electrical machine described in 1.   The high coercive force permanent magnet is arranged in the radial direction of the rotor on the outer peripheral side of the rotor core, except for the radially outer end portion of the high coercive force permanent magnet, in the vicinity of the outer end portion of the high coercive force permanent magnet. The permanent magnet type rotating electric machine according to any one of claims 1, 2, 6, and 9 to 13, wherein the air gap side iron core portion is recessed.   The high coercive force permanent magnet is arranged in the radial direction of the rotor on the outer peripheral side of the rotor core, the magnetic pole central portion of the rotor core is the outermost peripheral portion of the rotor core, and from the vicinity of the magnetic pole central portion 14. The air gap side iron core portion in the vicinity of the radially outer end portion of the high coercive force permanent magnet is recessed from the outermost peripheral portion of the rotor iron core. The permanent magnet type rotating electrical machine described in 1.   2. The magnetic pole central portion of the rotor core is formed by an arc having the maximum radius of the rotor, and the central angle of the circular arc of the magnetic pole central portion is in an electrical angle range of 90 to 140 degrees. The permanent-magnet-type rotary electric machine in any one of -17.   The low coercivity permanent magnet is disposed on the outer peripheral side of the rotor core, and the magnetization direction thickness of the low coercivity permanent magnet is smaller than the magnetization direction thickness of the high coercivity permanent magnet. The permanent magnet type rotating electrical machine according to any one of? 5 and 9-18.   The low coercivity permanent magnet is disposed on the outer peripheral side of the rotor core, and the magnetization direction thickness of the low coercivity permanent magnet is not constant. Permanent magnet type rotating electric machine.   The low coercivity permanent magnet is disposed on the outer peripheral side of the rotor core, and the magnetization direction thickness of the low coercivity permanent magnet varies stepwise. The permanent magnet type rotating electrical machine described in 1.   The low coercive force permanent magnet is arranged on the outer peripheral side of the rotor core, and the low coercive force permanent magnet has a shape in which the thickness on the outer peripheral side of the rotor is thinner than the thickness on the inner peripheral side of the rotor. The permanent magnet type rotating electrical machine according to any one of claims 1 to 5 and 9 to 21.   The magnetic barrier longer in the circumferential direction than the thickness of the said permanent magnet was provided in the air gap side edge part of the permanent magnet arrange | positioned at the outer peripheral side of the said rotor, The Claim 1 characterized by the above-mentioned. Permanent magnet type rotating electric machine.   The low coercive force permanent magnet is disposed on the outer peripheral side of the rotor core, and a magnetic barrier that is longer in the circumferential direction than the thickness of the low coercive force permanent magnet is provided at the air gap side end of the low coercive force permanent magnet. The permanent magnet type rotating electrical machine according to any one of claims 1 to 5 and 9 to 22.   The slit is provided in the iron core part of the magnetic pole part in the said rotor so that the magnetoresistance of the q-axis direction used as the central axis between the magnetic poles in the said rotor may be enlarged. The permanent magnet type rotating electric machine described.   When the permanent magnet type rotating electrical machine rotates at a high speed near or exceeding the maximum voltage of the power supply, the interlinkage magnetic flux generated by the low coercive force permanent magnet and the high coercive force permanent magnet is reduced. The permanent magnet type rotating electrical machine according to any one of claims 1 to 25, wherein the low coercive force permanent magnet is magnetized by a magnetic field generated by an electric current to adjust a total amount of flux linkage.   At the time of low-speed rotation where the voltage of the permanent magnet type rotating electrical machine is equal to or lower than the maximum voltage of the power supply, the current of the stator winding is increased so that the linkage flux between the low coercivity permanent magnet and the high coercivity permanent magnet increases. The low coercive force permanent magnet is magnetized by a magnetic field formed by the magnetic field, and the low coercive force permanent magnet and the high coercive force permanent magnet at the time of high-speed rotation near or exceeding the maximum voltage of the power supply. 26. The amount of interlinkage magnetic flux is adjusted by magnetizing the low coercive force permanent magnet with a magnetic field formed by a current of the stator winding so as to reduce interlinkage magnetic flux by the magnetic flux. The permanent magnet type rotating electrical machine according to any one of the above.   The amount of magnetic flux of the low coercivity permanent magnet is adjusted by a magnetic field generated by the current of the stator winding, and the amount of flux linkage between the low coercivity permanent magnet and the high coercivity permanent magnet is set to zero. The permanent magnet type rotating electrical machine according to any one of claims 1 to 27.   The permanent magnet type rotating electric machine according to any one of claims 1 to 28, wherein the amount of magnetic flux generated by the low coercive force permanent magnet and the amount of magnetic flux generated by the high coercive force permanent magnet are the same.   30. The permanent magnet type rotating electrical machine according to claim 1, wherein the magnetization direction of the low coercive force permanent magnet is reversed in both directions by a magnetic field generated by a current of the stator winding.   The permanent magnet type according to any one of claims 1 to 30, wherein the low coercivity permanent magnet and the high coercivity permanent magnet are provided with slits in the rotor core so that a demagnetizing field acting on each other is reduced. Rotating electric machine.   The permanent magnet type rotating electrical machine according to any one of claims 1 to 31, wherein each of the permanent magnets is a high coercive force permanent magnet.

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