JP2010041842A - Permanent-magnet type rotary electric machine and permanent-magnet type motor drive system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permanent-magnet type rotary electric machine that performs variable-speed operation in a wide range from low speed to high speed, achieves operation at a higher speed compared with a conventional one while achieving high torque in a low-speed rotation zone, high output in a middle/high-speed rotation zone, improvement in efficiency, reliability, and manufacturability, and material reduction, and a permanent-magnet type motor drive system for driving the same. <P>SOLUTION: The permanent-magnet type rotary electric machine includes a stator having an armature winding, and a rotor 1a. The rotor 1a is configured such that a plurality of permanent magnets 4a are provided in each of a plurality of rotor cores 2a, configured by being laminated and arranged oppositely to each other on the inner peripheral side of the stator via each air gap, along the circumferential direction. The rotor 1a is formed by being axially divided for each prescribed block. The rotor 1a is arranged with a plurality of permanent magnets in each prescribed block in order to form a magnetic pole. The plurality of permanent magnets are one type selected from among the plural types of permanent magnets respectively having at least one of a different shape and a different magnetic property. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a permanent magnet type rotating electrical machine and a permanent magnet motor drive system using the permanent magnet type rotating electrical machine.

  Currently, the permanent magnet type rotating electrical machines whose application range has been expanded are roughly divided into two types. A surface magnet type permanent magnet type rotating electrical machine in which a permanent magnet is attached to the outer periphery of a rotor core, and an embedded type permanent magnet type rotating electrical machine in which a permanent magnet is embedded in a rotor core (for example, see Patent Document 1). . In recent years, the latter embedded permanent magnet type rotating electrical machines have been increasingly applied as variable speed drive motors.

  A conventional embedded permanent magnet type rotating electrical machine has a configuration in which a rotor is provided inside, and a stator is arranged on the outer periphery thereof via an air gap. This stator is configured by accommodating the armature winding in a slot formed inside the stator core. FIG. 10 is a radial cross-sectional view showing a configuration of a rotor 1 of a conventional embedded permanent magnet type rotating electrical machine. The rotor 1 is accommodated in a stator (not shown), and has a configuration in which rectangular cavities are provided in the outer peripheral portion of the rotor core 2 by an equal number and the number of poles. A rotor 1 shown in FIG. 10 is an eight-pole rotor, and eight cavities are provided in the rotor core 2 and a permanent magnet 4 is inserted into each of them. The permanent magnet 4 is magnetized in a direction perpendicular to the radial direction of the rotor 1 or the side (long side in FIG. 10) facing the air gap surface in the rectangle of the cross section of the permanent magnet 4. The permanent magnet 4 is mainly an NdFeB permanent magnet having a high coercive force so as not to be demagnetized by a load current. The rotor core 2 is formed by laminating electromagnetic steel plates punched out of cavities.

  Further, as a rotating electric machine having excellent variable speed characteristics and high output, a permanent magnet type reluctance rotating electric machine described in Patent Document 2 and Patent Document 3 is known. Further, Patent Document 4 describes a permanent magnet type rotating electrical machine that makes the magnetic flux of the magnet variable. This rotating electrical machine is capable of variable speed operation in a wide range from low speed to high speed, and is intended to increase the torque in the low speed rotation range, increase the output in the middle / high speed rotation range, and improve the efficiency.

  In general, in a permanent magnet type rotating electrical machine, a constant interlinkage magnetic flux is always generated by the permanent magnet due to its structural characteristics, and therefore the induced voltage by the permanent magnet increases in proportion to the rotational speed. Therefore, when variable speed operation is performed from low speed to high speed, the induced voltage (back electromotive voltage) by the permanent magnet becomes extremely high at high speed rotation. The induced voltage by the permanent magnet is applied to the electronic component of the inverter. When the applied voltage exceeds the withstand voltage of the electronic component, the component breaks down. 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, but when such a design is adopted, the output in the low speed region of the permanent magnet type rotating electrical machine and Efficiency is reduced.

  On the other hand, 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 is It stops flowing. As a result, the output is greatly reduced in the high-speed rotation range, and furthermore, a wide range of variable speed operation up to the high-speed rotation cannot be performed. Therefore, recently, as a method for expanding the variable speed range, the magnetic flux weakening control as described in Non-Patent Document 1 has begun to be applied. In the case of a permanent magnet type rotating electrical machine, the total interlinkage magnetic flux amount is composed of a magnetic flux caused by a d-axis current and a magnetic flux caused by a permanent magnet. The weakening magnetic flux control pays attention to this, and performs control to reduce the total amount of interlinkage magnetic flux of the armature winding by generating magnetic flux due to negative d-axis current. In the flux weakening control, the high coercive force permanent magnet 4 is configured such that the operating point of the magnetic characteristics (BH characteristics) changes within a reversible range. For this reason, an NdFeB magnet having a high coercive force characteristic is applied to the permanent magnet so as not to be irreversibly demagnetized by the demagnetizing field of the flux weakening control.

  In operation using the flux-weakening control, the linkage flux decreases due to the magnetic flux due to the negative d-axis current, and therefore the decrease in linkage flux creates a voltage margin with respect to the voltage upper limit value. And since the electric current which becomes a torque component can be increased, the output in a 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, in the permanent magnet type rotating electrical machine to which the flux weakening control is applied, since the negative d-axis current that does not contribute to the output is continuously supplied, the copper loss increases and the efficiency deteriorates. Furthermore, a demagnetizing field due to a negative d-axis current generates a harmonic magnetic flux, and an increase in voltage caused by the harmonic magnetic flux or the like is weakened, creating a limit of voltage reduction by magnetic flux control. Therefore, even if the flux-weakening control is applied to the embedded permanent magnet type rotating electrical machine, it is difficult to operate at a variable speed of more than 3 times the base speed. Furthermore, the above-described harmonic magnetic flux increases the iron loss, and the efficiency is greatly reduced in the middle and high speed ranges. In addition, vibration may be generated by electromagnetic force due to harmonic magnetic flux.

  When an embedded permanent magnet motor is applied to a drive motor for a hybrid vehicle, the motor is rotated when driven by an engine alone. At medium and high speeds, the induced voltage from the permanent magnet of the motor increases. Therefore, in order to suppress the rise of the induced voltage within the power supply voltage, the negative d-axis current is continuously supplied by the magnetic flux weakening control. However, in this state, since the motor generates only a loss, there is a problem that the overall operation efficiency deteriorates.

As a solution to these problems, Patent Document 5 discloses that variable speed operation is possible in a wide range from low speed to high speed, high torque in the low speed rotation range, high output in the middle / high speed rotation range, and efficiency. A rotor of a permanent magnet type rotating electrical machine that can improve the reliability, improve the reliability, improve the productivity, reduce the material, and reduce the rare material is described. A permanent magnet type rotating electrical machine to which this rotor is applied uses a permanent magnet having a small product of coercive force and magnetization direction thickness, and a permanent magnet having a large product of coercive force and magnetization direction thickness. The amount of flux linkage with the stator is increased or decreased by irreversibly magnetizing a permanent magnet having a small product of magnetization direction thickness according to operating conditions.
JP 7-336919 A JP-A-11-27913 JP-A-11-136912 JP 2006-280195 A JP 2008-48514 A "Design and control of embedded magnet synchronous motor", Yoji Takeda et al., Ohm Publishing

  However, the rotating electrical machine described in Patent Document 5 described above has a problem that the occupied portion of the permanent magnet in which the product of the coercive force and the thickness in the magnetization direction is small increases, and the structure becomes complicated, so that high-speed rotation is difficult. is there. In addition, since the rotating electrical machine has a permanent magnet whose product of coercive force and magnetization direction thickness is small and the magnet longitudinal direction is installed in a direction parallel to a straight line passing through the rotor central axis, it is difficult to increase the rotor inner diameter. There is room for improvement in terms of manufacturability, reliability, and material reduction.

  The present invention has been made to solve the above-described problems of the prior art, and can be operated at a variable speed in a wide range from low speed to high speed, enabling operation at a higher speed than conventional, Permanent magnet type rotating electrical machine that can achieve high torque in the low speed rotation range, high output in the middle / high speed rotation range, improved efficiency, improved reliability, improved manufacturability, and material reduction, and a permanent magnet electric motor that drives it It is an object to provide a drive system.

  In order to solve the above-mentioned problem, a permanent magnet type rotating electrical machine according to the present invention is configured by arranging and laminating a stator having an armature winding and an inner circumferential side of the stator via an air gap. In the permanent magnet type rotating electrical machine, comprising a plurality of permanent magnets along the circumferential direction in each of the plurality of rotor cores, and a rotor configured to be divided into predetermined blocks in the axial direction. In the rotor, one type of the plurality of permanent magnets selected from a plurality of types of permanent magnets having at least one of different shapes and magnetic characteristics is arranged for each predetermined block to form a magnetic pole. Features.

  Moreover, in order to solve the said subject, the permanent-magnet-motor drive system which concerns on this invention drives the permanent-magnet-type rotary electric machine of any one of Claim 1 thru | or 11, and the said permanent-magnet-type rotary electric machine. And a magnetizing unit for passing a magnetizing current for controlling the magnetic flux of the permanent magnet.

  According to the present invention, variable speed operation is possible in a wide range from low speed to high speed, and it is possible to operate at a higher speed than before, increasing the torque in the low speed rotation range and in the middle / high speed rotation range. High output, efficiency improvement, reliability improvement, manufacturability improvement, and material reduction can be realized.

  Embodiments of a permanent magnet type rotating electrical machine and a permanent magnet motor drive system according to the present invention will be described below in detail with reference to the drawings.

First, the configuration of the first embodiment will be described with reference to FIGS. 1 to 3. 1 is an external view of a rotor 1a of a permanent magnet type rotating electric machine according to a first embodiment of the present invention. FIG. 2 is a radial cross-sectional view of the block 20 (or 23) of the rotor 1a of the permanent magnet type rotating electric machine according to the first embodiment of the present invention. FIG. 3 is a radial cross-sectional view of the block 21 (or 22) of the rotor 1a of the permanent magnet type rotating electric machine according to the first embodiment of the present invention. 10 that are the same as or equivalent to those in the prior art of FIG. 10 are denoted by the same reference numerals as those described above, and redundant descriptions are omitted. Further, in each of the following embodiments, an 8-pole permanent magnet type rotating electrical machine is illustrated, but the permanent magnet type rotating electrical machine of this embodiment that can be similarly applied to other numbers of poles has an armature winding. And a rotor 1a that is arranged to be opposed to each other through an air gap on the inner peripheral side of the stator and divided into predetermined blocks in the axial direction. As shown in FIG. 1, the rotor 1a of the present embodiment is configured by being divided into four blocks 20, 21, 22, and 23 in the axial direction. Moreover, the rotor 1a is provided with a plurality of permanent magnets 4a along the circumferential direction in each of a plurality of rotor cores 2a formed by stacking. The rotor core 2a is configured by stacking silicon steel plates, for example.

  Furthermore, the rotor 1a forms a magnetic pole by arranging a plurality of types of permanent magnets selected from a plurality of types of permanent magnets having different shapes and magnetic characteristics for each predetermined block. Specifically, in the rotor 1a, in the blocks 20 and 23, as shown in FIG. 2, eight permanent magnets 4a are provided in a radial cross section in the rotor core 2a. Further, a magnetic barrier 7 is provided between the permanent magnets 4a by a gap or the like.

  On the other hand, the rotor 1a is provided with eight permanent magnets 3 in the radial cross section in the rotor core 2a in the blocks 21 and 22, as shown in FIG. These permanent magnets 3 are provided at positions corresponding to the magnetic barriers 7 in the adjacent blocks 20 (or 23). Further, a magnetic barrier 8 such as a gap is provided between the permanent magnets 3 and corresponds to the position of the permanent magnet 4a in the adjacent block 20 (or 23).

  Each of the plural types of permanent magnets is different from other types of permanent magnets in the product of coercive force and magnetization direction thickness. In the present embodiment, the permanent magnet 4a is a magnet having a large product of coercive force and magnetization direction thickness, for example, an NdFeB magnet. The permanent magnet 3 is a magnet having a small product of the coercive force and the magnetization direction thickness, such as an alnico magnet or an FeCrCo magnet. Further, as the permanent magnet 3, a composite magnet of an alnico magnet and a ferrite magnet, or a composite magnet of an FeCrCo magnet and a ferrite magnet can be applied.

  Further, each of the plurality of types of permanent magnets has a magnetization direction different from that of other types of permanent magnets. In the present embodiment, the magnetization directions of the permanent magnet 4a and the permanent magnet 3 are different from each other. The permanent magnet 4a is disposed substantially in the circumferential direction of the rotor 1a, and the magnetization direction of the permanent magnet 4a is substantially the radial direction of the rotor 1a. On the other hand, the permanent magnet 3 is disposed substantially along the radial direction of the rotor 1a, and the magnetization direction of the permanent magnet 3 is substantially the circumferential direction of the rotor 1a. Each of the eight sets of the permanent magnet 3 and the permanent magnet 4a is installed in a convex shape on the inner diameter side of the rotor 1a, and the magnetization directions of the permanent magnets 3 and 4a are both substantially smaller in magnet size.

  FIG. 4 shows the magnetic characteristics of an Alnico magnet (AlNiCo) for the permanent magnet 3, an FeCrCo magnet, and an NdFeB magnet for the permanent magnet 4a, which are applied to the permanent magnet type rotating electrical machine of the present 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 950 kA / m of the NdFeB magnet. Further, the coercive force of the FeCrCo magnet is about 60 kA / m, which is 1/15 of 950 kA / m of the NdFeB magnet. It can be seen that the alnico magnet and the FeCrCo magnet have a considerably lower coercive force than the NdFeB magnet.

  In the present embodiment, an alnico magnet having a coercive force of 120 kA / m is applied to the permanent magnet 3 in which the product of the coercive force and the magnetization direction thickness is small. Further, an NdFeB magnet having a coercive force of 1000 kA / m is applied to the permanent magnet 4a having a large product of the coercive force and the magnetization direction thickness.

  As shown in FIG. 2, the permanent magnet 4a is embedded in the rotor core 2a, and cavities 5 are provided at both ends of the permanent magnet 4a. As shown in FIG. 3, the permanent magnet 3 is embedded in the rotor core 2 a, and cavities 6 are provided at both ends of the permanent magnet 3.

  The permanent magnet 3 is arranged along the radial direction of the rotor 1a that coincides with the q axis that is the central axis between the magnetic poles. In addition, the easy magnetization direction of the permanent magnet 3 made of an alnico magnet is substantially the circumferential direction of the rotor 1a and is perpendicular to the radius of the rotor 1a. That is, in the rotor core 2a having the permanent magnet 3 that exhibits magnetic flux change or polarity reversal due to magnetization among the plurality of rotor cores 2a, the easy magnetization direction of the permanent magnet 3 is the radial direction of its own rotor core 2a. The magnetic poles are formed by arranging the permanent magnets 3 so as to intersect with each other at right angles.

  A permanent magnet 4a made of a high coercive force NdFeB magnet is embedded in the rotor core 2a, and cavities 5 are provided at both ends thereof. One permanent magnet 4a is arranged in a substantially circumferential direction of the rotor 1a so as to be sandwiched between two magnetic barriers 7 on the inner peripheral side of the rotor 1a. The direction of easy magnetization of the permanent magnet 4a is substantially perpendicular to the circumferential direction of the rotor 1a (in FIG. 2, perpendicular to the long side of the rectangular cross section of the permanent magnet 4a).

  In addition, the hollow parts 5 and 6 are provided as needed for the magnetic flux short circuit of the permanent magnets 4a and 3 and stress relaxation.

  The permanent magnet 3 is disposed in the q-axis direction that is the central axis between the magnetic poles, and the magnetization direction is 90 ° or −90 ° with respect to the q-axis. In the adjacent permanent magnets 3, the magnetic pole surfaces facing each other are made to have the same polarity. The permanent magnet 4a is arranged in a direction perpendicular to the d-axis, and the magnetization direction is 0 ° or 180 ° with respect to the d-axis. In the adjacent permanent magnets 4a, the magnetic poles have opposite polarities.

  The configuration of the permanent magnet motor drive system of the present invention will be described. This permanent magnet motor drive system includes the above-described permanent magnet type rotating electric machine, an inverter for driving the permanent magnet type rotating electric machine, and a magnetizing unit for passing a magnetizing current for controlling the magnetic flux of the permanent magnet. In this embodiment, the magnetizing portion is an armature winding with respect to the permanent magnet 3 having a product of coercive force and magnetization direction thickness which is smaller than that of other types of permanent magnets among a plurality of types of permanent magnets. The amount of magnetic flux of the permanent magnet 3 is irreversibly changed by a magnetic field generated by passing an electric current, or the polarity of the permanent magnet 3 is reversed.

  The inverter 4 converts, for example, DC power obtained from a DC power source into AC power and supplies the AC power to the permanent magnet type rotating electrical machine. Although the magnetizing part can be provided independently, the inverter 4 may be used as the magnetizing part. In that case, the inverter 4 supplies a magnetizing current for controlling the magnetic flux of the low-coercivity variable magnet (permanent magnet 3) of the permanent magnet type rotating electrical machine corresponding to the magnetizing unit.

  Next, the operation of the present embodiment configured as described above will be described. In the present embodiment, a magnetic field is formed by applying a pulse-like current whose energization time is extremely short (about 0.1 ms to 10 ms) to the armature winding of the stator, and the magnetic field is applied to the permanent magnet 3. . The pulse current that forms the magnetic field for magnetizing the permanent magnet is the d-axis current component of the armature winding of the stator. If the magnetizing magnetic field is 250 kA / m, ideally, a sufficient magnetizing magnetic field acts on the permanent magnet 3, and the permanent magnet 4a does not have irreversible demagnetization due to magnetization.

  FIG. 5 is a diagram showing the direction of the magnetic flux of the permanent magnet when the permanent magnet is irreversibly magnetized so that the flux linkage with the stator is maximized, and only the two poles developed on the Z-θ plane are shown. Indicates. FIG. 6 is a perspective view of the rotor 1a shown together with the direction of the magnetic flux of the permanent magnets of the blocks 20 and 21 when the interlinkage magnetic flux with the stator is maximized. The magnetizing unit in the permanent magnet motor system of the present invention magnetizes at least one permanent magnet among the permanent magnets of the rotor 1a at each magnetic pole by a magnetic field generated by passing a current through the armature winding. The amount of magnetic flux is irreversibly changed.

  By applying a magnetizing magnetic field to magnetize the permanent magnet 3 to the same polarity as the permanent magnet 4a, the magnetic fluxes of the permanent magnet 3 and the permanent magnet 4a are added together at the magnetic pole and the air gap surface. In other words, the permanent magnet 4a generates a magnetic pole and magnetic flux of the original polarity on the central axis in the circumferential direction, and the permanent magnet 3 is in the same direction as the permanent magnet 4a at a position intermediate between the permanent magnets 3 adjacent in the circumferential direction. To generate magnetic poles and magnetic flux. For example, in the block 20 of FIG. 5, the magnetic flux flow 11 indicates the direction of the magnetic flux from the rotor 1a to the stator, but the direction of the magnetic flux in the blocks 21, 22, and 23 at the same θ position is also the same. Therefore, in FIGS. 5 and 6, the interlinkage magnetic flux by the permanent magnets 3 and 4a is increased to be in a magnetized state. The direction connecting the θ position indicating the magnetic flux flows 10 and 11 and the rotation center of the rotor 1a is the main magnetic pole of the rotor 1a and the d-axis. Further, the central axis direction passing through the auxiliary magnetic pole between the adjacent magnetic poles having the opposite polarity is the q axis (the axis connecting the permanent magnet 3 and the rotation center).

  The magnetizing magnetic field is formed by passing a pulse-like current for a very short time through the armature winding of the stator. The current that is energized at this time is a d-axis current component. The pulse current immediately becomes 0 and the magnetizing magnetic field disappears, but the permanent magnet 3 changes irreversibly and generates a magnetic flux in the magnetizing direction.

  Next, an effect | action at the time of reducing the flux linkage with respect to a stator is demonstrated. When a negative d-axis current is passed through the armature winding of the stator to form a magnetic field, the formed magnetic field is almost opposite to the magnetization direction from the center of the magnetic pole of the rotor 1a to the permanent magnet 3 and the permanent magnet 4a. Acts on direction. Since the alnico magnet of the permanent magnet 3 has a small product of coercive force and thickness in the magnetization direction, the magnetic flux is irreversibly reduced by this reverse magnetic field. On the other hand, the NdFeB magnet of the permanent magnet 4a has a large product of the coercive force and the thickness in the magnetization direction, so that the magnetic characteristics are in a reversible range even when receiving the reverse magnetic field Bd, and the magnetization after the magnetization magnetic field due to the negative d-axis current disappears. The state does not change and the amount of magnetic flux does not change. Therefore, only the permanent magnet 3 is demagnetized, and the amount of flux linkage can be reduced.

  Therefore, in the present embodiment, the total amount of interlinkage magnetic flux including the permanent magnets 3 and 4a can be adjusted over a wide range by magnetizing the permanent magnet 3 with the d-axis current. Specifically, in the rotor 1a, a plurality of types of permanent magnets are arranged so that the magnetic fluxes of the permanent magnets forming the magnetic poles are added together. On the other hand, the magnetizing portion of the permanent magnet motor drive system of the present invention irreversibly reduces the interlinkage magnetic flux by the permanent magnet by magnetizing a part of the permanent magnet by the magnetic field generated by flowing current through the armature winding. After the decrease, a magnetic field due to an electric current is generated in the opposite direction to magnetize a part of the permanent magnet to irreversibly increase the amount of flux linkage.

  In the present embodiment, a larger current is applied and the polarity of the permanent magnet 3 is reversed by a strong reverse magnetic field. By inverting the polarity of the permanent magnet 3, the interlinkage magnetic flux can be greatly reduced, and in particular, the interlinkage magnetic flux can be reduced to zero. That is, the magnetizing unit in the permanent magnet motor drive system of the present invention magnetizes at least one permanent magnet among the permanent magnets of the rotor 1a in each magnetic pole by a magnetic field generated by flowing current through the armature winding. The polarity of the permanent magnet can be reversed. Further, the magnetizing portion magnetizes at least one permanent magnet among the permanent magnets of the rotor 1a in each magnetic pole by a magnetic field generated by passing an electric current through the armature winding, so that all the rotor 1a has The amount of flux linkage of the armature winding by the permanent magnet can be made almost zero.

  FIG. 7 is a diagram showing the direction of the magnetic flux of the permanent magnet after the demagnetizing magnetic field due to the negative d-axis current is applied so that the flux linkage with the stator is minimized, and is developed on the Z-θ plane. Only two poles are shown. FIG. 8 is a perspective view of the rotor 1a shown along with the direction of the magnetic flux of the permanent magnets of the blocks 20 and 21 when the interlinkage magnetic flux with the stator is minimized. By applying a demagnetizing magnetic field to magnetize the permanent magnet 3 in the opposite polarity to the permanent magnet 4a, the magnetic flux generated by the permanent magnet 4a flows to the iron core block where the permanent magnet 3 is installed, and the permanent magnet of the opposite polarity. Enter 3. In this embodiment, the magnetic flux generated by the permanent magnet 4 a in the block 20 enters the permanent magnet 3 of the block 21 by the magnetic flux flow 14. Therefore, since it is magnetically short-circuited, the rotor 1a has almost no linkage magnetic flux with respect to the external stator, and is in the same state as when the rotor 1a as a whole is not magnetized.

  In this case, the demagnetizing magnetic field is formed by flowing an extremely short pulse current through the armature winding of the stator. The current that is energized at this time is a negative d-axis current component. The pulse current immediately becomes 0 and the demagnetizing magnetic field disappears. However, the polarity of the permanent magnet 3 is reversed, and a magnetic flux is generated in the direction shown in FIGS.

  Therefore, in the present embodiment, by reversing the polarity of the permanent magnet 3, the total interlinkage magnetic flux amount of the permanent magnets 3 and 4a can be adjusted over a wide range. Specifically, in the rotor 1a, a plurality of types of permanent magnets are arranged so that the magnetic fluxes of the permanent magnets forming the magnetic poles are added together. On the other hand, the magnetizing portion of the permanent magnet motor drive system of the present invention magnetizes a part of the permanent magnet by a magnetic field generated by passing an electric current through the armature winding, and reverses the polarity of the permanent magnet. The magnetic field can be generated in the opposite direction to the previous one, and the polarity of the permanent magnet 3 can be reversed to the original polarity.

  In the conventional rotating electric machine, when the magnetic flux generated by the negative d-axis current of the armature winding is generated to cancel the magnetic flux of the permanent magnet of the rotor 1a, the combined fundamental wave magnetic flux can be reduced to about 50%. However, the harmonic magnetic flux increases considerably, causing harmonic voltage and harmonic iron loss. In addition, it is extremely difficult to set the interlinkage magnetic flux to 0. Even if the fundamental wave can be reduced to 0, the harmonic magnetic flux becomes a considerably large value.

  On the other hand, in the permanent magnet type rotating electrical machine of the present embodiment, the rotor 1a can be uniformly reduced by the magnetic flux of only the permanent magnets 3 and 4a, so that the harmonic magnetic flux is small and the loss is not increased. In the permanent magnet type rotating electric machine according to the present embodiment, the permanent magnet 3 having a small product of the coercive force and the magnetization direction thickness is easily magnetized by the magnetic field generated by the d-axis current. If the magnetic field is sufficient to magnetize the permanent magnet 3, the permanent magnet 4a is in a reversible demagnetized state, and the permanent magnet 4a can maintain the magnetic flux in the state before magnetization even after magnetization.

  The mutual magnetic influence between the permanent magnet 3 of the Alnico magnet and the permanent magnet 4a of the NdFeB magnet will be described. In the demagnetized state, the magnetic field of the permanent magnet 4a acts as a bias magnetic field on the permanent magnet 3, and the magnetic field due to the negative d-axis current and the magnetic field due to the permanent magnet 4a act on the permanent magnet 3 and are easily magnetized. That is, in the rotor 1a, each permanent magnet is arranged so that a bias-like magnetic field acts from the other permanent magnet 4a on the permanent magnet 3 that exhibits a change in magnetic flux or a reversal of polarity in each magnetic pole.

  Further, by increasing the product of the coercive force and the magnetization direction thickness of the permanent magnet 3 to be equal to or greater than the product of the magnetic field strength and the magnetization direction thickness at the operating point when the permanent magnet 4a is unloaded, the flux linkage can be increased. In the magnetic state, the magnetic field of the permanent magnet 4a is overcome and a magnetic flux amount is generated. Therefore, in the permanent magnet type rotating electrical machine of the present invention, the product of the coercive force and the magnetization direction thickness of the permanent magnet 3 having a small product of the coercive force and the magnetization direction thickness in each magnetic pole is the product of the coercive force and the magnetization direction thickness. The large permanent magnet 4a is substantially equal to or more than the product of the magnetic field strength and the magnetization direction thickness at the operating point when no load is applied.

  As described above, according to the permanent magnet type rotating electrical machine and the permanent magnet motor system according to the first embodiment of the present invention, variable speed operation can be performed in a wide range from low speed to high speed, which is higher than conventional. It is possible to drive in. The point of the present invention that is different from Patent Document 5 described as the prior art is that a plurality of types of permanent magnets having different magnetic flux variations due to magnetization are arranged separately in blocks divided in the axial direction, and only in the radial direction. In other words, the amount of flux linkage with respect to the stator can be controlled by causing magnetic fluxes to act in the axial direction.

In order to control the magnetic flow as in a conventional permanent magnet type rotating electrical machine, various design restrictions are required when a plurality of types of permanent magnets are configured in one radial cross section. However, by providing a plurality of types of permanent magnets separately in the block divided in the axial direction as in the present invention, it is not necessary to accommodate a plurality of types of permanent magnets in the same radial cross section, and therefore the degree of freedom in design. It is easy to devise to relax the restrictions on the material strength, enabling higher speed rotation, higher torque in the low speed rotation range, higher output in the middle / high speed rotation range, improved efficiency, and reliability. Improvement of productivity, improvement of manufacturability, and reduction of materials can be realized.

  Moreover, the rotor 1a arrange | positions the permanent magnet 4a with a small change of the magnetic flux by magnetization in the blocks 20 and 23 located in an axial direction both ends among the divided | segmented blocks. This is to prevent the permanent magnet from demagnetizing when torque is applied because the magnetic field at the end of the rotor 1a becomes strong. This is because it becomes easy to control the above.

  Further, in the permanent magnet type rotating electrical machine of the present embodiment, the amount of flux linkage of the permanent magnet 3 can be greatly changed from the maximum to 0 by the d-axis current, and the magnetization direction can be changed in both forward and reverse directions. That is, if the interlinkage magnetic flux of the permanent magnet 4a is the forward direction, the interlinkage magnetic flux of the 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. For this reason, according to the permanent magnet type rotating electrical machine of the present embodiment, the amount of total interlinkage magnetic flux combining the permanent magnet 3 and the permanent magnet 4a is adjusted over a wide range by magnetizing the permanent magnet 3 with the d-axis current. be able to.

  (1) In the low speed region, the permanent magnet 3 is magnetized with a d-axis current so as to have a maximum value in the same direction as the interlinkage magnetic flux of the permanent magnet 4a (magnetization state shown in FIGS. 5 and 6). Since the torque by the permanent magnets 3 and 4a is maximized, the torque and output of the rotating electrical machine can be maximized. That is, the magnetized portion of the permanent magnet motor drive system of the present invention has a product of coercive force and magnetization direction thickness smaller than the others so that the magnetic flux of the permanent magnet of the magnetic pole is added at the maximum torque of the permanent magnet type rotating electrical machine. The permanent magnet 3 is magnetized.

  (2) In the middle / high speed range, the magnetic flux of the permanent magnet 3 is reduced (demagnetized state in FIGS. 7 and 8), and the total flux linkage is reduced. As a result, the voltage of the rotating electrical machine is lowered, so that there is a margin with respect to the upper limit value of the power supply voltage, and the rotational speed (frequency) can be further increased. That is, the magnetized portion of the permanent magnet motor drive system according to the present invention has a smaller product of the coercive force and the thickness in the magnetization direction than the other at the time of a light load with a small torque and at a medium speed rotation range and a high speed rotation range. Thus, the magnetic field is magnetized by a magnetic field to reduce the magnetic flux, or the polarity of the permanent magnet 3 is reversed by the magnetic field.

  In this manner, the permanent magnet type rotating electrical machine of the present embodiment can realize a wide range of variable speed operation from high speed to low speed rotation to ultra high speed rotation. In addition, in the permanent magnet type rotating electrical machine of the present embodiment, since the magnetizing current when changing the flux linkage flows only for an extremely short time, the loss can be remarkably reduced, so that the efficiency becomes high in a wide operating range.

  Next, the influence of torque current in the permanent magnet type rotating electrical machine of the present embodiment will be described. When the rotating electrical machine generates an output, a q-axis current is passed through the armature winding of the stator to generate a torque by the magnetic action of the q-axis current and the magnetic flux of the permanent magnets 3 and 4a. At this time, a magnetic field is generated by the q-axis current. However, since the permanent magnet 3 is arranged in the q-axis direction and the magnetization direction is a direction perpendicular to the q-axis direction, the magnetization direction of the permanent magnet 3 and the magnetic field due to the q-axis current are orthogonal to each other. The effect of the magnetic field due to the current is minimal.

  The magnetizing part of the permanent magnet motor drive system of the present invention magnetizes the permanent magnet 3 with a magnetic field generated by d-axis current to irreversibly change the amount of magnetic flux of the permanent magnet 3, or reverses the polarity of the permanent magnet 3 with a magnetic field. Further, the torque can be controlled by the q-axis current.

  Next, the operation of the cavities 5 and 6 provided at both ends of the permanent magnets 3 and 4a in the permanent magnet type rotating electrical machine of the present embodiment will be described. The cavities 5 and 6 alleviate stress concentration and demagnetizing field on the rotor core 2a when centrifugal force by the permanent magnets 3 and 4a acts on the rotor core 2a.

  As shown in FIGS. 2 and 3, by providing the cavities 5 and 6, the rotor core 2a can have a curved shape, and the stress is relieved. Moreover, the magnetic field by an electric current concentrates on the corner | angular part of the permanent magnets 3 and 4a, a demagnetizing field acts, and a corner | angular part may be irreversibly demagnetized. In the present embodiment, since the cavities 6 and 5 are provided at the ends of the permanent magnets 3 and 4a, the demagnetizing field due to the current at the ends of the permanent magnets 3 and 4a is alleviated.

  Next, the structural strength of the rotor 1a in the permanent magnet type rotating electrical machine of the present embodiment will be described. The permanent magnet 3 and the permanent magnet 4a are embedded in the rotor core 2a, and the permanent magnets 3 and 4a are fixed by the rotor core 2a.

  With the above configuration, the permanent magnet type rotating electrical machine of the present embodiment has the following effects. Assuming that the linkage flux of the permanent magnet 4a of the NdFeB magnet is the positive direction, the linkage flux of the permanent magnet 3 of the alnico magnet 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. . Therefore, in the present embodiment, the total amount of interlinkage magnetic flux including the permanent magnets 3 and 4a can be adjusted over a wide range by magnetizing the permanent magnet 3 with the d-axis current. Further, since the total flux linkage of the permanent magnets 3 and 4a can be adjusted over a wide range, the voltage of the permanent magnet type rotating electrical machine can be adjusted over a wide range. In addition, since magnetization is performed with a pulse-like current for a very short time, it is not necessary to constantly weaken the magnetic flux current and loss can be greatly reduced. Further, since it is not necessary to perform the flux-weakening control as in the prior art, harmonic iron loss due to harmonic magnetic flux does not occur. As described above, the permanent magnet type rotating electrical machine according to the present embodiment enables variable speed operation in a wide range from high speed to low speed to high speed, and also enables high efficiency in a wide operating range. In addition, as for the induced voltage by the permanent magnet, the permanent magnet 3 can be magnetized by the d-axis current to reduce the total amount of magnetic flux linkage of the permanent magnets 3 and 4a. The parts are not damaged and the reliability is improved. Further, in a state where the permanent magnet type rotating electrical machine is rotated with no load, the permanent magnet 3 can be magnetized with a negative d-axis current to reduce the total flux linkage of the permanent magnets 3 and 4a. As a result, the induced voltage is remarkably lowered, and there is almost no need to constantly apply a weak magnetic flux current for lowering the induced voltage, thereby improving the overall efficiency. In particular, when the permanent magnet type rotating electrical machine of the present embodiment is mounted and driven on a commuter train with a long coasting operation time, the overall driving efficiency is greatly improved.

  In the permanent magnet type rotating electrical machine of the present invention, the amount of flux linkage can be changed by irreversibly magnetizing the permanent magnet 3 with a magnetic field generated by a d-axis current. Further, by always generating a magnetic flux due to a negative d-axis current, the linkage flux composed of the magnetic flux due to the negative d-axis current and the magnetic flux due to the permanent magnets 3 and 4a can be adjusted by the magnetic flux due to the negative d-axis current. . That is, the amount of interlinkage magnetic flux can be changed greatly by irreversibly changing the magnetization state of the permanent magnet 3, and the amount of interlinkage magnetic flux can be finely adjusted by a negative d-axis current that is always energized. it can. At this time, since the amount of interlinkage magnetic flux that is finely adjusted by the negative d-axis current that is always energized is small, the negative d-axis current that continues to flow constantly becomes small and no significant loss occurs. As a result, according to the permanent magnet type rotating electrical machine of the present embodiment, the amount of interlinkage magnetic flux that is the basis of the voltage can be varied and finely adjusted, and can be varied with high efficiency.

  The magnetizing portion of the permanent magnet motor drive system of the present invention magnetizes the permanent magnet 3 with a magnetic field generated by the d-axis current during operation of the permanent magnet type rotating electrical machine, and irreversibly changes the amount of magnetic flux of the permanent magnet 3; An operation of reversing the polarity of the permanent magnet 3 with a magnetic field and an operation of reversibly changing the amount of interlinkage magnetic flux of the armature winding generated in the permanent magnet by the magnetic flux generated by the d-axis current are selectively executed. You can also

  The permanent magnet type rotating electrical machine according to the second embodiment of the present invention is the same as the permanent magnet type rotating electrical machine according to the first embodiment. The permanent magnet 4a has a large product of coercive force and magnetization direction thickness among a plurality of types of permanent magnets. Is an NdFeB-based permanent magnet containing almost no Dy element. Therefore, other configurations are the same as those in the first embodiment.

  When the amount of Dy element is small, the residual magnetic flux density of the permanent magnet is increased, and a residual magnetic flux density of 1.33 T or more can be obtained at 20 ° C.

  Conventional rotating electrical machines perform flux-weakening control with a negative d-axis current in order to suppress voltage increase due to induced voltage at high speed. At this time, an excessive reverse magnetic field acts on the permanent magnet, the permanent magnet may be irreversibly demagnetized, and the output may remain significantly reduced. As a countermeasure, a magnet having a large coercive force is applied among NdFeB magnets. As a method for increasing the coercive force of the NdFeB magnet, Dy element is added, but this reduces the residual magnetic flux density of the permanent magnet and also reduces the output of the rotating electrical machine. In addition, the thickness of the magnetization direction of the NdFeB magnet is increased only in order to improve the demagnetization resistance.

  In the permanent magnet type rotating electrical machine of the present embodiment, the Alnico magnet of the permanent magnet 3 is irreversibly magnetized to adjust the amount of interlinkage magnetic flux that becomes a voltage. Therefore, the flux weakening control in which an excessive reverse magnetic field acts on the permanent magnet 4a of the NdFeB magnet is not used. In some cases, weakening control for fine adjustment is used. However, since the current is small, the reverse magnetic field can be extremely small. From this, the permanent magnet type rotating electrical machine of the present embodiment can be applied to a NdFeB magnet having a low coercive force and a high residual magnetic flux density that could not be used for conventional rotating electrical machines due to demagnetization. The air gap magnetic flux density by the NdFeB magnet is increased, and a high output can be obtained.

  For example, the characteristics of a NdFe magnet applied to a conventional rotating electrical machine are coercive force Hcj = 2228 kA / m and residual magnetic flux density Br = 1.23 T, and the characteristics of the NdFeB magnet applied to this embodiment are Hcj = 875 kA / m. The residual magnetic flux density Br = 1.45T. As described above, a magnet having a small coercive force but a magnetic flux density of 1.17 times can be applied, and a high output can be expected about 1.17 times.

  Further, in the conventional rotating electric machine, the thickness of the magnet is increased for demagnetization resistance without contributing to the output. However, since the permanent magnet type rotating electric machine of the present embodiment has a small demagnetizing field, the amount of NdFeB magnet used is increased. Can be reduced. In addition, since it becomes possible to apply an NdFeB magnet with little Dy element added, it can be manufactured stably in the future.

  FIG. 9 is a radial cross-sectional view of the block 20 (or 23) of the rotor 1b of the permanent magnet type rotating electric machine according to the third embodiment of the present invention. The permanent magnet type rotating electrical machine according to the present embodiment includes a rotor 1b shown in FIG. 9 and a stator that accommodates the rotor 1b. In the rotor 1b, a plurality of permanent magnets 4b are provided along the circumferential direction in each of a plurality of rotor cores 2b formed by stacking. Further, the rotor 1b of the present embodiment is divided into a plurality of blocks in the axial direction as in the first and second embodiments, and a plurality of different at least one of shape and magnetic characteristics for each predetermined block. A plurality of permanent magnets of one type selected from the types of permanent magnets are arranged to form a magnetic pole. The permanent magnet 4b is a magnet in which the change in magnetic flux due to magnetization is small and the polarity does not reverse among a plurality of types of permanent magnets, and is installed in a convex shape on the inner diameter side of the rotor 1b to form a magnetic pole. Although not shown, the rotor 1b also has a block provided with a permanent magnet that shows a change in magnetic flux or a reversal of polarity like an alnico magnet. In the block, the alnico magnet is arranged on the q axis in the rotor core 2b in a posture along the radial direction of the rotor 1b.

  As shown in FIG. 9, the plurality of permanent magnets 4b in the present embodiment are installed in a C-shape or V-shape for each magnetic pole in one or more blocks. By making the permanent magnet 4b into a C shape or a V shape, the area of the magnetic pole of the permanent magnet 4b can be increased. Furthermore, by making the permanent magnet 4b into a square shape or a V shape, the magnetic path of the q-axis magnetic flux can be obstructed to reduce the q-axis inductance, thereby improving the power factor of the rotating electrical machine. If the magnetic flux density at the center of the magnetic core 9 is at most about 1.9 T, the magnetic flux distribution in the air gap is not distorted and the magnetic flux of the permanent magnet can be used effectively.

  Even in the present embodiment, an NdFeB magnet with a small amount of Dy element can be adopted as the permanent magnet 4b in which the product of the coercive force and the magnetization direction thickness is large, as in Example 2. A lighter rotating electrical machine with higher output can be realized.

  Further, in the above-described embodiments, the following modifications can be considered.

  (Modification 1) In each of the embodiments 1 to 3, the rotors 1a and 1b are manufactured by inserting and assembling them into the stator, and the magnetic flux generated by the permanent magnet 3 having a small product of the coercive force and the magnetization direction thickness. The permanent magnet 3 can be magnetized so that the magnetic fluxes of the permanent magnets 4a and 4b having a large product of the coercive force and the magnetization direction thickness are opposite to each other on the magnetic pole or air gap surface.

  In order to perform assembly by inserting the magnetized rotors 1a and 1b into the stator in the manufacturing process, it is necessary to take measures against the magnetic attractive force of the permanent magnet. Therefore, as in this example, the amount of magnetic flux of the permanent magnet generated from the rotor 1a (1b) is obtained by magnetizing the magnetic flux of the permanent magnet 3 and the magnetic flux of the permanent magnet 4a (4b) in opposite directions. Can be less. As a result, the magnetic attractive force generated between the rotor 1a (1b) and the stator is reduced, and the assembly workability is improved. Further, when the amount of magnetic flux generated by the permanent magnet 3 and the permanent magnet 4a (4b) is set to 0, the magnetic attractive force is lost, and the work of incorporating the rotor 1a (1b) into the stator can be very easily performed.

  In addition, the rotor 1a is configured such that the front and back surfaces of the rotor core groove are alternately formed for each block. Thereby, dispersion | distribution of the dispersion | variation in the stack of the rotor cores 2a can be made small, and the error of a design dimension can be made small.

  (Modification 2) In each of the embodiments described above, the permanent magnet 4a having a large product of the coercive force and the magnetization direction thickness among the plurality of types of permanent magnets is formed by the permanent magnet 4a at the maximum rotational speed of the rotor 1a. It is assumed that the counter electromotive voltage is equal to or lower than the withstand voltage of the inverter electronic component that is the power source of the permanent magnet type rotating electrical machine.

  The back electromotive force generated by the permanent magnet increases in proportion to the rotation 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, there is a problem that the back electromotive force of the permanent magnet is limited by the withstand voltage 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. there were.

  Therefore, at the time of high speed rotation, the permanent magnet is irreversibly magnetized by the magnetic field in the demagnetizing direction by the negative d-axis current, and the magnetic flux of the permanent magnet 3 is reduced to near zero. Since the counter electromotive voltage generated by the permanent magnet 3 can be reduced to almost zero, the counter electromotive voltage generated by the permanent magnet 4a, which cannot adjust the amount of magnetic flux, may be set to the maximum withstand voltage or less. That is, the amount of magnetic flux of only the permanent magnet 4a of the NdFeB magnet 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 permanent magnet 3 and the permanent magnet 4a magnetized so as to have the maximum amount of magnetic flux can be increased.

  Furthermore, practically, the permanent magnet 3 of the alnico magnet is magnetized in the direction opposite to that at the low speed at the highest speed range, so the total amount of interlinkage magnetic flux is smaller than the interlinkage magnetic flux of only the permanent magnet 4a. Become. That is, in the permanent magnet type rotating electrical machine of this example, the counter electromotive voltage at high speed is smaller than the counter electromotive voltage due to the permanent magnet 4a alone, and the withstand voltage and the allowable maximum rotational speed can be sufficiently afforded. As a result, the configuration of the permanent magnet type rotating electrical machine of Example 2 can suppress the back electromotive voltage during high-speed rotation while maintaining high output and high efficiency during low-speed rotation. Reliability can be increased.

  (Modification 3) In each of the above-described embodiments, the description has been given by taking an example of an 8-pole permanent magnet type rotating electrical machine. However, it is natural that the present invention can be applied to a rotating electrical machine having a number other than 8 poles. Depending on the number of poles, the position and shape of the permanent magnets change somewhat, but the action and effect are obtained in the same way.

  Moreover, in the permanent magnet which forms a magnetic pole, the definition which distinguishes a permanent magnet with the product of a coercive force and the thickness of a magnetization direction is made. Therefore, even if the magnetic poles are formed of the same type of permanent magnet and are formed so as to have different magnetization direction thicknesses, the same operation and effect can be obtained.

  The permanent magnet type rotating electric machine and the permanent magnet type electric motor drive system according to the present invention can be used for a vehicle or the like equipped with the rotating electric machine as a power source.

It is a figure which shows the external appearance of the rotor of the permanent magnet type rotary electric machine of the form of Example 1 of this invention. It is radial direction sectional drawing of the rotor of the permanent magnet type rotary electric machine of the form of Example 1 of this invention. It is radial direction sectional drawing of the rotor of the permanent magnet type rotary electric machine of the form of Example 1 of this invention. It is a BH characteristic figure which shows the magnetic characteristic of the permanent magnet of various materials. It is a figure which shows the direction of the magnetic flux of a permanent magnet when a permanent magnet is irreversibly magnetized so that the linkage magnetic flux with a stator may become the maximum in the permanent magnet type rotary electric machine of the form of Example 1 of this invention. It is a perspective view of the rotor shown with the direction of the magnetic flux of a permanent magnet in case the interlinkage magnetic flux with a stator becomes the maximum in the permanent magnet type rotary electric machine of the form of Example 1 of this invention. The direction of the magnetic flux of the permanent magnet after the demagnetizing magnetic field due to the negative d-axis current is applied so that the flux linkage with the stator is minimized in the permanent magnet type rotating electrical machine according to the first embodiment of the present invention. FIG. It is a perspective view of the rotor shown with the direction of the magnetic flux of a permanent magnet in case the interlinkage magnetic flux with a stator becomes the minimum in the permanent magnet type rotary electric machine of the form of Example 1 of this invention. It is radial direction sectional drawing of the rotor of the permanent magnet type rotary electric machine of the form of Example 3 of this invention. It is radial direction sectional drawing which shows the structure of the rotor of the conventional permanent magnet type rotary electric machine.

Explanation of symbols

1, 1a, 1b Rotor 2, 2a, 2b Rotor core 3, 4, 4a, 4b Permanent magnet 5, 6 Cavity 7, 8 Magnetic barrier 9 Magnetic pole core 10, 11, 12, 13, 14, 15 Flow of magnetic flux 16 cavities 20, 21, 22, 23 blocks

Claims (23)

A stator having an armature winding, and a plurality of permanent magnets along the circumferential direction on each of a plurality of rotor cores arranged to be opposed to each other via an air gap on the inner peripheral side of the stator In a permanent magnet type rotating electrical machine provided with a rotor configured to be divided for each predetermined block in the axial direction,
In the rotor, one type of the plurality of permanent magnets selected from a plurality of types of permanent magnets having at least one of different shapes and magnetic properties is arranged for each predetermined block to form a magnetic pole. Permanent magnet type rotating electrical machine characterized by   The permanent magnet type rotating electric machine according to claim 1, wherein each of the plurality of types of permanent magnets has a magnetization direction different from that of other types of permanent magnets.   The permanent magnet having a small change in magnetic flux due to magnetization among the plurality of types of permanent magnets is installed in a convex shape on the inner diameter side of the rotor to form a magnetic pole. Permanent magnet type rotating electric machine.   The permanent magnet type according to any one of claims 1 to 3, wherein the plurality of permanent magnets are arranged in a C shape or a V shape for each magnetic pole in the one or more blocks. Rotating electric machine.   Among the plurality of rotor cores, a rotor core having a permanent magnet that exhibits a change in magnetic flux or a reversal of polarity due to magnetization is such that the easy magnetization direction of the permanent magnet intersects the radial direction of its own rotor core at right angles. The permanent magnet type rotating electric machine according to any one of claims 1 to 4, wherein the permanent magnet is arranged to form a magnetic pole.   6. The rotor according to claim 1, wherein permanent magnets having a small change in magnetic flux due to magnetization are arranged in blocks located at both axial ends of the divided blocks. The permanent magnet type rotating electric machine described. The permanent magnet type rotating electrical machine according to any one of claims 1 to 6, wherein the rotor is configured such that front and back surfaces of the rotor when the rotor core groove is processed are alternately arranged for each block.   The permanent magnet type according to any one of claims 1 to 7, wherein each of the plurality of types of permanent magnets has a product of a coercive force and a magnetization direction thickness that is different from that of other types of permanent magnets. Rotating electric machine.   9. The permanent magnet rotation according to claim 8, wherein a permanent magnet having a large product of coercive force and magnetization direction thickness among the plurality of types of permanent magnets is an NdFeB-based permanent magnet containing almost no Dy element. Electric.   Among the plurality of types of permanent magnets, the permanent magnet having a large product of coercive force and magnetization direction thickness is the power source of the permanent magnet type rotating electrical machine due to the back electromotive force generated by its own permanent magnet at the maximum rotational speed of the rotor. 10. The permanent magnet type rotating electrical machine according to claim 8, wherein the permanent magnet type rotating electrical machine has a withstand voltage lower than that of the inverter electronic component.   When the rotor is inserted into the stator and assembled, the magnetic flux generated by a permanent magnet having a small product of coercive force and magnetization direction thickness and the magnetic flux generated by a permanent magnet having a large product of coercive force and magnetization direction thickness are magnetic poles or The permanent magnet type rotating electrical machine according to any one of claims 8 to 10, wherein the air gap surfaces are opposite to each other. A permanent magnet type rotating electrical machine according to any one of claims 1 to 11,
An inverter for driving the permanent magnet type rotating electrical machine;
A magnetizing section for passing a magnetizing current for controlling the magnetic flux of the permanent magnet;
A permanent magnet motor drive system comprising:   The magnetizing portion irreversibly changes the amount of magnetic flux of the permanent magnet by magnetizing at least one permanent magnet among the permanent magnets of the rotor in each magnetic pole by a magnetic field generated by passing a current through the armature winding. The permanent magnet motor drive system according to claim 12, wherein the permanent magnet motor drive system is changed.   The magnetizing unit magnetizes at least one permanent magnet among the permanent magnets of the rotor at each magnetic pole by a magnetic field generated by passing an electric current through the armature winding, so that all permanents of the rotor have The permanent magnet motor drive system according to claim 13, wherein the amount of interlinkage magnetic flux of the armature winding by the magnet is set to approximately zero. The rotor is arranged with the plurality of types of permanent magnets so that the magnetic fluxes of the permanent magnets forming the magnetic poles are added together,
The magnetizing unit magnetizes a part of the permanent magnet by a magnetic field generated by passing a current through the armature winding to irreversibly decrease the flux linkage by the permanent magnet, and after the reduction, the magnetic field due to the current is changed to the magnetic field. 15. The permanent magnet motor according to claim 12, wherein the permanent magnet motor is generated in the opposite direction to magnetize a part of the permanent magnet to irreversibly increase the amount of flux linkage. Drive system.   The magnetizing section magnetizes at least one permanent magnet among the permanent magnets of the rotor at each magnetic pole by a magnetic field generated by passing a current through the armature winding, thereby reversing the polarity of the permanent magnet. The permanent magnet motor drive system according to claim 12, The rotor is arranged with the plurality of types of permanent magnets so that the magnetic fluxes of the permanent magnets forming the magnetic poles are added together,
The magnetizing unit magnetizes a part of the permanent magnet by a magnetic field generated by passing a current through the armature winding to reverse the polarity of the permanent magnet, and after the reversal, the magnetic field due to the current is in a direction opposite to the magnetic field. 17. The permanent magnet motor drive system according to claim 16, wherein the permanent magnet motor drive system further generates the original polarity by reversing the polarity of the permanent magnet. A permanent magnet type rotating electrical machine according to any one of claims 8 to 11,
An inverter for driving the permanent magnet type rotating electrical machine;
A magnetizing section for passing a magnetizing current for controlling the magnetic flux of the permanent magnet,
The magnetizing portion causes a current to flow through the armature winding with respect to a permanent magnet having a product of coercive force and magnetization direction thickness smaller than that of other types of permanent magnets among the plurality of types of permanent magnets. A permanent magnet motor drive system characterized by irreversibly changing the amount of magnetic flux of a permanent magnet or reversing the polarity of the permanent magnet.   The magnetizing portion magnetizes a permanent magnet whose product of coercive force and magnetization direction thickness is smaller than the others so that the magnetic flux of the permanent magnet of the magnetic pole is added at the maximum torque of the permanent magnet type rotating electrical machine, and the torque is small In a light load or in a medium-speed rotation region and a high-speed rotation region, the permanent magnet whose product of the coercive force and the magnetization direction thickness is smaller than the other is magnetized by a magnetic field due to current to reduce the magnetic flux, or the magnetic field 19. The permanent magnet motor drive system according to claim 18, wherein the polarity of the permanent magnet is reversed.   The permanent magnet type rotating electrical machine has a permanent magnet with a small product of coercive force and magnetization direction thickness among the magnetic poles, and a permanent magnet with a large product of coercive force and magnetization direction thickness. 20. The permanent magnet electric motor drive system according to claim 18, wherein the permanent magnet motor drive system is substantially equal to or greater than a product of a magnetic field strength and a magnetization direction thickness at an operating point under load.   The magnetizing unit magnetizes the permanent magnet with a magnetic field generated by a d-axis current and irreversibly changes the amount of magnetic flux of the permanent magnet, or reverses the polarity of the permanent magnet with the magnetic field, and further controls the torque by the q-axis current. The permanent magnet motor drive system according to any one of claims 12 to 20, wherein the permanent magnet motor drive system is provided.   The magnetizing unit magnetizes the permanent magnet with a magnetic field generated by a d-axis current and irreversibly changes the amount of magnetic flux of the permanent magnet during the operation of the permanent magnet type rotating electrical machine, or reverses the polarity of the permanent magnet with the magnetic field. 13. The method of selectively performing the operation of causing the magnetic flux generated by the d-axis current and the operation of changing the interlinkage magnetic flux of the armature winding generated by the permanent magnet substantially reversibly by the magnetic flux generated by the d-axis current. The permanent magnet motor drive system according to claim 21.   The rotor is characterized in that each permanent magnet is arranged so that a bias magnetic field acts on the permanent magnet exhibiting a change in magnetic flux or a reversal of polarity in each magnetic pole. The permanent magnet motor drive system according to any one of claims 12 to 22.

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