WO2017014211A1 - Motor - Google Patents

Abstract

This motor includes a stator having a winding, and a rotor. The rotor rotates by being subjected to a rotating magnetic field generated when a drive current is supplied to the winding. The winding includes a first winding and a second winding. The first winding and the second winding are energized with the same timing by the drive current, and are connected in series. The rotor includes magnetic poles comprising permanent magnets, and magnetic flux permitting portions. In a rotor rotational position in which the magnetic poles oppose the first winding, the magnetic flux permitting portions oppose the second winding and permit the generation of an interlinkage magnetic flux arising as a result of a weak field current in the second winding.

Description

motor

The present invention relates to a motor.

Conventionally, a permanent magnet motor such as a brushless motor includes, for example, a stator in which a winding is wound around a stator core and a rotor having a permanent magnet facing the stator as a magnetic pole, as shown in Patent Document 1, for example. The rotor rotates by receiving a rotating magnetic field generated by supplying a drive current to the winding of the stator.

JP 2014-135852 A

In the permanent magnet motor as described above, the higher the rotor is driven, the larger the induced voltage generated in the stator winding due to the increase of the interlinkage magnetic flux by the permanent magnet of the rotor, and this induced voltage decreases the motor output. This hinders high motor rotation.

An object of the present invention is to provide a motor capable of achieving high rotation.

To achieve the above object, a motor according to one aspect of the present invention includes a stator having windings and a rotor. The rotor rotates by receiving a rotating magnetic field generated by supplying a driving current to the winding. The winding includes a first winding and a second winding. The first winding and the second winding are excited at the same timing by the drive current and are connected in series. The rotor includes a magnet magnetic pole having a permanent magnet and a magnetic flux allowing portion. The magnetic flux permitting unit is configured so that the magnetic pole is opposed to the second winding at a rotational position of the rotor facing the first winding, and the interlinkage magnetic flux is generated by the field weakening current in the second winding. Is allowed to occur.

(A) is a top view of the motor which concerns on embodiment of this invention, (b) is a top view of the rotor of Fig.1 (a). It is an electric circuit diagram which shows the connection aspect of the coil | winding of Fig.1 (a). (A) is a graph which shows the change of the induced voltage which arises in U phase winding at the time of rotation of the rotor of Drawing 1 (a), and (b) is the induced voltage which arises in U phase winding at the time of rotor rotation in the conventional composition. It is a graph which shows the change of. It is an electric circuit diagram which shows the connection aspect of the coil | winding in another example. It is a top view of the rotor of the SPM structure in another example. It is a top view of the rotor of the SPM structure in another example. It is a top view of the rotor of the IPM structure in another example. It is a top view of the rotor of the IPM structure in another example. It is a top view of the rotor of the IPM structure in another example. It is a top view of the rotor of the IPM structure in another example. It is a top view of the rotor of the IPM structure in another example. It is a top view of the rotor of the IPM structure in another example. It is a top view of the rotor of the IPM structure in another example. It is a top view of the rotor of the IPM structure in another example. It is a top view of the rotor of the IPM structure in another example. It is a top view of the motor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example. It is a top view of the rotor of another example.

Hereinafter, an embodiment of the motor will be described.
As shown in FIG. 1A, the motor 10 of the present embodiment is configured as a brushless motor, and is configured by arranging a rotor 21 inside an annular stator 11.

[Structure of stator]
The stator 11 includes a stator core 12 and a winding 13 wound around the stator core 12. The stator core 12 is formed of a magnetic metal in a substantially annular shape, and has twelve teeth 12a extending radially inward at equal angular intervals in the circumferential direction.

Twelve windings 13 having the same number as the teeth 12a are provided, and each tooth 12a is wound in the same direction by concentrated winding. That is, twelve windings 13 are provided at equal intervals in the circumferential direction (30 ° intervals). The windings 13 are classified into three phases according to the three-phase driving currents (U phase, V phase, W phase) supplied, and U1, V1, Let W1, U2, V2, W2, U3, V3, W3, U4, V4, and W4.

Referring to each phase, the U-phase windings U1 to U4 are arranged at equal intervals in the circumferential direction (90 ° intervals). Similarly, the V-phase windings V1 to V4 are arranged at equal circumferential intervals (90 ° intervals). Similarly, the W-phase windings W1 to W4 are arranged at equal intervals in the circumferential direction (90 ° intervals).

Further, as shown in FIG. 2, the windings 13 are connected in series for each phase. That is, the U-phase windings U1 to U4, the V-phase windings V1 to V4, and the W-phase windings W1 to W4 each constitute a series circuit. In this embodiment, a series circuit of U-phase windings U1 to U4, a series circuit of V-phase windings V1 to V4, and a series circuit of W-phase windings W1 to W4 are star-connected.

[Configuration of rotor]
As shown in FIG. 1B, the rotor core 22 of the rotor 21 is formed of a magnetic metal in a substantially disk shape, and a rotating shaft 23 is fixed at the center. On the outer peripheral portion of the rotor core 22, there are a magnetic pole pair (magnetic pole set) P composed of an N-pole magnet magnetic pole Mn and an S-pole magnet magnetic pole Ms adjacent in the circumferential direction, and a protrusion 24 integrally formed with the rotor core 22. Are provided alternately in the circumferential direction. In the present embodiment, two magnetic pole pairs P and two protrusions 24 are provided. The two magnetic pole pairs P are provided at 180 ° facing positions in the circumferential direction, and the two protrusions 24 are similarly provided at 180 ° facing positions in the circumferential direction.

The N-pole magnet magnetic pole Mn and the S-pole magnet magnetic pole Ms each have a permanent magnet 25 fixed to the outer peripheral surface of the rotor core 22. That is, the rotor 21 has a surface magnet type structure (SPM structure) in which four permanent magnets 25 are fixed to the outer peripheral surface of the rotor core 22. Each permanent magnet 25 has the same shape, and the outer peripheral surface of each permanent magnet 25 has an arc shape with the axis L as the center when viewed from the direction of the axis L of the rotary shaft 23.

Further, each permanent magnet 25 is formed so that the magnetic orientation faces the radial direction. More specifically, the permanent magnet 25 of the N-pole magnet magnetic pole Mn is magnetized in the radial direction so that the magnetic pole appearing on the outer peripheral side becomes the N-pole, and the permanent magnet 25 of the S-pole magnet magnetic pole Ms has the magnetic pole appearing on the outer peripheral side. It is magnetized in the radial direction so as to be the south pole. Each permanent magnet 25 is, for example, an anisotropic sintered magnet, and includes, for example, a neodymium magnet, a samarium cobalt (SmCo) magnet, an SmFeN-based magnet, a ferrite magnet, an alnico magnet, or the like. Moreover, each permanent magnet 25 is arrange | positioned so that the thing of the same pole may oppose 180 degrees in the circumferential direction. That is, the N-pole magnet magnetic poles Mn are arranged at positions opposite to each other by 180 °. Similarly, the S-pole magnet magnetic poles Ms are arranged at positions opposed to each other by 180 °.

The open angle (occupied angle) around the axis L of each permanent magnet 25 is set to (360 / 2n) °, where n is the total number of magnet magnetic poles Mn and Ms (number of permanent magnets 25). In the present embodiment, since the total number of magnet magnetic poles Mn and Ms is 4, the open angle of each permanent magnet 25 is set to 45 °. Further, the N-pole permanent magnet 25 and the S-pole permanent magnet 25 constituting the magnetic pole pair P are disposed adjacent to each other in the circumferential direction, and the open angle of the magnetic pole pair P is 90 ° for two permanent magnets 25. It has become.

The protrusions 24 of the rotor core 22 are formed to protrude radially outward between the magnetic pole pairs P in the circumferential direction. That is, the protrusion 24 is configured to be adjacent to the N-pole permanent magnet 25 on one side in the circumferential direction and to be adjacent to the S-pole permanent magnet 25 on the other side in the circumferential direction. Further, the outer peripheral surface of each protrusion 24 has an arc shape centered on the axis L as viewed from the direction of the axis L of the rotating shaft 23, and the outer peripheral surface of the protrusion 24 and the outer peripheral surface of the permanent magnet 25 are surfaces. It is comprised so that it may become one.

Also, a gap K is provided between the adjacent permanent magnets 25 at both ends in the circumferential direction of each protrusion 24. The opening angle of each protrusion 24 around the axis L is set smaller than the opening angle (90 °) of the magnetic pole pair P by the amount of the gap K provided.

Next, the operation of this embodiment will be described.
A three-phase drive current (AC) having a phase difference of 120 ° is supplied from a drive circuit (not shown) to the U-phase windings U1 to U4, the V-phase windings V1 to V4, and the W-phase windings W1 to W4, respectively. Then, the windings U1 to W4 are excited at the same timing for each phase to generate a rotating magnetic field in the stator 11, and the rotor 21 rotates based on the rotating magnetic field. At this time, the magnetic poles formed on the stator 11 by the supply of the three-phase drive current are the same for the windings U1 to W4 of each phase. Note that the number of magnetic poles (the number of magnet magnetic poles Mn and Ms) of the rotor 21 of this embodiment is four, but the number of poles of the rotor 21 is set to the magnet magnetic poles Mn and Ms in the windings U1 to W4 of each phase. The drive current set is assumed to be twice the number of (8 poles in this embodiment).

When the rotor 21 rotates at high speed, field weakening control for supplying a field weakening current (d-axis current) to the winding 13 is executed. When the rotor 21 rotates at high speed (field weakening control), for example, as shown in FIG. 1A, when the N-pole magnet magnetic pole Mn is opposed to the U-phase windings U1 and U3 in the radial direction, Protrusion 24 opposes U-phase windings U2 and U4 in the radial direction.

At this time, a field weakening current is supplied to each of the U-phase windings U1 to U4. However, in the U-phase windings U1 and U3, a magnetic flux (radially outward) generated by the opposing N-pole magnet magnetic poles Mn. Magnetic flux) exceeds the interlinkage magnetic flux (interlinkage magnetic flux inward in the radial direction) caused by the field weakening current, and the interlinkage magnetic flux φx that passes outward in the radial direction is generated in the U-phase windings U1 and U3.

On the other hand, in the U-phase windings U2 and U4, the portion of the rotor 21 facing is not the magnet magnetic pole Mn but the protrusion 24 of the rotor core 22, so the interlinkage magnetic flux φy due to the field weakening current does not disappear and the U-phase winding The flux linkage φy passes through the lines U2 and U4 inward in the radial direction. That is, the protrusion 24 of the rotor core 22 facing the U-phase windings U2 and U4 is configured as a magnetic flux allowing portion that allows generation of the interlinkage magnetic flux φy due to the field weakening current. The magnetic flux Mn generates an interlinkage magnetic flux φy having a phase opposite to that of the interlinkage magnetic flux φx generated in the U-phase windings U1 and U3. In each U-phase winding U1 to U4, an induced voltage is generated by the interlinkage magnetic fluxes φx and φy. Note that the above effect also occurs when the S-pole magnet magnetic pole Ms faces the U-phase windings U1 and U3, for example.

Here, FIG. 3A shows the change in the induced voltage generated in the U-phase windings U1 to U4 during the high-speed rotation of the rotor 21 in the present embodiment in a predetermined rotation range (90 °). b) shows changes in the induced voltage generated in the U-phase windings U1 to U4 during high-speed rotation of the rotor in the conventional configuration in a predetermined rotation range (90 °). The conventional configuration is a configuration in which each magnetic pole is uniform in the 8-pole rotor, that is, a configuration in which four N-pole and S-pole permanent magnets are alternately arranged at equal intervals in the circumferential direction.

In the conventional configuration, since the magnetic poles of the rotor are uniform, interlinkage magnetic fluxes in the same direction are generated in the U-phase windings U1 to U4. Therefore, as shown in FIG. 3B, the same induced voltage vx is generated in each of the U-phase windings U1 to U4. When the U-phase windings U1 to U4 are in series, the combined induced voltage vu ′ obtained by synthesizing the induced voltage vx generated in each U-phase winding U1 to U4 is the induced voltage vx of each U-phase winding U1 to U4. (That is, four times the induced voltage vx).

On the other hand, in this embodiment, as described above, the interlinkage magnetic flux generated in the U-phase windings U1 and U3 by the magnet magnetic poles Mn and Ms, for example, in the U-phase windings U2 and U4 facing the protrusion 24 of the rotor core 22. An interlinkage magnetic flux φy having a phase opposite to that of φx is generated. Therefore, as shown in FIG. 3A, the induced voltage vy generated in the U-phase windings U2 and U4 has a reverse polarity (reverse phase) with respect to the induced voltage vx generated in the U-phase windings U1 and U3. . As a result, the combined induced voltage vu (vu = vx × 2 + vy × 2) obtained by combining the induced voltages of the U-phase windings U1 to U4 is combined with the combined induced voltage vu ′ (see FIG. 3B) in the conventional configuration. In comparison, it is effectively reduced.

Here, the combined induced voltage vu of the U-phase windings U1 to U4 has been described as an example, but the V-phase windings V1 to V4 and the W-phase windings W1 to W4 are similarly affected by the protrusions 24 of the rotor core 22. A decrease in the synthesis induced voltage occurs.

Next, characteristic advantages of this embodiment will be described.
(1) The windings 13 of the stator 11 are composed of four U-phase windings U1 to U4, V-phase windings V1 to V4, and W-phase windings W1 to W4, respectively, corresponding to the supplied three-phase driving current. Thus, the four windings of each phase are connected in series. That is, the winding 13 of the stator 11 includes at least two windings (first winding and second winding) connected in series in each phase.

The rotor 21 includes magnet magnetic poles Mn and Ms having permanent magnets 25, and U-phase windings U2 and U4 at a rotational position where the magnetic pole Mn (or magnet magnetic pole Ms) faces, for example, the U-phase windings U1 and U3. And a protruding portion 24 (magnetic flux allowing portion) of the opposing rotor core 22. The protrusion 24 of the rotor core 22 allows the linkage flux φy to be generated by the field weakening current in the opposing winding 13 (for example, the U-phase windings U2 and U4).

According to this configuration, the induced voltage vy generated by the interlinkage magnetic flux φy caused by the field weakening current in the winding 13 facing the protrusion 24 of the rotor core 22 is the winding 13 facing the magnet magnetic pole Mn (or the magnet magnetic pole Ms). The polarity is opposite to that of the induced voltage vx generated in (see FIG. 3A). As a result, the combined induced voltage vu obtained by combining the induced voltages vx and vy can be kept small, and as a result, the motor 10 can be rotated at a high speed.

Note that, in the winding mode in which the windings 13 are connected in series in each phase as in the present embodiment, the sum of the induced voltages generated in the respective windings for each phase becomes the combined induced voltage. The voltage tends to increase. For this reason, by providing the protrusions 24 on the rotor 21 as described above in the configuration in which the windings 13 are in series in each phase, the effect of suppressing the combined induced voltage vu can be obtained more significantly. It is more preferable to increase the rotation speed.

In addition, since the rotor 21 includes the protrusion 24, the field-weakening current supplied to the winding 13 can be suppressed to a small value. Since the field weakening current can be reduced, the permanent magnet 25 is difficult to demagnetize during field weakening control, and the copper loss of the winding 13 can be suppressed. In other words, since the amount of flux linkage that can be reduced with the same amount of field-weakening current increases, higher rotation by field-weakening control can be obtained more effectively.

(2) The magnet magnetic poles Mn and Ms are formed by fixing the permanent magnet 25 to the outer peripheral surface of the rotor core 22. That is, since the rotor 21 has a surface magnet type structure (SPM structure), it can contribute to the high torque of the motor 10.

(3) The protrusion 24 of the rotor core 22 as the magnetic flux allowing portion is formed at the same position as the permanent magnet 25 in the radial direction. According to this configuration, the protrusion 24 (magnetic flux allowing portion) of the rotor core 22 can be opposed to the magnetic poles (the teeth 12a and the windings 13) of the stator 11 at a closer distance. The magnetic resistance (air gap) between the protrusions 24 can be kept small. Thereby, the interlinkage magnetic flux φy generated by the field weakening current can be increased in the winding 13 facing the protrusion 24 of the rotor core 22, and as a result, the combined induced voltage vu can be more suitably suppressed.

(4) A plurality (two sets) of magnetic pole pairs (magnetic pole sets) P each composed of an N-pole magnet magnetic pole Mn and an S-pole magnet magnetic pole Ms arranged adjacent to each other in the circumferential direction are arranged at equal intervals in the circumferential direction. According to this configuration, it is possible to make the rotor 21 have an excellent balance magnetically and mechanically.

In addition, you may change the said embodiment as follows.
In the above embodiment, the windings of each phase, that is, the U-phase windings U1 to U4, the V-phase windings V1 to V4, and the W-phase windings W1 to W4 are connected in series. However, the winding mode may be changed as appropriate.

For example, in the example shown in FIG. 4, in the U phase, the windings U1, U2 are connected in series, and the windings U3, U4 are connected in series, and the series pair of the windings U1, U2 and the windings U3, U4. Are connected in parallel. Similarly, in the V phase, the windings V1 and V2 are connected in series, and the windings V3 and V4 are connected in series. The series pair of the windings V1 and V2 and the series pair of the windings V3 and V4 are parallel. It is connected. Similarly, in the W phase, the windings W1, W2 are connected in series, and the windings W3, W4 are connected in series. The series pair of the windings W1, W2 and the series pair of the windings W3, W4 Are connected in parallel.

When the winding mode of FIG. 4 is applied to the configuration of the rotor 21 of the above-described embodiment (see FIG. 1), for example, in the U phase, the winding U1 and the winding U3 have the same induced voltage (the induced voltage). vx) occurs, and induced voltages (the induced voltages vy) having the same magnitude are generated in the windings U2 and U4. For this reason, the combined induction voltage generated in the series pair of the windings U1 and U2 and the combined induction voltage generated in the series pair of the windings U3 and U4 are substantially equal (vx + vy). As a result, a reduction in the induced voltage due to the provision of the protrusion 24 as the magnetic flux allowing portion always occurs in both the series pair of the windings U1 and U2 and the series pair of the windings U3 and U4. Since the series pair of the windings U1 and U2 and the series pair of the windings U3 and U4 are parallel, the combined induction voltage vu in the entire U-phase winding is the combined induction voltage of the series pair of the windings U1 and U2. (And the combined induction voltage of the series pair of windings U3 and U4) (vx + vy), and the combined induction voltage vu can be effectively suppressed.

Here, when the winding U2 and the winding U3 are exchanged in the example shown in FIG. 4, that is, the windings U1 and U3 having the same magnitude of the induced voltage are connected in series and the magnitude of the induced voltage is the same. Consider the case where the windings U2 and U4 are in series. In this case, the reduction of the induced voltage due to the provision of the protrusion 24 occurs only in one of the series pair of the windings U2 and U4 and the series pair of the windings U1 and U3, and the induced voltage does not decrease on the other side. And since the series pair of winding U1, U3 and the series pair of winding U2, U4 are parallel, it is disadvantageous at the point which suppresses the synthetic | combination induced voltage in the whole U-phase winding effectively. Similarly, when the U-phase windings U1 to U4 are arranged in parallel, similarly, it is disadvantageous in that the combined induced voltage in the entire U-phase winding is effectively suppressed.

As described above, when the windings are arranged in series in each phase, the windings (for example, U-phase windings) respectively facing the magnet magnetic pole Mn (magnet magnetic pole Ms) and the protrusion 24 at a predetermined rotational position of the rotor 21. Line U1 and U-phase winding U2) are connected in series. As a result, the induced voltages of the opposite polarity (reverse phase) generated in the in-phase windings connected in series can be added to obtain a combined induced voltage, and the combined induced voltage in each phase can be effectively suppressed. Can do.

In the example of FIG. 4, in the U phase, the windings U1 and U2 are a series pair and the windings U3 and U4 are a series pair. However, the windings U1 and U4 and the windings U2 and U3 are respectively Similar advantages can be obtained as a series pair. The same change can be made in the V phase and the W phase.

In the example of FIG. 4, in the U phase, the series pair of the windings U1 and U2 and the series pair of the windings U3 and U4 are connected in parallel. However, the present invention is not particularly limited to this, and the winding U1 , U2 and the series pair of windings U3, U4 may be separated, and a pair of inverters may be provided to supply a U-phase drive current to each of the separated series pairs. With this configuration, the same advantages can be obtained. The same change can be made in the V phase and the W phase.

Moreover, in the example shown in the said embodiment (refer FIG. 2) and FIG. 4, although the connection aspect of the coil | winding was made into the star connection, it is not restricted to this, For example, it is good also as a delta connection.
In the above embodiment, the protrusion 24 that protrudes from the rotor core 22 between the circumferential directions of the magnetic pole pair P is provided, but the protrusion 24 is omitted from the rotor 21 of the above embodiment, for example, as shown in FIG. The outer shape of the rotor core 22 may be formed in a circular shape when viewed in the axial direction. In this configuration, the exposed surface 22a on the outer peripheral surface of the rotor core 22 where the permanent magnet 25 is not fixed functions as a magnetic flux allowing portion. With such a configuration, the same advantage as the advantage (1) of the above embodiment can be obtained.

In the rotor 21 of the above-described embodiment, the magnet poles Mn and Ms (permanent magnet 25) are arranged at 180 ° facing positions with the same pole, but it is not particularly limited thereto.
For example, as shown in FIG. 6, magnet magnetic poles Mn and Ms (permanent magnet 25) are alternately provided on the half circumference of the rotor core 22 as N poles and S poles, and the remaining half circumference is configured as a magnetic flux permissible portion (in the figure, the above-mentioned exposure). It may be configured as a surface 22a. With such a configuration, the same advantage as the advantage (1) of the above embodiment can be obtained. In the figure, the exposed surface 22a on the outer periphery of the rotor core 22 is used as a magnetic flux allowing portion. However, the present invention is not limited to this. For example, the protrusion 24 formed integrally with the rotor core 22 as in the above embodiment may be used as the magnetic flux allowing portion. .

The rotor 21 of the above embodiment has an SPM structure in which the permanent magnets 25 constituting the magnet magnetic poles Mn and Ms are fixed to the outer peripheral surface of the rotor core 22. For example, as shown in FIG. An embedded magnet type structure (IPM structure) may be employed in which the permanent magnet 25a is embedded in the inner portion of the surface 22b.

In the example shown in FIG. 7, the outer peripheral surface 22b of the rotor core 22 is circular when viewed in the axial direction, and the radially outer surface and the radially inner surface of each permanent magnet 25a constituting the magnetic poles Mn and Ms are viewed in the axial direction. The arc shape is centered on the central axis of the rotor core 22 (the axis L of the rotary shaft 23). In such a configuration, the portion located in the circumferential direction of the magnetic pole pair P in the rotor core 22 functions as the magnetic flux allowance portion 22c similar to the protrusion 24 of the above embodiment, and thus obtains the same advantages as in the above embodiment. Can do. Furthermore, according to this configuration, the magnet magnetic poles Mn and Ms are advantageous in that the permanent magnet 25a is embedded in the rotor core 22, and therefore the demagnetization of the permanent magnet 25a during field-weakening control is suppressed.

Further, the rotor 21 shown in FIG. 8 is a modification of the configuration shown in FIG. 7, and has the same shape as the magnet accommodation hole 22d of each magnet magnetic pole Mn, Ms and can accommodate a permanent magnet 25a. Two holes 22e are formed in each magnetic flux allowing portion 22c. That is, the rotor core 22 is formed with eight magnet housing holes 22d and 22e in which the permanent magnets 25 can be embedded at equal circumferential intervals (45 ° intervals). According to such a configuration, if the permanent magnet 25a is embedded in the magnet housing hole 22e, the rotor core 22 can be configured as an 8-pole IPM rotor, and the versatility of the rotor core 22 is improved. .

Further, the rotor 21 shown in FIG. 9 is a further modification of the configuration shown in FIG. 7, and each permanent magnet 25a has a rectangular shape when viewed in the axial direction. Each permanent magnet 25 a is provided such that a surface (radial inner surface) including a long side when viewed from the axial direction is orthogonal to the radial direction of the rotor 21. According to such a configuration, each permanent magnet 25a can be formed into a simple rectangular parallelepiped, so that molding is facilitated and it is possible to contribute to a reduction in magnet processing costs. In addition, as in the example shown in FIG. 7, the configuration in which each permanent magnet 25 a has an arc shape when viewed in the axial direction increases the magnet surface area compared to the configuration in which each permanent magnet 25 a has a rectangular shape when viewed in the axial direction. Can contribute to higher torque.

Further, the rotor 21 shown in FIG. 10 is a further modification of the configuration shown in FIG. 7, and each permanent magnet 25a has an arc shape that protrudes radially inward when viewed in the axial direction. According to such a configuration, it is possible to increase the volume of the radially outer portion (outer peripheral core portion 22g) of the permanent magnet 25a in the rotor core 22, so that it is possible to increase the reluctance torque and further increase the reluctance torque. Can contribute to higher torque. In the example shown in FIG. 10, in the rotor core 22 between the opposed end portions of the permanent magnet 25a of the magnetic pole Mn and the permanent magnet 25a of the magnetic pole Ms (position corresponding to the boundary between the magnetic poles Mn and Ms), A hollow portion 22f for suppressing a short-circuit magnetic flux between the permanent magnets 25a is formed.

Further, the rotor 21 shown in FIG. 11 is a further modification of the configuration shown in FIG. 10, and each magnet magnetic pole Mn, Ms has a pair of permanent magnets 31 each having a rectangular parallelepiped shape. In each of the magnetic poles Mn and Ms, the pair of permanent magnets 31 are arranged in the rotor core 22 so as to form a substantially V shape that opens outward in the radial direction, and the magnetic pole center line (straight line L1 in FIG. 11). For reference). The permanent magnets 31 in the N-pole magnet magnetic pole Mn are magnetized so that the N-poles appear on the surfaces facing each other so that the outer peripheral side of the magnet magnetic pole Mn becomes the N-pole. Similarly, each permanent magnet 31 in the S magnetic pole Ms is magnetized so that the S poles appear on the surfaces facing each other so that the outer periphery of the magnet magnetic pole Ms becomes the S pole.

Also with this configuration, it is possible to increase the volume of the outer peripheral core portion 22g on the outer peripheral side of the pair of permanent magnets 31 in each of the magnetic poles Mn and Ms, so that it is possible to increase the reluctance torque and further increase the Can contribute to torque. Furthermore, according to this structure, since each permanent magnet 31 can be made into a simple rectangular parallelepiped, shaping | molding becomes easy and it can contribute to the reduction of magnet processing cost.

Further, the rotor 21 shown in FIG. 12 is a further modification of the configuration shown in FIG. 11, and each magnetic pole pair P includes three permanent magnets 32 a, which are arranged radially about the axis L of the rotating shaft 23. 32b and 32c. These permanent magnets 32a to 32c have the same shape. In each magnetic pole pair P, the permanent magnet 32b located in the middle of the three permanent magnets 32a to 32c extends in the radial direction along the boundary between the N-pole magnet magnetic pole Mn and the S-pole magnet magnetic pole Ms. Yes. The permanent magnet 32b has a magnetic orientation substantially along the circumferential direction of the rotor 21, so that a portion near the magnet magnetic pole Mn in the circumferential direction is an N pole and a portion near the magnet magnetic pole Ms in the circumferential direction is an S pole. Magnetized. The permanent magnets 32a and 32c on both sides in the circumferential direction with respect to the middle permanent magnet 32b are provided symmetrically with respect to the boundary portion (permanent magnet 32b) and are closer to the N-pole magnetic pole Mn from the permanent magnet 32b. The opening angle to the permanent magnet 32a and the opening angle from the permanent magnet 32b to the permanent magnet 32c near the S magnetic pole Ms are set to about 45 °. The permanent magnet 32a is magnetized so that the N pole appears on the surface facing the middle permanent magnet 32b, and the permanent magnet 32c is magnetized so that the S pole appears on the surface facing the middle permanent magnet 32b.

Even with such a configuration, it is possible to increase the volume of the outer peripheral core portion 22g in each of the magnetic poles Mn and Ms, so that it is possible to increase the reluctance torque and contribute to higher torque. Furthermore, according to this configuration, the number of permanent magnets can be reduced as compared with the configuration shown in FIG. 11, which can contribute to a reduction in the number of parts.

Further, the rotor 21 shown in FIG. 13 is a modification of the configuration shown in FIG. 12, and each magnet magnetic pole Mn, Ms is positioned near the outer peripheral surface 22b of the rotor core 22 (the radially outer side of the permanent magnets 32a to 32c). The permanent magnet 32d is embedded in the vicinity of the end portion. The permanent magnets 32d have the same shape and a rectangular parallelepiped shape. The permanent magnet 32d of the N-pole magnet magnetic pole Mn is disposed between the circumferential directions of the radially outer ends of the permanent magnets 32a and 32b, and is magnetized so that the radially outer surface becomes the N-pole. Further, the permanent magnet 32d of the S-pole magnet magnetic pole Ms is arranged between the circumferential directions of the radially outer ends of the permanent magnets 32b and 32c, and is magnetized so that the radially outer surface becomes the S pole. According to such a configuration, the torque of the motor 10 can be increased.

Further, the rotor 21 shown in FIG. 14 is a further modification of the configuration shown in FIG. 12, and the magnetic poles Mn and Ms are embedded in the rotor core 22 near the radially inner ends of the permanent magnets 32a to 32c. The permanent magnet 32e is provided. The permanent magnets 32e have the same shape and a rectangular parallelepiped shape. The permanent magnet 32e of the N-pole magnet magnetic pole Mn is disposed between the circumferential directions of the radially inner ends of the permanent magnets 32a and 32b, and is magnetized so that the radially outer surface is the N-pole. The permanent magnet 32e of the magnetic pole Ms having the S pole is disposed between the circumferential directions of the radially inner ends of the permanent magnets 32b and 32c, and is magnetized so that the radially outer surface is the S pole. According to such a configuration, it is possible to secure the volume of the outer peripheral core portion 22g in each of the magnetic poles Mn and Ms, that is, to ensure the reluctance torque, while increasing the torque by adding the permanent magnet 32e. Further, in this configuration, the magnet torque of each of the magnetic poles Mn and Ms is smaller than that in the configuration shown in FIG. 13, but the induced voltage generated in the winding 13 during the rotation of the rotor can be reduced accordingly.

Further, the rotor 21 shown in FIG. 15 is a further modification of the configuration shown in FIG. 14, and in each magnetic pole pair P, the N pole side and S pole side permanent magnets 32a and 32c are permanent on the magnetic pole boundary. It arrange | positions so that it may become parallel with respect to the magnet 32b. According to such a configuration, the size (magnet surface area) of the permanent magnets 32a to 32c and the size (magnet surface area) of each permanent magnet 32e disposed between the inner ends of the permanent magnets 32a to 32c are ensured. Can contribute to higher torque. In the configuration shown in FIG. 15, a cavity (slit) may be formed instead of each permanent magnet 32 e embedded in the rotor core 22.

In the above embodiment, the total number of magnet magnetic poles Mn and Ms in the rotor 21 is four and the number of windings 13 (slot number) of the stator 11 is twelve. The number of 13 can be appropriately changed according to the configuration. For example, the total number of magnet magnetic poles Mn and Ms and the number of windings 13 so that the relationship between the total number of magnet magnetic poles Mn and Ms and the number of windings 13 is n: 3n (where n is an integer of 2 or more). May be changed as appropriate. If the total number of magnet magnetic poles Mn and Ms is an even number as in the above embodiment, the number of magnet magnetic poles Mn and Ms can be the same, and a magnetically balanced configuration can be achieved.

Further, the relationship between the total number of magnet magnetic poles Mn and Ms and the number of windings 13 is not necessarily n: 3n (where n is an integer of 2 or more). The relationship with the number of lines 13 may be 5:12, 7:12, or the like.

FIG. 16 shows an example of the motor 30 in which the relationship between the total number of magnet magnetic poles Mn and Ms and the number of windings 13 is 5:12. In the example of FIG. 16, the same components as those in the above embodiment are denoted by the same reference numerals, detailed description thereof is omitted, and different portions will be described in detail.

In the motor 30 shown in FIG. 16, the twelve windings 13 of the stator 11 are classified according to the three-phase driving currents (U phase, V phase, W phase) supplied, and in FIG. In this order, U1, bar U2, bar V1, V2, W1, bar W2, bar U1, U2, V1, bar V2, bar W1, W2. In addition, U phase winding bar U1, bar U2, V phase winding bar V1 with respect to U phase windings U1, U2, V phase windings V1, V2 and W phase windings W1, W2 constituted by positive windings. , Bar V2, W-phase winding bar W1, bar W2 are constituted by reverse winding. Further, the U-phase winding U1 and the bar U1 are placed at positions facing each other by 180 °, and similarly, the U-phase winding U2 and the bar U2 are placed at positions facing each other by 180 °. The same applies to the other phases (V phase and W phase).

U-phase windings U1, U2, U1 and U2 are connected in series. Similarly, V-phase windings V1, V2, V1 and V2 are connected in series, and W-phase winding W1. , W2, bar W1, and bar W2 are connected in series. The U-phase windings U1, U2, U1 and U2 are supplied with U-phase drive current. As a result, the reverse winding U-phase winding bars U1 and U2 are always excited with the opposite polarity (reverse phase) with respect to the forward winding U-phase windings U1 and U2, but the excitation timing is the same. . The same applies to the other phases (V phase and W phase). The windings of each phase are supplied with a drive current set by regarding the number of poles of the rotor 21 as twice the number of magnet magnetic poles Mn and Ms (that is, 10 poles in this example).

A magnetic pole set Pa in which three magnet magnetic poles Ms and two magnet magnetic poles Mn are alternately arranged adjacent to each other in the circumferential direction and one protrusion 24 of the rotor core 22 are provided on the outer peripheral portion of the rotor 21 of the motor 30. It has been.

The opening angles around the axis L of the magnet magnetic poles Mn and Ms (permanent magnet 25) are set to be equal to each other. The open angles of the magnetic poles Mn and Ms (permanent magnet 25) are set to (360 / 2n) ° where n is the total number of the magnetic poles Mn and Ms (the number of permanent magnets 25). In this example, since the total number of magnet magnetic poles Mn and Ms is 5, the open angle of the magnet magnetic poles Mn and Ms (permanent magnet 25) is set to 36 °, and the open angle of the magnetic pole set Pa is 180 °. Yes.

In other words, in this example, the magnetic pole set Pa is provided on the half of the outer periphery of the rotor 21, and the protrusion 24 having an open angle of approximately 180 ° is formed on the other half. Thereby, the rotor 21 is configured such that the protrusion 24 is positioned on the opposite side of each magnet magnetic pole Mn, Ms by 180 °. The opening angle of the protrusion 24 of the rotor core 22 is smaller than 180 ° by the gap K between the magnet magnetic pole Ms (permanent magnet 25) adjacent in the circumferential direction.

In the above configuration, when the rotor 21 rotates at high speed (when the field weakening control is performed), for example, when the S-pole magnet magnetic pole Ms faces the U-phase winding U1 in the radial direction, the protrusion 24 of the rotor core 22 is on the opposite side in the circumferential direction. Is opposed to the U-phase winding bar U1 in the radial direction (see FIG. 16). That is, the magnet magnetic pole Ms and the protrusion 24 are simultaneously opposed to the U-phase winding U1 and the bar U1 that are excited in opposite phases (same timing).

At this time, the field weakening current is supplied to the U-phase winding U1 and the bar U1, but in the U-phase winding U1, the magnetic flux (magnetic flux inward in the radial direction) of the opposing magnet magnetic pole Ms is weakened. The flux linkage φx that exceeds the flux linkage caused by the current (linkage flux outward in the radial direction) and passes inward in the radial direction is generated in the U-phase winding U1.

On the other hand, in the U-phase winding bar U1, since the portion of the rotor 21 that is opposed is the protrusion 24 of the rotor core 22, the interlinkage magnetic flux φy due to the field weakening current does not disappear, and the U-phase winding bar U1 has no chain. The cross magnetic flux φy passes toward the outside in the radial direction. That is, the protrusion 24 of the rotor core 22 facing the U-phase winding bar U1 is configured as a magnetic flux allowing portion that allows generation of the interlinkage magnetic flux φy due to the field weakening current. As described above, the magnetic flux My that has the opposite phase to the magnetic flux φx generated in the U-phase winding U1 by the magnet magnetic pole Ms is generated in the U-phase winding bar U1. As a result, the induced voltage generated in the U-phase winding bar U1 by the linkage flux φy is opposite in polarity (reverse phase) to the induced voltage generated in the U-phase winding U1 by the linkage flux φx. The combined induced voltage at the line U1 and the bar U1 can be kept small. As described above, since the combined induction voltage can be suppressed in each phase, the motor 30 can be rotated at a high speed.

Note that the number of magnet magnetic poles Mn and Ms is not limited to the example shown in FIG. 16, and for example, three magnet magnetic poles Mn and two magnet magnetic poles Ms may be configured.
Further, the arrangement of the magnet magnetic poles Mn, Ms and the protrusions 24 in the rotor 21 is not limited to the example shown in FIG. 16, and the protrusion 24 is positioned on the opposite side of the magnet magnetic poles Mn, Ms in the circumferential direction. For example, the configuration may be changed as shown in FIG.

In the configuration of FIG. 17, a protrusion 24 is formed instead of the central magnetic pole Ms in the magnetic pole set Pa of the configuration shown in FIG. 16, and a magnetic pole Mn (N-pole permanent magnet 25) is provided on the opposite side in the circumferential direction. This is a configuration provided. According to this configuration, the same advantages as the configuration shown in FIG. 16 are obtained, and furthermore, the rotor 21 is magnetically and mechanically balanced compared to the configuration shown in FIG. be able to.

Further, in the stator 11, it is not necessary that all the U-phase windings U1, U2, bar U1, and bar U2 are connected in series, and the windings U1, bar U1, and windings U2, U2 are respectively connected in different series. A paired configuration may be used. Moreover, it can change similarly also in V phase and W phase.

FIG. 16 shows an example in which the relationship between the total number of magnet magnetic poles Mn and Ms and the number of windings 13 is 5:12, but the present invention can also be applied to a configuration with 7:12. Further, the present invention can also be applied to a configuration in which the total number of 5:12 (or 7:12) magnetic poles Mn and Ms and the number of windings 13 are each equal.

FIG. 18 shows an example of the rotor 21 in which the relationship between the total number of magnet magnetic poles Mn and Ms and the number of windings 13 is 10:24. In this example, the magnetic pole set Pa in which the N-pole magnet magnetic pole Mn and the S-pole magnet magnetic pole Ms are alternately arranged in the circumferential direction and the protrusion 24 of the rotor core 22 are opened at approximately 90 ° intervals in the circumferential direction. They are alternately arranged at an angle (occupied angle). Thus, by arranging the magnetic pole set Pa and the protrusion 24 in a balanced manner in the circumferential direction, the rotor 21 can be configured to have an excellent balance both magnetically and mechanically.

-The rotor 21 of the said embodiment is good also as an interior magnet type structure (IPM structure) as shown in FIG.
In the example shown in FIG. 19, the permanent magnet 42 is accommodated and fixed in the magnet accommodation hole 41 formed in the rotor core 22 in each magnet magnetic pole Mn and Ms. The magnet accommodation holes 41 are formed side by side in the radial direction at each of the magnetic poles Mn and Ms, and the permanent magnets 42 are accommodated in the respective magnet accommodation holes 41. Each of the magnet housing holes 41 has a curved shape that is convex toward the center (axis line L) of the rotor 21 when viewed from the axial direction. Moreover, each magnet accommodation hole 41 has comprised the curved shape which approaches the axis line L most in the circumferential direction center position of each magnet magnetic pole Mn and Ms seeing from an axial direction. Each permanent magnet 42 provided in each magnet accommodation hole 41 also has a curved shape corresponding to the shape of each magnet accommodation hole 41, and each permanent magnet 42 in the N-pole magnet magnetic pole Mn is curved inside ( The permanent magnet 42 in the magnetic pole Ms of the S pole is magnetized so that the portion on the curved inner side (outer side in the rotor radial direction) becomes the S pole. Yes. In the configuration shown in FIG. 19, the number of the magnet housing holes 41 (permanent magnets 42) arranged in the radial direction in each of the magnetic poles Mn and Ms is three. It may be more than one.

According to such a configuration, in each of the magnetic poles Mn and Ms, the portion between the magnet accommodation holes 41 of the rotor core 22 (the portion R1 between the holes) becomes the q-axis magnetic path, so that the q-axis inductance becomes sufficiently large. Further, in the d-axis magnetic path, each magnet accommodation hole 41 (and the permanent magnet 42) becomes a magnetic resistance, so that the d-axis inductance becomes sufficiently small. As a result, the difference (so-called salient pole ratio) between the q-axis and d-axis inductances can be made large, so that the reluctance torque can be increased, which can contribute to further higher torque.

In the configuration as shown in FIG. 19, each permanent magnet 42 is preferably composed of, for example, a neodymium magnet, a samarium cobalt (SmCo) magnet, an SmFeN magnet, a ferrite magnet, an alnico magnet, or the like. Furthermore, it is preferable that the magnetic characteristics (coercive force and residual magnetic flux density) of the plurality of permanent magnets 42 arranged in the radial direction in the magnet magnetic poles Mn and Ms are different from each other. For example, demagnetization can be suppressed by setting the coercive force of the permanent magnet 42 on the outer peripheral side that is easily influenced by an external magnetic field. On the other hand, since the inner permanent magnet 42 is not easily affected by an external magnetic field, a large coercive force is not required, so that the coercive force can be set small (or the residual magnetic flux density can be increased). Therefore, it is preferable that the coercive force is set to be larger as the permanent magnets 42 arranged in the radial direction are located on the outer peripheral side.

In the example of FIG. 19, one permanent magnet 42 is provided in each magnet accommodation hole 41. However, as shown in FIG. 20, for example, a plurality of permanent magnets 42 accommodated in each magnet accommodation hole 41 are provided in the circumferential direction. You may divide | segment into (two in the same figure). According to this configuration, since the size of each permanent magnet 42 can be reduced, each permanent magnet 42 can be easily formed. In the configuration shown in FIG. 20, the number of magnet receiving holes 41 (permanent magnets 42) arranged in the radial direction in each magnet magnetic pole Mn, Ms is two, but is not limited to this, and one or three It may be more than one.

As shown in FIG. 21, a slit 43 is formed in a portion (magnetic flux allowable portion 22 c) located in the circumferential direction of the magnetic pole pair P in the rotor core 22, and the magnetic flux allowable portion 22 c is a salient pole by the magnetic flux rectifying action of the slit 43. You may comprise so that it may act as 44.

21, in the circumferential direction of the rotor core 22, the occupying angle of the pair of magnetic pole pairs P is approximately 180 °, and the remaining range is configured as a magnetic flux allowing portion 22 c where no magnet is arranged. That is, in the rotor core 22, a pair of magnetic pole pairs P and a pair of magnetic flux allowance portions 22c are alternately configured approximately every 90 ° in the circumferential direction. In addition, the magnet arrangement structure of each magnet magnetic pole Mn and Ms is the same as the structure shown in FIG.

A pair of slit groups 43H including a plurality of (three in the example of FIG. 21) slits 43 arranged in the radial direction is formed in each magnetic flux allowing portion 22c. Each slit 43 of each slit group 43H has a curved shape that is convex toward the center (axis line L) of the rotor 21 when viewed from the axial direction. In the example shown in FIG. 21, each slit 43 of each slit group 43H has the same shape as each magnet accommodation hole 41 in each magnet magnetic pole Mn, Ms. In addition, each slit group 43H is configured such that curved apex portions (portions that are closest to the axis L when viewed in the axial direction) of the slits 43 are arranged along the radial direction. The circumferential center (curved apex portion) of each slit group 43H and the circumferential center of each magnet magnetic pole Mn, Ms are positioned at equal intervals in the circumferential direction (45 ° equal intervals in the example in the figure). Has been. In the configuration shown in FIG. 21, the number of slits 43 in each slit group 43H is three. However, the number of slits 43 is not limited to this, and may be two or four or more.

According to such a configuration, the portion between the slits 43 (the portion R2 between the slits) in the rotor core 22 becomes the q-axis magnetic path, so that the q-axis inductance becomes sufficiently large. Further, in the d-axis magnetic path, each slit 43 becomes a magnetic resistance, so that the d-axis inductance is sufficiently small. Therefore, a large difference (so-called salient pole ratio) between the q-axis and d-axis inductances can be obtained. Thereby, the circumferential center position (that is, the center position between the slit groups 43H adjacent in the circumferential direction) of each magnetic flux allowing portion 22c, the slit group 43H adjacent in the circumferential direction, and the magnetic poles Mn and Ms (magnet housing holes). 41) and the salient pole 44 occurs at the circumferential center position. Then, the reluctance torque can be obtained by each of the salient poles 44, which can contribute to further increase in torque. The salient pole 44 becomes a pole by the magnetic flux rectifying action of each slit 43 formed in the rotor core 22, and is not a magnet magnetic pole having a permanent magnet, and therefore the magnetic flux allowing portion 22 c has the salient pole 44. Even so, the magnetic flux allowing portion 22c functions to allow the generation of the interlinkage magnetic flux φy (see FIG. 1) due to the field weakening current.

In the example shown in FIG. 21, the magnet configuration in each of the magnetic poles Mn and Ms is the configuration shown in FIG. 19, but not limited to this, the configuration shown in FIGS. 20, 7, and 9 to 14 ( (IPM structure) or a configuration (SPM structure) as in the above-described embodiment (FIG. 1).

Further, the shape of each slit 43 in each slit group 43H in FIG. 21 may be changed as shown in FIG. In the configuration shown in FIG. 22, each slit 43 is divided at the center position in the circumferential direction of each slit group 43H. That is, the rotor core 22 is formed with a connecting portion 45 that connects the core portions on both sides in the radial direction of each slit 43 at the center position in the circumferential direction of each slit group 43H. The configuration shown in FIG. 22 is advantageous in that the interlinkage magnetic flux φy caused by the field weakening current can be increased and the rotation speed can be increased as compared with the configuration shown in FIG.

As shown in FIG. 23, the opening angle θ1 (occupied angle) of the magnetic pole pair P composed of the magnet magnetic poles Mn and Ms adjacent in the circumferential direction is larger than the opening angle θ2 (occupied angle) of the magnetic flux allowing portion of the rotor core 22. It may be configured. The opening angle θ1 of the magnetic pole pair P is determined in the S-pole permanent magnet 25 from the circumferential end of the N-pole permanent magnet 25 (magnet magnetic pole Mn) that is not adjacent to the S-pole permanent magnet 25 (magnet magnetic pole Ms). This is the opening angle to the circumferential end that is not adjacent to the N-pole permanent magnet 25. Further, the opening angle θ2 of the magnetic flux allowing portion is an opening angle including the protrusion 24 of the rotor core 22 and the gap K on both sides thereof. In the configuration of this example in which two pairs of magnetic poles P and two protrusions 24 (magnetic flux allowing portions) are provided, θ1 + θ2 = 180 (degrees). According to such a configuration, the opening angle θ1 of the magnetic pole pair P is larger than the opening angle θ2 of the magnetic flux allowing portion of the rotor core 22, which is advantageous in achieving high torque.

In the configuration shown in FIG. 23, the present invention is applied to the SPM structure in which the permanent magnets 25 constituting the magnetic poles Mn and Ms are fixed to the outer peripheral surface of the rotor core 22. However, the present invention is not limited to this. The present invention may be applied to an IPM structure as shown in FIG. The rotor 21 shown in FIG. 24 is obtained by changing the shape and arrangement of the permanent magnets 32a, 32b, and 32c in the configuration shown in FIG. 12, and the open angle θ1 of the magnetic pole pair P ( permanent magnets 32a, 32b, and 32c) is This is advantageous in that it is configured to be larger than the opening angle θ2 of the magnetic flux allowance portion 22c, and the torque can be increased. FIG. 23 shows an example in which the present invention is applied to the IPM structure of FIG. 12, but the present invention can also be applied to the IPM structures shown in FIGS. 7 to 11, FIG. 13, FIG.

24, the permanent magnets 32a, 32b, and 32c have the same plate thickness (width in the short direction as viewed in the axial direction). However, as shown in FIG. The plate thickness of the permanent magnet 32b located in the middle of the magnets 32a to 32c may be thicker than the plate thickness of the other permanent magnets 32a and 32c. On the other hand, as shown in FIG. 26, the plate thickness of the permanent magnets 32a and 32c may be larger than the plate thickness of the permanent magnet 32b located in the middle. As in these configurations, the output characteristics of the motor can be easily adjusted by making the plate thicknesses of the permanent magnets 32a, 32b, and 32c different.

In the above embodiment, the projecting portion 24 constituting the magnetic flux allowing portion is integrally formed with the rotor core 22. That is, although the rotor core 22 is configured as an integral part including the protrusion 24, the present invention is not limited thereto, and the protrusion 24 may be configured as a separate body.

For example, in the configuration shown in FIG. 27, the rotor core 22 includes a core body 51 and a separate core member 52. The core body 51 is formed, for example, from a cold rolled steel plate (SPCC) iron or the like in a substantially cylindrical shape, and the rotating shaft 23 is fixed to the center. The core body 51 includes a pair of first fixing portions 53 to which the permanent magnet 25 is fixed and a pair of second fixing portions 54 to which the separate core member 52 is fixed alternately in the circumferential direction on the outer peripheral surface thereof. ing.

The N-pole permanent magnet 25 and the S-pole permanent magnet 25 adjacent to each other in the circumferential direction are fixed to each first fixing portion 53 of the core body 51. Thus, each first fixing portion 53 of the core body 51 is configured with the same magnetic pole pair P (N-pole magnet magnetic pole Mn and S-pole magnet magnetic pole Ms) as in the above-described embodiment.

The second fixing portions 54 are recessed between the first fixing portions 53 in the circumferential direction so as to be recessed radially inward from the outer peripheral surface of the core body 51. A separate core member 52 is fixed to each second fixing portion 54 by press-fitting or bonding. Each separate core member 52 has a fan shape centered on the axis L of the rotation shaft 23. Each separate core member 52 is made of a material (for example, amorphous metal or permalloy) having a higher magnetic permeability than the core body 51 (for example, iron material).

Each separate core member 52 has its radially inner end fitted into each second fixing portion 54, and the portions other than the fitting portion are from the outer peripheral surface (first fixing portion 53) of the core body 51. Also protrudes radially outward. The portion of each separate core member 52 that protrudes from the core body 51 is adjacent to the N-pole permanent magnet 25 via the gap K on one side in the circumferential direction, and the S-pole permanent magnet 25 and the gap K on the other circumferential side. It is comprised so that it may adjoin via. The opening angle of each separate core member 52 around the axis L is set to be smaller than the opening angle (90 °) of the magnetic pole pair P by the amount of the gap K provided. The separate core member 52 is symmetrical with respect to the center line L2 between the circumferential directions of the magnetic pole pairs P in the axial direction, and the circumferential center line (center line L2) of the separate core member 52 ) And the circumferential center line L3 of the magnetic pole pair P (boundary line between adjacent magnetic poles Mn and Ms) is 90 °. Further, the outer peripheral surface of each separate core member 52 has an arc shape centered on the axis L when viewed from the direction of the axis L of the rotation shaft 23, and the outer peripheral surface of the separate core member 52 and the outer periphery of the permanent magnet 25. The plane is configured to be located on the same circle centered on the axis L.

According to such a configuration, the separate core member 52 functions as a magnetic flux allowing portion, like the protrusion 24 of the above embodiment. That is, the field weakening magnetic flux (linkage magnetic flux generated by application of field weakening current) from the opposing winding 13 passes through the separate core member 52. The opening angle (circumferential width) of the separate core member 52 is desirably set so as to include the magnetic path of the field weakening magnetic flux (d-axis magnetic path Pd). That is, the opening angle of the separate core member 52 is equal to or greater than the angle (45 ° in this example) when the rotor 21 is equally divided by twice the total number of magnet magnetic poles Mn and Ms (8 in this example) in the circumferential direction. It is desirable to set. In the example shown in FIG. 27, the opening angle of the separate core member 52 is set to about 75 ° to 85 °, but is not limited thereto, and may be set to 75 ° or less.

And the separate core member 52 which comprises such a magnetic flux allowance part is comprised as a different body from the core main body 51 which has the magnetic pole pair P (N pole magnetic pole Mn and S pole magnet magnetic pole Ms). . Therefore, the magnetic path of the field weakening magnetic flux (d-axis magnetic path Pd) in the separate core member 52 and the magnetic path of the magnetic poles Mn and Ms in the core body 51 (particularly, one magnetic pole pair P and the other magnetic pole) Interference with the magnetic pole pair P can be suppressed. As a result, the field-weakening magnetic flux can easily pass through the separate core member 52, thereby contributing to further higher rotation.

Further, in the same configuration, the separate core member 52 is made of a material having a higher magnetic permeability than the core body 51, so that the weakened magnetic field flux can be more easily passed through the separate core member 52. As a result, it can contribute to further higher rotation. Further, in the component parts of the rotor core 22, at least the separate core member 52 is made of a material having high magnetic permeability, and the core body 51 is made of an inexpensive material (iron material or the like), thereby suppressing an increase in manufacturing cost. High rotation can be achieved.

In the configuration shown in FIG. 27, the configuration including the separate core member 52 is applied to the surface magnet type structure (SPM structure), but may be applied to an embedded magnet type structure (IPM structure). .
FIG. 28 shows an example of the rotor 21 in which the configuration including the separate core member 52 is applied to the IPM structure. In the rotor 21 shown in FIG. 28, the circumferential positions of the magnet magnetic poles Mn and Ms in the core body 51 are configured in substantially the same manner as the IPM structure described above (for example, see the configuration in FIG. 7).

Each magnet magnetic pole Mn, Ms includes a pair of permanent magnets 61 embedded in the core body 51. In each of the magnetic poles Mn and Ms, the pair of permanent magnets 61 are arranged in a substantially V shape that expands to the outer peripheral side when viewed in the axial direction, and on the magnetic pole center line in the circumferential direction (see the straight line L1 in FIG. 28). On the other hand, they are provided in line symmetry. Each permanent magnet 61 forms a rectangular parallelepiped. In addition, the pair of permanent magnets 61 in each of the magnetic poles Mn and Ms has an angular range when the rotor 21 is equally divided by twice the total number of the magnetic poles Mn and Ms (8 in this example) in the circumferential direction (in this example, (Range of 45 °).

In FIG. 28, the magnetization directions of the permanent magnets 61 of the N-pole magnet magnetic pole Mn and the S-pole magnet magnetic pole Ms are indicated by solid arrows, and the tip end side of the arrow represents the N pole and the base end side of the arrow represents the S pole. ing. As indicated by the arrows, the permanent magnets 61 in the N-pole magnet magnetic pole Mn face each other (surfaces near the magnetic pole center line) so that the outer peripheral portion of the magnet magnetic pole Mn is the N-pole. Is magnetized so that the N pole appears. In addition, each permanent magnet 61 in the magnetic pole Ms of the S pole appears so that the S pole appears on the surfaces facing each other (surface near the magnetic pole center line) so that the outer peripheral side portion of the magnet magnetic pole Ms becomes the S pole. Magnetized.

The core body 51 is formed with a magnetoresistive hole 62 at a position on the inner peripheral side of the pair of permanent magnets 61 in each of the magnetic poles Mn and Ms. Each magnetoresistive hole 62 is a rectangular hole that is long in the radial direction when viewed in the axial direction, and is provided at the center position in the circumferential direction of each of the magnetic poles Mn and Ms. That is, in this example, the distance between the centers of the magnetic resistance holes 62 of the magnet magnetic poles Mn and Ms adjacent in the circumferential direction is set to 45 °. Each magnetoresistive hole 62 penetrates the core body 51 in the axial direction, and each magnetoresistive hole 62 is a gap. Thereby, each magnetoresistive hole 62 suppresses the short circuit of the magnetic flux between the magnet magnetic poles Mn and Ms adjacent in the circumferential direction, and as a result, can contribute to high torque.

Further, gaps K1, K2 are provided on the inner peripheral side and the outer peripheral side of each permanent magnet 61, respectively. Each gap K1, K2 is a part of each magnet accommodation hole 63 which accommodates each permanent magnet 61 formed in the core body 51, and the inner peripheral side surface of each permanent magnet 61 faces each gap K1. The outer peripheral side surface of each permanent magnet 61 is configured to face each gap K2. That is, a gap K1 is provided between the permanent magnet 61 and the radially inner end of the magnet accommodation hole 63, and a gap K2 is provided between the permanent magnet 61 and the radially outer end of the magnet accommodation hole 63. Yes. Then, the magnetic resistance of each of the gaps K1 and K2 causes a short circuit of the magnetic flux in each of the permanent magnets 61 (the magnetic flux of each permanent magnet 61 is short-circuited between its N and S poles via the core body 51). As a result, the torque can be increased.

Between the circumferential directions of each magnetic pole pair P in the core body 51, a fixed recess 64 that is recessed radially inward from the outer peripheral surface of the core body 51 is provided. Both end surfaces in the circumferential direction of the fixed recess 64 have a planar shape along the radial direction, and connecting convex portions 65 projecting in the circumferential direction are formed in the fixed recess 64 on the both end surfaces. Each connecting convex portion 65 has a tapered shape in which the width along the radial direction of the rotor 21 extends from the protruding tip (circumferential tip). In addition, a body-side coupling recess 67 to which the coupling member 66 is coupled is formed at the circumferential central portion on the radially inner side surface of the fixed recess 64.

A separate core member 52 that is a separate body from the core body 51 is fitted in the fixed recess 64. The outer peripheral surface of each separate core member 52 has an arc shape centered on the axis L when viewed from the direction of the axis L of the rotary shaft 23, and the outer peripheral surface of the separate core member 52 and the outer peripheral surface of the core body 51 are Are configured to be flush with each other. Moreover, the circumferential direction both end surfaces of the separate core member 52 have comprised the planar shape along radial direction. The circumferential end surfaces and the radially inner side surface of the separate core member 52 are in contact with the circumferential end surfaces and the radially inner side surface of the fixed recess 64, respectively.

A first connection recess 71 into which the connection protrusion 65 of the core body 51 is fitted is formed on each end surface of the separate core member 52 in the circumferential direction. Each first connection recess 71 has the same shape as the connection protrusion 65 of the core body 51. In addition, a second connection recess 72 to which the connection member 66 is connected is formed at the center in the circumferential direction on the radially inner side surface of the fixed recess 64.

The connecting member 66 is provided across the separate core member 52 and the core main body 51 on the radially inner side of the separate core member 52, and connects the separate core member 52 and the core main body 51. Specifically, the connecting member 66 has a tapered shape in which the circumferential width increases from the radial center to both radial ends. Then, the radially inner half of the connecting member 66 is fitted into the body-side connecting recess 67 of the core body 51, and the radially outer half of the connecting member 66 is fitted into the second connecting recess 72 of the separate core member 52. Has been. In addition, it is preferable that the connection member 66 is comprised with the material (for example, resin, stainless steel, brass, etc.) with larger magnetic resistance than the core main body 51 and the separate core member 52. FIG.

As described above, the coupling protrusions 65 of the core body 51 and the first coupling recesses 71 of the separate core member 52 are fitted, and the coupling member 66 is fitted to the body-side coupling recess 67 and the second coupling recess 72. Accordingly, the separate core member 52 is fixed to the fixing recess 64 of the core body 51. In addition, the separate core member 52 is line-symmetric with respect to the center line L2 between the circumferential directions of the magnetic pole pairs P in the axial direction, and the circumferential core line (center line L2) of the separate core member 52 ) And the circumferential center line L3 of the magnetic pole pair P (boundary line between adjacent magnetic poles Mn and Ms) is 90 °. In the configuration shown in FIG. 28, the inner diameter of the separate core member 52 is about half of the outer diameter of the rotor core 22 (the outer diameter of the core main body 51). You may set to more than half or less than half of the outer diameter of the rotor core 22.

Also in such a configuration, as in the configuration shown in FIG. 7, for example, the portion located between the magnetic pole pairs P in the circumferential direction of the rotor core 22 functions as the magnetic flux allowing portion 22c. In the configuration shown in FIG. 28, a part of the magnetic flux allowing portion 22 c is configured by a separate core member 52. The opening angle (circumferential width) of the separate core member 52 is desirably set so as to include the magnetic path of the field weakening magnetic flux (d-axis magnetic path Pd). That is, it is desirable to set the angle of the rotor 21 equal to or larger than twice the total number of magnet magnetic poles Mn and Ms (8 in this example) in the circumferential direction (45 ° in this example). In the example shown in FIG. 28, the opening angle of the separate core member 52 is set to approximately 45 ° to 50 °, but is not limited thereto, and may be set to 45 ° or less, or 50 ° or more. .

28, the core main body 51 and the separate core member 52 are separated from each other. Therefore, the magnetic path of the field weakening magnetic flux in the separate core member 52 (d-axis magnetic path Pd). And interference with the magnetic paths of the magnetic poles Mn and Ms in the core main body 51 (particularly, the magnetic path of the short-circuit magnetic flux between the one magnetic pole pair P and the other magnetic pole pair P) can be suppressed. Thereby, the field-weakening magnetic flux can easily pass through the separate core member 52 that constitutes a part of the magnetic flux allowing portion 22c, which can contribute to higher rotation.

Also, in the configuration shown in FIG. 28, the separate core member 52 is made of a material having a higher magnetic permeability than the core body 51, so that the weakened field magnetic flux can be more easily passed through the separate core member 52. As a result, it can contribute to further higher rotation. Further, in the component parts of the rotor core 22, at least the separate core member 52 is made of a material having high magnetic permeability, and the core body 51 is made of an inexpensive iron material or the like, so that an increase in manufacturing cost can be suppressed and a high rotation speed can be achieved. Can be achieved.

In addition, in the configuration shown in FIG. 28, the permanent magnet 61 is embedded in the core body 51 in each of the magnetic poles Mn and Ms, similarly to the above-described example of the IPM structure (for example, FIG. 7). This is advantageous in that demagnetization of the permanent magnet 61 is suppressed. Further, in the configuration of the magnet magnetic poles Mn and Ms shown in FIG. 28 (arrangement configuration of the permanent magnet 61), similarly to the configuration shown in FIG. Since the volume of the portion 22g can be increased, the reluctance torque can be increased, which can contribute to higher torque.

In the configuration shown in FIGS. 27 and 28, the separate core member 52 is preferably mainly composed of a material having a magnetization easy axis (a crystal orientation easily magnetized) in the circumferential direction. According to this, the field-weakening magnetic flux can easily pass through the d-axis magnetic path Pd in the separate core member 52, and as a result, it can contribute to further higher rotation.

In the configuration shown in FIGS. 27 and 28, a cylindrical cover member that covers the outer peripheral surface of the rotor 21 may be provided. According to this, it is possible to suppress the separate core member 52 from dropping from the core body 51 by the cover member.

In the above embodiment, the permanent magnet 25 is a sintered magnet, but other than this, for example, a bonded magnet may be used.
In the above embodiment, the rotor 21 is embodied as the inner rotor type motor 10 arranged on the inner side in the radial direction of the stator 11, but is not particularly limited to this, and the outer rotor is arranged on the outer side in the radial direction of the stator. It may be embodied in a type of motor.

In the above embodiment, the present invention is embodied in the radial gap type motor 10 in which the stator 11 and the rotor 21 are opposed to each other in the radial direction. However, the present invention is not particularly limited thereto, and the stator and the rotor are in the axial direction. The present invention may be applied to an axial gap type motor that faces the motor.

-The above-mentioned embodiment and each modification may be combined suitably.

Claims (11)

1. A stator having windings;
   A rotor that rotates in response to a rotating magnetic field generated by supplying a driving current to the winding; and
   The winding includes a first winding and a second winding, and the first winding and the second winding are excited at the same timing by the drive current, and Connected in series,
   The rotor includes a magnet magnetic pole having a permanent magnet, and a magnetic flux allowing portion,
   The magnetic flux permitting unit is configured so that the magnetic pole is opposed to the second winding at a rotational position of the rotor facing the first winding, and the interlinkage magnetic flux is generated by the field weakening current in the second winding. Motor that allows the generation of
2. The motor according to claim 1,
   The magnet magnetic pole is a motor in which the permanent magnet is fixed to an outer peripheral surface of a rotor core.
3. The motor according to claim 2,
   The magnetic flux allowing portion is a motor that is a protrusion of the rotor core formed at the same position as the permanent magnet in the radial direction.
4. The motor according to claim 1,
   The magnet magnetic pole is a motor in which the permanent magnet is embedded in a rotor core.
5. The motor according to claim 4,
   The magnet magnetic pole has a plurality of magnet receiving holes formed in the rotor core,
   The plurality of magnet housing holes are juxtaposed in the radial direction,
   The permanent magnet is accommodated in each of the magnet accommodation holes,
   Each of the magnet housing holes has a curved shape that is convex toward the center of the rotor as viewed in the axial direction.
6. The motor according to any one of claims 1 to 5,
   The magnet magnetic pole is one of a plurality of N pole magnet poles and a plurality of S pole magnet poles;
   The plurality of N-pole magnet magnetic poles and the plurality of S-pole magnet magnetic poles include a plurality of magnetic pole sets,
   Each of the magnetic pole sets includes an N-pole magnet pole and an S-pole magnet pole adjacent to each other in the circumferential direction,
   The motor in which the plurality of magnetic pole groups are arranged at equal intervals in the circumferential direction.
7. The motor according to any one of claims 1 to 6,
   The magnetic flux allowing portion includes a slit formed in the rotor core,
   The motor in which the magnetic flux allowing portion acts as a salient pole by the slit.
8. The motor according to claim 7, wherein
   The slit is one of a plurality of slits;
   The plurality of slits are arranged in the radial direction,
   Each of the plurality of slits has a curved shape that is convex toward the center of the rotor as viewed in the axial direction.
9. The motor according to any one of claims 1 to 8,
   The magnet magnetic pole is one of the N magnetic pole and the S magnetic pole adjacent to each other in the circumferential direction,
   The adjacent N magnetic poles and S magnetic poles constitute a magnetic pole pair,
   A motor in which an opening angle of the magnetic pole pair is larger than an opening angle of the magnetic flux allowing portion.
10. The motor according to any one of claims 1 to 9,
    The rotor core of the rotor includes a core body having the magnet magnetic pole, and a separate core member,
    The separate core member is a separate component connected to the core body, and constitutes at least a part of the magnetic flux allowing portion.
11. The motor according to claim 10, wherein
    The separate core member is a motor made of a material having higher magnetic permeability than the core body.

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