JP7126551B2 - Permanent magnet type rotary electric machine and compressor using the same - Google Patents

Description

The present invention relates to a permanent magnet rotating electric machine having a rotor with permanent magnets and a compressor using the same.

Permanent magnet rotating electric machines are applied to various technical fields such as compressors in air conditioners, refrigerators, and food showcases. Conventionally, in permanent magnet rotating electric machines, concentrated winding is used for the stator windings that serve as the armature windings, and permanent magnets with high magnetic flux density such as neodymium magnets are used for the magnetic fields. Efficiency is being worked on. However, with the increase in output density due to compact size and high efficiency, the influence of the nonlinear magnetic characteristics (magnetic saturation) of the iron core has become noticeable. Iron loss, pulsating torque, electromagnetic excitation force, etc. are increasing.

In order to solve these problems, a permanent magnet type rotating electric machine having an outer rotor has been proposed, for example, as described in Patent Document 1. In Patent Document 1, the rotor has an axle hub and a cylindrical member fixed with bolts, and a magnetic cylinder made by laminating annular silicon steel plates to a predetermined thickness is attached to the cylindrical member along the circumference of the central axis of the permanent magnet. It is fixed with a large number of screws on the (d-axis). A permanent magnet is fixed to the inner peripheral surface of the magnetic cylinder with an adhesive agent so that the thickness in the radial direction of the cylindrical member is reduced at both ends in the circumferential direction of the cylindrical member.

JP-A-10-285891

In the technique described in Patent Document 1, since the central portion of the permanent magnet shape is thick, the magnetomotive force is greater than that at both ends, and because the both ends are thin, the magnetic flux of the rotating magnetic field produced by the stator is generated between the poles. (q-axis) becomes easier to pass through, and the torque, which is approximately proportional to the product of the magnetomotive force of the permanent magnet and the magnetic flux of the rotating magnetic field by the stator, is stabilized, making it possible to reduce the pulsating torque. However, in Patent Document 1, the permanent magnet type rotating electric machine can obtain high efficiency in the medium and low speed range of 1000 min ^-1 to 3000 min ^-1 , but in the high speed range of 7000 min ^-1 to 8000 min ^-1 , the load torque is large, or when the number of armature windings of the motor is increased to increase the inductance, the magnetic flux (q-axis magnetic flux) due to the torque current has a greater effect, so the magnetomotive force distribution of the permanent magnets becomes distorted voltage and current phase increases and the power factor drops. In particular, in Patent Document 1, the magnetomotive force distribution of the permanent magnet is distorted by the q-axis magnetic flux. increases and efficiency decreases. Furthermore, in the high speed range, there is a risk that the permanent magnets fixed with the adhesive may come off. As a result, there arises a problem that the permanent magnet type electric rotating machine cannot be controlled with high torque and high efficiency by a driving device such as an inverter.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a permanent magnet type rotating electric machine that can be controlled with high efficiency even in a high speed range, and a compressor using the same.

In addition to the above, it is another object of the present invention to provide a permanent magnet rotating electrical machine and a compressor using the same that can prevent damage to magnets due to acceleration/deceleration accompanying rotation of the rotor.

In order to achieve the above object, the present invention is characterized by having a stator and a rotor rotatably arranged on the outer peripheral side of the stator, and the stator extends radially outward from the center. The rotor has a plurality of teeth radially provided, and an armature winding wound around the plurality of teeth. and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portions , wherein the rotor includes a shaft of the rotor and a plurality of cylindrical rivets inserted into the plurality of rivet insertion portions. and the axis perpendicular to the d-axis at an electrical angle is the q-axis, the plurality of rivet insertion portions are positioned on the d-axis, and the center lines of the plurality of rivet insertion portions is displaced from the d-axis toward the advance side with respect to the rotation direction of the rotor .

A feature of the present invention is a compressor comprising a compression mechanism for reducing the volume of gas, which is a working fluid, and a permanent magnet type rotating electric machine for driving the compression mechanism, wherein the permanent magnet type rotating electric machine is , a stator, and a rotor rotatably disposed on the outer peripheral side of the stator, the stator having a plurality of teeth radially provided radially outward from the center; an armature winding wound around teeth; the rotor includes a plurality of permanent magnet insertion portions extending in the circumferential direction of the rotor and penetrating the rotor in the axial direction; a plurality of plate-shaped permanent magnets inserted into the magnet insertion portion; and the rotor includes a plurality of rivet insertion portions formed through the rotor in an axial direction thereof, and the plurality of rivet insertion portions. A line connecting the center of rotation of the rotor and the center of the permanent magnet in the circumferential direction is defined as the d-axis, and an axis orthogonal to the d-axis at an electrical angle is q. With respect to the axis, the plurality of rivet insertion portions are positioned on the d-axis, and the center lines of the plurality of rivet insertion portions are shifted from the d-axis toward the advancing side with respect to the rotational direction of the rotor. I have arranged it.

ADVANTAGE OF THE INVENTION According to this invention, the permanent-magnet-type rotary electric machine which can be controlled highly efficiently also in a high-speed range, and a compressor using the same can be provided.

Further, according to the present invention, in addition to the above, it is possible to provide a permanent magnet type rotating electric machine and a compressor using the same that can prevent damage to magnets due to acceleration/deceleration accompanying rotation of the rotor.

Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

1 is a cross-sectional view of a permanent magnet type rotating electric machine according to Embodiment 1 of the present invention; FIG. FIG. 2 is a cross-sectional view showing the shape of the rotor core of the permanent magnet type rotating electrical machine according to Example 1 of the present invention; FIG. 10 is a vector diagram of the permanent magnet type rotating electric machine of the comparative example at low speed and low load torque; FIG. 10 is a vector diagram of the permanent magnet type rotating electric machine of the comparative example at high speed and high load torque; FIG. 2 is a vector diagram of the permanent magnet type rotating electric machine according to the first embodiment of the present invention at high speed and high load torque; 1 shows torque characteristics (solid line) of the permanent magnet type rotating electrical machine according to Example 1 of the present invention. FIG. 7 is a cross-sectional view showing the shape of the rotor core of the permanent magnet type rotating electric machine according to Embodiment 2 of the present invention; FIG. 7 is a cross-sectional view showing the shape of a rotor core of a permanent magnet type rotating electric machine according to Embodiment 3 of the present invention; FIG. 11 is a cross-sectional view of a rotor core shape of a permanent magnet type rotating electric machine according to Embodiment 4 of the present invention; It is a cross-sectional view of a compressor according to Embodiment 5 of the present invention.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 9. FIG. In each figure, the same reference numbers denote the same components or components with similar functions. Also, the permanent magnet type rotary electric machine of each embodiment is composed of a 6-pole rotor and a 9-slot stator. That is, the ratio of the number of rotor poles to the number of stator slots is 2:3. The number of poles of the rotor, the number of slots of the stator, and the ratio thereof are not limited to the values in each embodiment, and the same effect as in each embodiment can be obtained with other values. For example, the number of poles of the rotor may be 4, 8, 10, or the like. The permanent magnet type rotating electric machine in each embodiment is a so-called embedded magnet type rotating electric machine in which permanent magnets are embedded in the rotor core.

In the following description, "axial direction" indicates the rotation axis direction of the rotor, "radial direction" indicates the radial direction of the rotor, and "circumferential direction" indicates the circumferential direction of the rotor.

Embodiment 1 FIG. 1 is a cross-sectional view of a permanent magnet type rotating electrical machine according to Embodiment 1 of the present invention. This cross-sectional view shows a cross-section in a direction perpendicular to the rotation axis (the same applies to FIGS. 2, 6, and 7 described later). The first embodiment operates as a permanent magnet synchronous motor.

As shown in FIG. 1, a permanent magnet type rotary electric machine 1 is composed of a stator 2 and a rotor 3 rotatably arranged on the outer peripheral side of the stator 2 with a predetermined gap (air gap) therebetween. . The rotor 3 is provided with a rotor support member (not shown) having a shaft fixing portion. A stator core 6 is laminated in the axial direction, and the stator 2 includes an annular core back 5 and a plurality of teeth 4 protruding radially outward from the core back 5 . A plurality of teeth 4 are arranged at substantially equal intervals along the circumferential direction. A slot 7 is formed between the teeth 4 adjacent in the circumferential direction, and an armature winding 8 of concentrated winding is wound so as to surround the teeth 4 . That is, the armature winding 8 is wound around the axial center of a plurality of teeth 4 radially arranged from the center of the stator 2 toward the outside in the radial direction, and extends circumferentially along the U-phase of the three-phase winding. A winding 8a, a V-phase winding 8b, and a W-phase winding 8c are arranged with a gap therebetween.

Here, in the permanent magnet type rotary electric machine 1 of the first embodiment, the rotor 3 has 6 poles and the stator 2 has 9 slots, so the slot pitch is 120 degrees in electrical angle. A shaft hole 15 is formed in the center of the stator 2 so that a cylindrical shaft (not shown) penetrates.

In the permanent magnet type rotary electric machine 1 of the first embodiment, when a three-phase AC current is passed through the armature winding 8 composed of the three-phase windings 8a to 8c, a rotating magnetic field is generated. Rotor 3 rotates due to the electromagnetic force acting on permanent magnet 14 and rotor core 12 due to this rotating magnetic field.

In order to reduce iron loss such as eddy current loss generated in the stator core 6 and the rotor core 12 when the permanent magnet type rotating electric machine 1 operates, the stator core 6 and the rotor core 12 are made of silicon steel sheets. It is preferable to construct a laminated body in which a plurality of thin plates made of a magnetic steel plate such as a magnetic steel plate are laminated.

FIG. 2 is a cross-sectional view showing the shape of the rotor core of the permanent magnet type rotary electric machine 1 according to the first embodiment. In FIG. 2, the rotor 3 is configured by laminating rotor cores 12 . In the vicinity of the inner peripheral surface of the rotor core 12, a plurality of permanent magnet insertion portions 13 (having an elongated rectangular shape in cross section) are formed extending in the circumferential direction of the rotor 3 and penetrating the rotor 3 in the axial direction. In Example 1, 6 pieces, which is the number of poles, are formed.

A flat plate-shaped permanent magnet 14 made of a magnetic material such as rare earth neodymium is inserted into each of the plurality of permanent magnet inserting portions 13 . The permanent magnet insertion portion 13 is formed slightly larger than the permanent magnet 14 , and the outer circumference of the permanent magnet 14 is covered with the rotor core 12 . The permanent magnets 14 move through the gaps in the permanent magnet insertion portion 13 due to the acceleration/deceleration associated with the rotation of the rotor 3, but since the periphery is covered with the rotor core 12, the load acting on the permanent magnets 14 is permanent. It is received by the surface of the rotor core 12 in the magnet inserting portion 13 . Therefore, there is no risk of cracks or the like occurring in the rotor core 12 itself. In addition, since the permanent magnets 14 are also in contact with the surface of the rotor core 12 in the permanent magnet insertion portion 13, there is no danger of the permanent magnets 14 being damaged.

Here, in the cross section of the rotor 3 in FIG. 2, the direction of the magnetic flux generated by the magnetic poles of the permanent magnets 14, that is, the d-axis (magnetic flux ), and the axis (the axis between the permanent magnets) that is electrically perpendicular to the d-axis, ie, at an electrical angle, is defined as the q-axis.

In FIG. 2, the rotor core 12 is provided with one permanent magnet 14 per magnetic pole. The cross-sectional shape of the permanent magnet 14 is an elongated rectangular shape like the permanent magnet insertion portion 13, and its longitudinal direction extends in a direction geometrically perpendicular to the d-axis. Further, in the rotor core 12 of the rotor 3 of the first embodiment, a plurality of cylindrical rivet insertion portions 16 are formed penetrating in the axial direction of the rotor on the outer diameter side of the permanent magnet insertion portions 13. (Six, which is the number of poles in the first embodiment) are formed. Cylindrical rivets are inserted into the rivet insertion portions 16 to fasten the axially laminated stator cores 6 . The rivet inserting portion 16 is positioned on the d-axis, and the center lines of the plurality of rivet inserting portions 16 are shifted from the d-axis to suppress the influence of the q-axis magnetic flux as will be described later.

The rotor core 12 of the rotor 3 is recessed radially outward from the inner peripheral surface of the rotor on the q-axis between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnets 14). A recess 11 is provided. This concave portion 11 is positioned on the q-axis and suppresses the influence of the q-axis magnetic flux as will be described later. In addition, the rotor 3, that is, the rotor core 12 is located on the inner peripheral side of the recess 11, and the inner peripheral portion where the gap length (clearance) between the stator 2 and the teeth 4 is g1, which is the shortest, and the gap and an inner peripheral portion having a length g2 longer than g1.

Next, the configuration of the recess 11 will be described. The concave portion 11 has two linear portions 11b and 11c parallel to the circumferential length direction of the permanent magnet 14, and a curved portion 11a connecting the rotor inner peripheral side ends of the two linear portions 11b and 11c. ing. By providing the curved portion 11a in the concave portion 11 in this manner, the influence of the stress associated with the centrifugal force of the rotor can be alleviated in the high speed range. In the concave portion 11 of this embodiment, the curved portion 11a is smoothly connected to the two straight portions 11b and 11c. As a result, concentration of stress due to the centrifugal force of the rotor in the concave portion 11 is alleviated, so that the strength of the rotor against the centrifugal force is improved.

Around the rotation center O of the rotor 3, the angle between the ends of the inner peripheral magnetic pole faces of the permanent magnets 14 constituting one magnetic pole of the rotor 3 is θp1, and the two linear portions 11b and 11c of the recess 11 are When the angle between the ends (curved portion 11a) on the outer peripheral side of the rotor is θp2, θp1 and θp2 are set so as to satisfy the relationship θp2/θp1≦0.5.

Here, in this embodiment, as described above, the slot pitch in the stator having the windings of concentrated winding is 120 degrees in electrical angle. Also, since there are 1.5 slots per magnetic pole (=9 slots/6 poles), the angle between the q-axes is 180 degrees in electrical angle. Therefore, the electrical angles are 120°≦θp1<180° and 0°<θp2≦60°. Therefore, 0<θp2/θp1≦0.5 (=60°/120°). In this embodiment, the lower limit is set to 0.18, which is set so as to satisfy the relationship 0.18≤θp2/θp1≤0.5.

Furthermore, according to the study of the present invention, in the case of a rotor provided with concave portions 11 having curved portions as in the present embodiment, by setting 0.18≦θp2/θp1, as shown in FIG. 5 to be described later, , a substantial torque improvement effect in the high-speed region can be obtained by suppressing the q-axis magnetic flux.

The rotor core 12 of the rotor 3 of the first embodiment has recesses radially outward from the inner peripheral surface of the rotor between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnets 14). A recess 11 is provided. The concave portion 11 is positioned on the q-axis. An air layer is formed by the concave portion 11, and the air layer increases the magnetic resistance, making it difficult for magnetic flux to pass between the circumferentially adjacent permanent magnet insertion portions 13 (permanent magnets 14). Therefore, it is possible to reduce the leakage magnetic flux from between the permanent magnets 14, suppress the influence of the q-axis magnetic flux, and reduce the harmonic magnetic flux generated by the interaction between the induced electromotive force and the armature current. That is, the armature reaction is suppressed by the concave portion 11, and the harmonic components of the in-machine magnetic flux are reduced.

Next, a configuration for further enhancing the effect of the first embodiment will be described. The rotor 3 includes notches 17 formed between the permanent magnet insertion portions 13 (permanent magnets 14 ) adjacent in the circumferential direction and separated from the permanent magnet insertion portions 13 . The notch 17 axially penetrates the rotor.

An air layer is formed by the notch 17, and the air layer increases the magnetic resistance, making it difficult for magnetic flux to pass between the circumferentially adjacent permanent magnet insertion portions 13 (permanent magnets 14). A notch 17 is positioned on the q-axis. Therefore, it is possible to reduce the leakage magnetic flux from between the permanent magnets 14, suppress the influence of the q-axis magnetic flux, and reduce the harmonic magnetic flux generated by the interaction between the induced electromotive force and the armature current. That is, the notch 17 suppresses the armature reaction and reduces the harmonic components of the in-machine magnetic flux. In addition, since the outer circumference of the permanent magnets 14 embedded in the permanent magnet insertion portion 13 is covered with the rotor core 12, the permanent magnets 14 move through the clearance of the permanent magnet insertion portion 13 due to the acceleration/deceleration accompanying the rotation of the rotor 3. Even if the rotor core 12 is moved, there is no possibility that the rotor core 12 itself will crack or the like, and there is no possibility that the permanent magnets 14 will be damaged.

Further, the magnetic flux in the rivet insertion portion 16 changes depending on whether it is under no load (when no current is flowing) or under load (when current is flowing). For example, when the center of the rivet insertion portion 16 is aligned with the d-axis, the magnetic flux flows substantially symmetrically to the left and right in the circumferential direction around the rivet insertion portion 16 under no load. On the other hand, under load, the magnetic flux does not flow almost symmetrically to the left and right in the circumferential direction around the rivet insertion portion 16, and the magnetic flux flow is asymmetrical, biased toward the lagging side from the d-axis.

Considering that the magnetomotive force distribution of the permanent magnet 14 is distorted by the influence of the q-axis magnetic flux, the rivet insertion portion 16 of this embodiment is shifted from the d-axis toward the leading side with respect to the rotation direction of the rotor 3. are placed. That is, the position to be shifted from the d-axis is naturally determined from the values of the rotation speed, torque current and q-axis inductance.

3a and 3b are vector diagrams of a permanent magnet type rotating electric machine as a comparative example according to the conventional invention. FIG. 3a is for low speed and low load torque, and FIG. 3b is for high speed and high load torque. The vector diagrams of FIGS. 3a and 3b use a dq-axis coordinate system for controlling a permanent magnet rotating electric machine, and the d-axis direction of this coordinate system corresponds to the d-axis direction of the rotor (see FIG. 2 ).

3a and 3b, Φm indicates the magnetic flux of the rotor in the d-axis direction of the permanent magnet 14. In FIG. Φd and Φq indicate the magnetic flux due to the d-axis component and the q-axis component of the armature current I1 flowing through the stator winding, that is, the d-axis magnetic flux and the q-axis magnetic flux, respectively, in this coordinate system. Φ1 indicates the magnetic flux of the entire permanent magnet type rotating electric machine, that is, the main magnetic flux, which is composed of the magnetic flux Φm due to the permanent magnet and the magnetic flux (Φd, Φq) due to the armature current I1. Also, Em indicates the induced voltage under no load. V1 indicates the terminal voltage of the stator winding, which has a phase difference of 90° with respect to the main magnetic flux Φ1. V1 is represented by a composite vector of the induced voltage Em and the voltage drop (ωΦd, ωΦq: ω is the output angular frequency of the inverter) due to the d-axis component and the q-axis component of the armature current I1.

As shown in FIG. 3a, at low speed and low load torque, since the armature current I1 and its q-axis component are small, the q-axis magnetic flux is small, so the phase difference between the main magnetic flux Φ1 and the magnetic flux Φm of the permanent magnets is small. Therefore, even in the system of Patent Document 1, the power factor is relatively high, and the desired torque can be obtained with high efficiency.

However, as shown in FIG. 3b, at high speed and high load torque, the armature current I1 and its q-axis magnetic flux increase, so the phase difference between the main magnetic fluxes Φ1 and Φm increases. As a result, the power factor decreases, and although the armature current I1 is increased, the torque does not increase, resulting in a decrease in efficiency.

FIG. 4 is a vector diagram of the permanent magnet type rotating electric machine of the first embodiment. FIG. 4 shows the operation at high speed and high load torque. In order to make the effects of the first embodiment easier to understand, the vector diagram of the comparative example shown in FIG. 3b is also shown.

As shown in FIG. 4, in this embodiment, by providing the rotor 3 with the recesses 11 and the cutouts 17, the magnetic resistance of the rotor in the q-axis direction increases. can suppress the influence of the q-axis magnetic flux Φq. In addition, considering the influence of the q-axis magnetic flux Φq, the position of the rivet insertion portion 16 on the d-axis is optimized to improve the magnetomotive force distribution of the permanent magnet 14 . Therefore, even at high speed and high load torque, the power factor is suppressed from being lowered, and a desired torque can be obtained while maintaining a relatively high efficiency.

Here, the configuration of the concave portion 11 and the notch portion 17, which are means for increasing the magnetic resistance in the q-axis direction, that is, means for reducing the q-axis magnetic flux, in the first embodiment will be described in more detail.

As shown in FIG. 2, the gap length g2 between the radially inner peripheral end of the recess 11 in which the rotor 3 is formed on the q-axis and the teeth 4 of the stator 2 is the gap length on the d-axis side. It is set to be greater than g1. That is, the recess 11 on the inner circumference of the rotor 3 has a portion with the shortest gap length g1 with respect to the teeth 4 of the stator 2 and a portion with a longer gap length g2 than g1. . Further, as shown in FIG. 2, the recess 11 includes two straight portions (11b, 11c) parallel to the length direction of the permanent magnet 14 in the circumferential direction, and each end of the straight portions on the inner peripheral side of the rotor. and a curved portion (11a) connecting Thus, the inner peripheral portion of the rotor 3 is constructed.

Further, in the concave portion 11, the curved portion 11a on the inner peripheral side positioned along the rotation direction between the adjacent permanent magnets 14, and the curved portion 11a on the inner peripheral side from the side end in the rotation direction to the rotation direction side. A substantially linear straight portion 11b on the side of the rotation direction that spreads to the outside, and a substantially straight straight portion 11b that spreads in the opposite direction from the end of the curved portion 11a on the inner peripheral side on the side opposite to the rotation direction. It connects with the linear portion 11c on the rotational direction side. That is, the distance between the central portion of the curved portion 11a of the concave portion 11 and the rotation center O is longer than the distance between the permanent magnet 14 and the rotation center O. This reduces the q-axis magnetic flux. In addition, although clockwise rotation is explained here, the rotor 3 may rotate counterclockwise. The magnetic flux of the permanent magnet 14 can be concentrated in the vicinity of the d-axis by the concave portion 11 and the notch portion 17 described above.

In this embodiment, the concave portion 11 is formed by two linear portions (11b, 11c) parallel to the circumferential length direction of the permanent magnet 14 and curved lines connecting the ends of the linear portions on the rotor inner peripheral side. However, it is not limited to this, and any shape that expands to the left and right from the inner peripheral side of the recess 11 toward the outer peripheral side may be used.

As described above, the angle θp1 between the ends of the inner peripheral magnetic pole faces of the permanent magnets 14 constituting one magnetic pole of the rotor 3 and the angle θp1 between the two linear portions 11b and 11c of the recess 11 on the inner peripheral side of the rotor are The angle θp2 between the ends is set so that 0.18≦θp2/θp1≦0.5, and the side surface of the permanent magnet insertion portion 13 (permanent magnet 14) penetrates the rotor 3 in the axial direction. By forming the cutout portion 17 for increasing the magnetic resistance of the q-axis. Therefore, as shown in FIG. 4, the phase difference between the voltage (V1') and the current (I1') and the phase difference between the main magnetic flux Φ1 and the permanent magnet magnetic flux Φm are reduced. As a result, high torque can be obtained in the high speed range. In addition, when the inductance of the permanent magnet type rotating electric machine is large, it is possible to suppress the reduction in power factor due to the influence of the armature reaction. As a result, it is possible to make the permanent magnet type rotary electric machine smaller and more efficient while suppressing a decrease in torque.

FIG. 5 shows torque characteristics (solid line) of the permanent magnet type rotating electric machine of the first embodiment. The vertical and horizontal axes are torque and armature current, respectively. However, if the rated current is 1P. U.S.A. and 1P. U.S.A. and As a comparative example, a dashed line indicates the torque characteristics of a conventional permanent magnet type rotary electric machine. As shown in FIG. 5, the torque of the permanent magnet type rotary electric machine of the first embodiment is larger than that of the comparative example according to the conventional invention, especially in the high speed range.

According to the first embodiment, the recesses 11 that are recessed radially outward from the inner peripheral surface of the rotor 3 are provided between the adjacent permanent magnet inserting portions 13 (between the poles of the permanent magnets 14). Since the concave portion 11 is positioned on the q-axis, power factor reduction due to armature reaction is suppressed, and torque reduction in the high speed region can be suppressed. Therefore, it is possible to improve the efficiency and reduce the size of the permanent magnet type rotating electric machine.

Further, according to the first embodiment, the cutout portion 17 formed separately from the permanent magnet insertion portion 13 is provided between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnets 14). Since the notch portion 17 is positioned on the q-axis, a decrease in power factor due to the influence of the armature reaction is suppressed, and a decrease in torque in the high speed range can be suppressed. Therefore, it is possible to improve the efficiency and reduce the size of the permanent magnet type rotating electric machine.

Further, according to the first embodiment, since the rivet insertion portion 16 is positioned on the d-axis and the center lines of the plurality of rivet insertion portions 16 are shifted from the d-axis, the influence of the armature reaction This suppresses the reduction in power factor due to this, and suppresses the reduction in torque in the high-speed range. Therefore, it is possible to improve the efficiency and reduce the size of the permanent magnet type rotating electric machine.

In the first embodiment described above, both the recess 11 and the notch 17 are provided in the rotor 3, but either the recess 11 or the notch 17 may be provided.

FIG. 6 is a cross-sectional view of the shape of the rotor core of the permanent magnet type rotating electric machine according to the second embodiment of the present invention.

In FIG. 6, those having the same reference numbers as those in FIG. 2 indicate the same components or components having similar functions. Hereinafter, points different from the first embodiment will be mainly described.

Unlike the first embodiment (FIG. 2), the second embodiment has two permanent magnets per magnetic pole of the rotor 3 . When permanent magnets are used as in the first embodiment, heat loss due to eddy currents becomes a problem. In particular, when rotating at a high speed, the frequency and fluctuation width of the fluctuating magnetic field applied to the magnets also increase, resulting in an increase in heat loss. In order to reduce the heat loss due to this eddy current, in this embodiment, the permanent magnets 14 embedded in the permanent magnet insertion portion 13 are divided (14a, 14b). The divided permanent magnets 14a and 14b reduce the magnetic flux interlinking each magnet. Therefore, the eddy current densities of the divided individual permanent magnets 14a and 14b are reduced, and the total amount of eddy current loss is reduced.

According to the second embodiment, since the permanent magnets 14 (14a, 14b) embedded in the permanent magnet insertion portion 13 are divided and arranged, the loss due to eddy current can be reduced.

Further, according to the second embodiment, recesses 11 that are recessed radially outward from the inner peripheral surface of the rotor 3 are provided between the adjacent permanent magnet inserting portions 13 (between the poles of the permanent magnets 14). Since the concave portion 11 is positioned on the q-axis, the power factor drop due to the armature reaction is suppressed, and the torque drop in the high speed region can be suppressed.

Further, according to the second embodiment, the notch portion 17 is provided between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnets 14) so as to be separated from the permanent magnet insertion portions 13. Since the cutout portion 17 is positioned on the q-axis, a decrease in power factor due to the influence of the armature reaction can be suppressed, and a decrease in torque in the high speed range can be suppressed. Therefore, it is possible to improve the efficiency and reduce the size of the permanent magnet type rotating electric machine.

Further, according to the second embodiment, as in the first embodiment, the rivet insertion portions 16 are positioned on the d-axis, and the center lines of the plurality of rivet insertion portions 16 are shifted from the d-axis. , the reduction in power factor due to the influence of the armature reaction is suppressed, and the torque reduction in the high speed range can be suppressed. Therefore, it is possible to improve the efficiency and reduce the size of the permanent magnet type rotating electric machine.

Even in the rotor structure in which the permanent magnets 14 are divided and arranged in this way, it is possible to improve the reduction in power factor due to the influence of the armature reaction, to suppress the reduction in torque, and to make the rotor compact and highly efficient. do not have.

In the second embodiment described above, both the recess 11 and the notch 17 are provided in the rotor 3, but either the recess 11 or the notch 17 may be provided.

FIG. 7 is a cross-sectional view of the shape of the rotor core of the permanent magnet type rotating electric machine according to Embodiment 2 of the present invention.

In FIG. 7, those having the same reference numbers as those in FIG. 2 indicate the same components or components having similar functions. Hereinafter, points different from the first embodiment will be mainly described.

In the third embodiment, unlike the first embodiment (FIG. 2), the center lines of the plurality of rivet insertion portions 16 are the same as the d-axis, and are arranged only at the north pole or the south pole. If the rivet inserts 16 are used as in the prior art, the same number as the permanent magnets 14 are required, resulting in a cost problem. Therefore, in this embodiment, the rivet insertion portion 16 is arranged for each N pole (or S pole).

According to the third embodiment, the distorted degree (location) of the magnetic flux distribution of the permanent magnet due to the rivet insertion portion 16 is reduced, so that the power factor reduction due to the influence of the armature reaction is suppressed, and the torque drop in the high speed range is suppressed. be able to. Therefore, it is possible to improve the efficiency and reduce the size of the permanent magnet type rotating electric machine.

Further, according to the third embodiment, recesses 11 that are recessed radially outward from the inner peripheral surface of the rotor 3 are provided between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnets 14). Since the concave portion 11 is positioned on the q-axis, the power factor drop due to the armature reaction is suppressed, and the torque drop in the high speed region can be suppressed.

Further, according to the third embodiment, the notch portion 17 is provided between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnets 14) so as to be separated from the permanent magnet insertion portions 13. Since the notch portion 17 is positioned on the q-axis, a decrease in power factor due to the influence of the armature reaction is suppressed, and a decrease in torque in the high speed range can be suppressed. Therefore, it is possible to improve the efficiency and reduce the size of the permanent magnet type rotating electric machine.

It goes without saying that even in the rotor structure in which the rivet inserting portions 16 are arranged in this way, the reduction in power factor due to the influence of the armature reaction can be improved, the reduction in torque can be suppressed, and the size and efficiency can be reduced.

In the third embodiment described above, both the recess 11 and the notch 17 are provided in the rotor 3, but either the recess 11 or the notch 17 may be provided.

Embodiment 4 FIG. 8 is a cross-sectional view of a rotor core shape of a permanent magnet type rotating electric machine according to Embodiment 4 of the present invention.

In FIG. 8, those having the same reference numbers as those in FIG. 2 indicate the same components or components having similar functions. Hereinafter, points different from the first embodiment will be mainly described.

In FIG. 8, the line (broken line in the figure) connecting the rotation center O of the rotor 3 and the circumferential corner portion 14a (the corner portion on the outer peripheral side) of the permanent magnet 14 is L1. In the fourth embodiment, unlike the first embodiment (FIG. 2), the center lines of the plurality of rivet insertion portions 16 are aligned with the line L1 connecting the rotation center O of the rotor 3 and the circumferential corners of the permanent magnets 14. placed like this.

According to the fourth embodiment, the distorted degree (location) of the magnetic flux distribution of the permanent magnet due to the rivet insertion portion 16 is reduced, so the power factor reduction due to the armature reaction is suppressed, and the torque drop in the high speed range is suppressed. be able to. Therefore, it is possible to improve the efficiency and reduce the size of the permanent magnet type rotating electric machine.

The position of the rivet inserting portion 16 may be appropriately set according to the specifications of the permanent magnet type rotary electric machine. Considering the first embodiment, the following range should be set. That is, the plurality of rivet insertion portions 16 are positioned on the d-axis such that the center lines of the plurality of rivet insertion portions 16 are deviated from the d-axis, and the center lines of the plurality of rivet insertion portions are the rotation center of the rotor 3. It is arranged so as to be within the range of the position coinciding with the line connecting O and the circumferential corner portion 14 a of the permanent magnet 14 .

Next, an example in which the permanent magnet type rotary electric machines of Embodiments 1 to 4 are applied to a scroll compressor will be described with reference to FIG. FIG. 9 is a cross-sectional view of a compressor according to Embodiment 5 of the present invention.

9, in a cylindrical compression container 69, a spiral wrap 62 standing upright on the end plate 61 of the fixed scroll member 60 and a spiral wrap 65 standing upright on the end plate 64 of the orbiting scroll member 63 are engaged with each other. A compression mechanism is provided, and a compression operation is performed by orbiting the orbiting scroll member 63 via a crankshaft 72 by means of a permanent magnet type rotating electric machine. Any one of the first to fourth embodiments of the present invention is applied as this permanent magnet type rotating electric machine.

Further, of the compression chambers 66a to 66b formed by the fixed scroll member 60 and the orbiting scroll member 63, the compression chamber located on the outermost diameter side moves between the fixed scroll member 60 and the orbiting scroll member 63 as the orbiting motion proceeds. moving toward the center of the , gradually shrinking in volume. When the compression chambers 66 a and 66 b reach near the center of the fixed scroll member 60 and orbiting scroll member 63 , the compressed gas, which is the working fluid in both compression chambers, is discharged from a discharge port 67 communicating with the compression chamber 66 . The discharged compressed gas passes through a gas passage (not shown) provided in the fixed scroll member 60 and the frame 68, reaches the compression vessel 69 below the frame 68, is provided on the side wall of the compression vessel 69, and flows through the discharge pipe 70. is discharged out of the compressor.

A permanent-magnet rotating electrical machine that drives the compressor is controlled by a separate inverter (not shown) and rotates at a rotational speed suitable for compression operation. Here, the permanent magnet type rotary electric machine is composed of the stator 2 and the rotor 3, and the crankshaft 72 is attached to the shaft hole 15 in any one of the first to fourth embodiments. When the crankshaft 72 is rotated by the permanent magnet type rotating electric machine, the orbiting scroll member 63 performs orbital motion with a radius of a predetermined eccentricity above the crankshaft 72 without rotating on its own axis. An oil hole 74 is provided inside the crankshaft 72, and as the crankshaft 72 rotates, the lubricating oil in the oil reservoir 73 below the compression vessel 69 is supplied to the slide bearing 75 through the oil hole 74. be. By applying the permanent magnet type rotary electric machine according to any one of the first to fourth embodiments to such a compressor, the efficiency of the compressor can be improved and energy saving can be achieved.

By the way, many of the current home and commercial air conditioners have R410A refrigerant sealed in the compression vessel 69, and the ambient temperature of the permanent magnet type rotating electric machine is often 80° C. or higher. In the future, if the use of R32 refrigerant, which has a smaller global warming potential, is promoted, the ambient temperature of the permanent magnet type rotating electric machine will further rise. When the temperature of the permanent magnet 14, especially the neodymium magnet, becomes high, the residual magnetic flux density decreases and the armature current increases to ensure the same output. Efficiency reduction can be suppressed by applying the permanent magnet type rotating electric machine.

In the fifth embodiment, an example in which the permanent magnet type rotary electric machine according to any one of the first to fourth embodiments is applied to the scroll compressor has been described. It is not limited. As for the type of compressor, the example of the scroll compressor was explained in the fifth embodiment, but it is also possible to apply to compressors having other compression mechanisms such as rotary compressors and reciprocating compressors. .

According to the fifth embodiment, it is possible to realize a compressor capable of saving energy by applying a small and highly efficient permanent magnet type rotating electric machine. Further, by applying the permanent magnet type rotary electric machine according to any one of the first to fourth embodiments, the operating range can be widened, such as enabling high-speed operation of the compressor.

Furthermore, in refrigerants such as He and R32, compared to refrigerants such as R22, R407C, and R410A, leakage from the gaps in the compressor is large, and especially at low speed operation, the ratio of leakage to the circulation amount is large. decreases. In order to improve efficiency at low circulation rate (low speed operation), it is effective to reduce leakage loss by downsizing the compression mechanism and increasing the rotation speed to obtain the same circulation rate. Furthermore, it is preferable to increase the maximum number of revolutions in order to secure the maximum circulation amount. In contrast, by applying the permanent magnet type rotary electric machine 1 of any one of the first to fourth embodiments to a compressor, it becomes possible to increase the maximum torque and the maximum number of rotations, and at the high speed range, can be reduced, the efficiency can be improved when a refrigerant such as He or R32 is used.

As described above, the efficiency of the compressor can be improved by applying the permanent magnet type rotating electric machine according to any one of the first to fourth embodiments to the compressor.

It should be noted that the present invention is not limited to Examples 1 to 5 described above, and includes various modifications. The above-described Examples 1 to 5 have been described in detail in order to explain the present invention in an easy-to-understand manner, and in realizing the present invention, the present invention is not necessarily limited to those having all the described configurations. Moreover, it is possible to add, delete, or replace part of the configurations of the first to fifth embodiments with other configurations.

DESCRIPTION OF SYMBOLS 1... Permanent-magnet-type rotary electric machine 2... Stator 3... Rotor 4... Teeth 5... Core-back 6... Stator core 7... Slots 8a, 8b, 8c... Armature winding 11... Recess 12... Rotor core 13... Permanent magnet insertion portion 14 Permanent magnet 15 Shaft hole 16 Rivet insertion portion 17 Notch 60 Fixed scroll members 61, 64 End plates 62, 65 Spiral wrap 63 Orbiting scroll members 66a, 66b Compression chamber 67... Discharge port 68... Frame 69... Compression vessel 70... Discharge pipe 72... Crank shaft 73... Oil reservoir 74... Oil hole 75... Slide bearing

Claims (12)

Having a stator and a rotor rotatably arranged on the outer peripheral side of the stator,
The stator has a plurality of teeth radially provided radially outward from the center, and an armature winding wound around the plurality of teeth,
The rotor includes a plurality of permanent magnet insertion portions extending in a circumferential direction of the rotor and axially penetrating the rotor, and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portions. In a permanent magnet type rotating electric machine having
The rotor includes a plurality of rivet insertion portions formed through the rotor in the axial direction, and a plurality of cylindrical rivets inserted into the plurality of rivet insertion portions,
Assuming that the line connecting the rotation center of the rotor and the circumferential center of the permanent magnet is the d-axis, and the axis orthogonal to the d-axis at an electrical angle is the q-axis, the plurality of rivet insertion portions are the d A permanent magnet type electric rotating machine, wherein the rivet insertion portions are positioned on the axis, and the center lines of the plurality of rivet insertion portions are shifted from the d-axis toward the leading side with respect to the rotation direction of the rotor . Having a stator and a rotor rotatably arranged on the outer peripheral side of the stator,
The stator has a plurality of teeth radially provided radially outward from the center, and an armature winding wound around the plurality of teeth,
The rotor includes a plurality of permanent magnet insertion portions extending in a circumferential direction of the rotor and axially penetrating the rotor, and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portions. In a permanent magnet type rotating electric machine having
The rotor includes a plurality of rivet insertion portions formed through the rotor in the axial direction, and a plurality of cylindrical rivets inserted into the plurality of rivet insertion portions,
When a line connecting the rotation center of the rotor and the circumferential center of the permanent magnet is defined as a d-axis, and an axis orthogonal to the d-axis at an electrical angle is defined as a q-axis, the plurality of rivet insertion portions A position on the d-axis where the center lines of the plurality of rivet insertion portions are deviated from the d-axis toward the advancing side with respect to the rotation direction of the rotor, and the center lines of the plurality of rivet insertion portions A permanent magnet type electric rotating machine, wherein the permanent magnet rotating electric machine is arranged so as to be within a range of a position coinciding with a line connecting a rotation center of a rotor and a circumferential corner of the permanent magnet. In claim 1 or 2,
Between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor,
A permanent-magnet rotating electric machine, wherein a concave portion is formed radially outward from the inner peripheral surface of the rotor, and the concave portion is positioned on the q-axis. In claim 1 or 2,
Between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor,
A permanent magnet rotating electric machine, comprising a notch formed separately from the permanent magnet inserting portion, the notch being positioned on the q-axis. In claim 3,
The concave portion is composed of two linear portions respectively formed in the circumferential direction of the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor, and a curved portion formed between the two linear portions. A permanent magnet type rotary electric machine characterized by: In claim 5,
When the angle θp1 between the ends of the magnetic pole faces on the inner circumference side of the permanent magnet and the angle θp2 between the ends on the inner circumference side of the rotor of the two linear portions are set, θp2/θp1≦0.5. A permanent magnet type rotary electric machine characterized by having a relationship. In claim 5 or 6,
A permanent-magnet rotating electrical machine, wherein the recess has a gap between the two linear portions that widens from an outer peripheral side of the rotor toward an inner peripheral side of the rotor. In claim 1 or 2,
A permanent magnet rotating electric machine, wherein the permanent magnets inserted into the permanent magnet inserting portion are divided and embedded. A compressor comprising a compression mechanism for reducing the volume of gas, which is a working fluid, and a permanent magnet type rotating electric machine for driving the compression mechanism,
The permanent magnet type rotary electric machine,
Having a stator and a rotor rotatably arranged on the outer peripheral side of the stator,
The stator has a plurality of teeth radially provided radially outward from the center, and an armature winding wound around the plurality of teeth,
The rotor includes a plurality of permanent magnet insertion portions extending in a circumferential direction of the rotor and axially penetrating the rotor, and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portions. has
The rotor includes a plurality of rivet insertion portions formed through the rotor in the axial direction, and a plurality of cylindrical rivets inserted into the plurality of rivet insertion portions,
Assuming that the line connecting the rotation center of the rotor and the circumferential center of the permanent magnet is the d-axis, and the axis orthogonal to the d-axis at an electrical angle is the q-axis, the plurality of rivet insertion portions are the d A compressor, wherein the compressor is positioned on the axis, and the center lines of the plurality of rivet insertion portions are shifted from the d-axis toward the advance side with respect to the rotational direction of the rotor . A compressor comprising a compression mechanism for reducing the volume of gas, which is a working fluid, and a permanent magnet type rotating electric machine for driving the compression mechanism,
The permanent magnet type rotary electric machine,
Having a stator and a rotor rotatably arranged on the outer peripheral side of the stator,
The stator has a plurality of teeth radially provided radially outward from the center, and an armature winding wound around the plurality of teeth,
The rotor includes a plurality of permanent magnet insertion portions extending in a circumferential direction of the rotor and axially penetrating the rotor, and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portions. In a permanent magnet type rotating electric machine having
The rotor includes a plurality of rivet insertion portions formed through the rotor in the axial direction, and a plurality of cylindrical rivets inserted into the plurality of rivet insertion portions,
When a line connecting the rotation center of the rotor and the circumferential center of the permanent magnet is defined as a d-axis, and an axis orthogonal to the d-axis at an electrical angle is defined as a q-axis, the plurality of rivet insertion portions A position on the d-axis where the center lines of the plurality of rivet insertion portions are deviated from the d-axis toward the advancing side with respect to the rotation direction of the rotor, and the center lines of the plurality of rivet insertion portions A compressor, wherein the compressor is arranged so as to be within the range of a position coinciding with a line connecting the rotation center of the rotor and the circumferential corners of the permanent magnets. In claim 9 or 10 ,
Between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor,
A compressor according to claim 1, wherein a concave portion is formed radially outward from the inner peripheral surface of the rotor, and the concave portion is positioned on the q-axis. In claim 9 or 10 ,
Between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor,
A compressor comprising a notch formed separately from the permanent magnet inserting portion, wherein the notch is positioned on the q-axis.

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