JP2018207704A - Permanent magnet type rotary electric machine and compressor using the same - Google Patents

Abstract

To provide a permanent magnet type rotary electric machine which can be controlled at high performance even in a high speed area.SOLUTION: A rotator 3 arranged on an external peripheral side of a stator, comprises: a plurality of permanent magnet insertion parts 13 that are extended to a peripheral direction of the rotator 3, and run through it in an axial direction; and a plurality of plate-like permanent magnets 14 inserted into each of the permanent magnet insertion parts 13. In the rotator 3, a concave part 11 that is a space between the adjacent permanent magnet insertion parts 13 in the peripheral direction and is concaved toward a radial direction outer side from an inner peripheral surface of the rotator 3 is formed. When a connection wire connecting a rotational center of the rotator 3 with a peripheral direction central part of the permanent magnet 14 is a d-axis, and an axis orthogonal to the d-axis at an electric angle is a q-axis, the concave part 11 is positioned on the q-axis. In addition, a notch part 17 which is separated from the permanent magnet insertion parts 13 is provided in the space between the adjacent permanent magnet insertion parts 13 in the peripheral direction. The notch part 17 is positioned at the q-axis.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a permanent magnet type rotating electrical machine having a permanent magnet in a rotor and a compressor using the same.

  Permanent magnet rotating electrical machines are applied to various technical fields such as air conditioners, refrigerators, freezers, compressors in food showcases, and the like. Conventionally, in a permanent magnet type rotating electric machine, concentrated winding is adopted for the stator winding that is an armature winding, and a permanent magnet having a high magnetic flux density such as a neodymium magnet is adopted for the field magnet. Increased efficiency. However, along with the increase in output density due to miniaturization and higher efficiency, the influence of the non-linear magnetic characteristics (hysteresis) of the iron core becomes significant. Combined with the use of concentrated winding, the reluctance torque is reduced and the spatial harmonic magnetic flux component There is an increase in iron loss accompanying this increase.

  In order to solve this problem, a permanent magnet type rotating electrical machine having an abduction type rotor as described in Patent Document 1, for example, has been proposed. Patent Document 1 discloses a technique in which through holes that penetrate the rotor in the axial direction are provided on both side surfaces of a permanent magnet embedded in the rotor. In Patent Document 1, the reluctance torque is improved by forming an air layer having a high magnetic resistance in the through hole and extending the magnetic path by the magnetic flux flowing around the through hole.

JP 2009-136075 A

In the technique described in Patent Document 1, an air layer having high magnetic resistance is formed by through holes formed on both sides of a permanent magnet to reduce magnetic flux leakage. In Patent Document 1, a permanent magnet type rotating electric machine can obtain high efficiency in a medium / low speed range such as 1000-3000 min −1, but in a high speed range such as 7000-8000 min −1, the load torque is large or the electric motor When the number of armature windings is increased and the inductance becomes high, the influence of the magnetic flux (q-axis magnetic flux) due to the torque current is increased, so that the voltage / current phase advances and the power factor decreases. In particular, in Patent Document 1, the q axis that is electrically orthogonal to the magnetic flux axis d axis of the permanent magnet passes between the through holes, and the rotor core is located here. Magnetic flux leakage becomes significant, and the permanent magnet type rotating electrical machine has a problem that it cannot be controlled with high torque and high efficiency by a driving device such as an inverter.
Further, when the permanent magnet is embedded in the rotor, a permanent magnet insertion portion into which the permanent magnet is inserted is formed in the rotor. Since this permanent magnet insertion part inserts a permanent magnet, an opening slightly larger than the permanent magnet to be inserted is formed. The permanent magnet inserted from the permanent magnet insertion portion and embedded in the rotor receives a circumferential force due to acceleration / deceleration accompanying the rotation of the rotor, and tries to move in the embedded space. As described in Patent Document 1, in the technique in which through holes are formed on both sides of the permanent magnet, it is necessary to provide a protrusion or the like in the space where the permanent magnet is embedded in order to prevent the permanent magnet from moving in the circumferential direction. There is. However, in the technique described in Patent Document 1, since the load of the permanent magnet needs to be received by the protrusion or the like, the protrusion or the magnet may be damaged due to repeated collision between the protrusion and the permanent magnet.

  SUMMARY OF THE INVENTION 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 region and a compressor using the same.

  In addition to the above, an object of the present invention is to provide a permanent magnet type rotating electrical machine capable of preventing breakage of a magnet due to acceleration / deceleration accompanying rotation of a rotor, and a compressor using the same.

  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, the stator being radially outward from the center. A plurality of teeth provided radially and armature windings wound around the plurality of teeth, the rotor extending in a circumferential direction of the rotor and penetrating in an axial direction In the permanent magnet type rotating electrical machine having a plurality of permanent magnet insertion portions formed as described above and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portion, the rotor has a periphery of the rotor. Between the permanent magnet insertion portions adjacent to each other in a direction, forming a recess recessed radially outward from the inner peripheral surface of the rotor, and the rotational center of the rotor and the circumferential direction of the permanent magnet A line connecting the central portion is defined as a d-axis, and an axis orthogonal to the d-axis by an electrical angle is defined as a q-axis. Come is to the recesses are positioned on the q-axis.

  Further, the present invention is characterized by having a stator and a rotor rotatably disposed on the outer peripheral side of the stator, and the stator is provided radially from the center toward the radially outer side. A plurality of teeth and an armature winding wound around the plurality of teeth, and the rotor is formed to extend in the circumferential direction of the rotor and penetrate in the axial direction. In a permanent magnet type rotating electrical machine having a plurality of permanent magnet insertion portions and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portions, the rotor is adjacent to the rotor in the circumferential direction. A line is provided between the permanent magnet insertion portions, the cutout portion being formed so as to be isolated from the permanent magnet insertion portion, and a line connecting the rotation center of the rotor and the circumferential central portion of the permanent magnet being d The notch is the q axis when the axis perpendicular to the d axis and the electrical angle is the q axis. In that is located in.

  In addition, a feature of the present invention is that the compressor includes a compression mechanism that reduces the volume of the gas that is the working fluid, and a permanent magnet type rotating electrical machine that drives the compression mechanism. A stator and a rotor rotatably arranged on the outer peripheral side of the stator, and the stator includes a plurality of teeth provided radially from the center toward the radially outer side, and the plurality of teeth. An armature winding wound around a tooth, and the rotor has a plurality of permanent magnet insertion portions formed extending in the circumferential direction of the rotor and penetrating in the axial direction; A plurality of plate-like permanent magnets to be inserted into the magnet insertion portion, and the rotor includes a space between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor. During the rotation of the rotor, a recess that is recessed radially outward from the inner peripheral surface is formed. The line connecting the circumferential direction central portion of the permanent magnet and the d-axis, and an axis orthogonal with the d-axis and the electrical angle and the q-axis is to the recesses are positioned on the q-axis.

  Furthermore, a feature of the present invention is that the compressor includes a compression mechanism that reduces the volume of the gas that is the working fluid, and a permanent magnet type rotating electrical machine that drives the compression mechanism. A stator and a rotor rotatably arranged on the outer peripheral side of the stator, and the stator includes a plurality of teeth provided radially from the center toward the radially outer side, and the plurality of teeth. An armature winding wound around a tooth, and the rotor has a plurality of permanent magnet insertion portions formed extending in the circumferential direction of the rotor and penetrating in the axial direction; A plurality of plate-like permanent magnets to be inserted into the magnet insertion portion, and the rotor is between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor, and the permanent magnet insertion A notch portion formed separately from the portion, and the rotation center of the rotor and the front The line connecting the circumferential direction central portion of the permanent magnet and the d-axis, and an axis orthogonal with the d-axis and the electrical angle and the q-axis is to the cutout portion was positioned on the q-axis.

  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 area 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 electrical machine capable of preventing breakage of a magnet due to acceleration / deceleration accompanying rotation of a rotor, and a compressor using the same.

  Problems, configurations, and effects other than those described above will become apparent from the following description of embodiments.

It is sectional drawing of the permanent magnet type rotary electric machine which concerns on Example 1 of this invention. It is sectional drawing which shows the rotor core shape of the permanent magnet type rotary electric machine which concerns on Example 1 of this invention. It is a vector diagram at the time of low speed and low load torque of the permanent magnet type rotating electrical machine of the comparative example. It is a vector diagram at the time of high speed and high load torque of the permanent magnet type rotating electrical machine of the comparative example. It is a vector diagram at the time of high speed and high load torque of the permanent magnet type rotating electrical machine according to the first embodiment of the present invention. The torque characteristic (solid line) of the permanent magnet type rotary electric machine which concerns on Example 1 of this invention is shown. It is sectional drawing which shows the rotor core shape of the permanent magnet type rotary electric machine which concerns on Example 2 of this invention. It is sectional drawing of the compressor which is based on Example 3 of this invention.

  Embodiments of the present invention will be described below with reference to FIGS. In each figure, the same reference numerals indicate the same constituent elements or constituent elements having similar functions. Further, the permanent magnet type rotating 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 rotor poles, the number of stator slots, and the ratio thereof are not limited to the values in each embodiment, and other values can provide the same effects as those in each embodiment. For example, the number of poles of the rotor may be 4 poles, 8 poles, 10 poles, 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 a permanent magnet is embedded in a rotor core.

  In the following description, “axial direction” indicates the rotational axis direction of the rotor, “radial direction” indicates the radial direction of the rotor, and “circumferential direction” indicates the circumferential direction of the rotor.

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

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

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

  In the permanent magnet type rotating electrical machine 1 of the first embodiment, when a three-phase alternating current is passed through the armature winding 8 composed of the three-phase windings 8a to 8c, a rotating magnetic field is generated. The rotor 3 is rotated by the electromagnetic force acting on the permanent magnet 14 and the rotor core 12 by the 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 electrical machine 1 is operated, the stator core 6 and the rotor core 12 are made of silicon steel plates. It is preferable to comprise a laminated body in which a plurality of thin plates made of magnetic steel plates are laminated.

  FIG. 2 is a cross-sectional view showing the rotor core shape of the permanent magnet type rotating electrical machine 1 according to the first embodiment. In FIG. 2, the rotor 3 is configured by laminating a rotor core 12. In the vicinity of the inner peripheral surface of the rotor core 12, there are a plurality of permanent magnet insertion portions 13 that extend in the circumferential direction of the rotor 3 and penetrate in the axial direction (a rectangular shape with a long cross section). In the first embodiment, the number is 6).

  Flat permanent magnets 14 made of a magnet material, for example, rare earth neodymium, are inserted into the plurality of permanent magnet insertion portions 13. The permanent magnet insertion portion 13 is formed slightly larger than the permanent magnet 14, and the outer periphery of the permanent magnet 14 is covered with the rotor core 12. The permanent magnet 14 moves through the gap of the permanent magnet insertion portion 13 due to acceleration / deceleration accompanying the rotation of the rotor 3. However, since the periphery is covered with the rotor core 12, the load acting on the permanent magnet 14 is permanent. It is received by the surface of the rotor core 12 in the magnet insertion part 13. For this reason, there is no possibility of cracks or the like in the rotor core 12 itself. Moreover, since the permanent magnet 14 also contacts the surface of the rotor core 12 in the permanent magnet insertion portion 13, there is no possibility that the permanent magnet 14 is 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 magnet 14, that is, the virtual axis connecting the longitudinal center (cross section center) of the permanent magnet 14 and the rotation center O is the d axis (magnetic flux). Axis), and an axis that is electrically perpendicular to the d-axis, that is, an electrical angle (axis between permanent magnets), is defined as a 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 perpendicular to the d-axis geometrically.

  The rotor core 12 of the rotor 3 is recessed outwardly in the radial direction from the inner peripheral surface of the rotor on the q axis between adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnet 14). A recess 11 is provided. The recess 11 is located on the q axis and suppresses the q axis magnetic flux as will be described later. Further, the rotor 3, that is, the rotor core 12 is positioned on the inner peripheral side with respect to the recess 11, and the inner peripheral portion where the gap length (gap) between the stator 2 and the teeth 4 is the shortest g 1, and the gap And an inner peripheral portion whose length is g2 longer than g1.

  Next, the configuration of the recess 11 will be described. The recess 11 has two straight portions 11b and 11c that are parallel to the circumferential length direction of the permanent magnet 14, and a curved portion 11a that connects the end portions of the two straight portions 11b and 11c on the rotor inner peripheral side. ing. Thus, by providing the curved part 11a in the recessed part 11, the influence of the stress accompanying a rotor centrifugal force can be relieved in a high speed region. 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, stress concentration associated with the rotor centrifugal force in the recess 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 end portions of the inner peripheral side magnetic pole surface of the permanent magnet 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 end portions (curve portion 11a) on the outer periphery side of the rotor is θp2, θp1 and θp2 are set so as to satisfy the relationship θp2 / θp1 ≦ 0.5.

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

  Further, according to the examination of the present invention, in the case of the rotor provided with the concave portion 11 having the curved portion as in the present embodiment, by setting 0.18 ≦ θp2 / θp1, as shown in FIG. Thus, a substantial torque improvement effect in the high speed range can be obtained by suppressing the q-axis magnetic flux.

  The rotor core 12 of the rotor 3 of the first embodiment is recessed from the inner peripheral surface of the rotor toward the radially outer side between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnet 14). A recess 11 is provided. And the recessed part 11 is located on the q-axis. Since the air layer is formed by the recess 11 and the magnetic resistance is increased by the air layer, it is difficult for the magnetic flux to pass between the permanent magnet insertion portions 13 (permanent magnets 14) adjacent in the circumferential direction. For this reason, the leakage magnetic flux from between the permanent magnets 14 can be reduced, the influence of the q-axis magnetic flux can be suppressed, and the harmonic magnetic flux generated by the interaction between the induced electromotive force and the armature current can be reduced. That is, the recess 11 suppresses the armature reaction and reduces the harmonic component of the in-machine magnetic flux.

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

  An air layer is formed by the notches 17 and the magnetic resistance is increased by the air layer. Therefore, it is difficult for magnetic flux to pass between the permanent magnet insertion portions 13 (permanent magnets 14) adjacent in the circumferential direction. And the notch part 17 is located on the q-axis. For this reason, the leakage magnetic flux from between the permanent magnets 14 can be reduced, the influence of the q-axis magnetic flux can be suppressed, and the harmonic magnetic flux generated by the interaction between the induced electromotive force and the armature current can be reduced. That is, the notch portion 17 suppresses the armature reaction and reduces the harmonic component of the in-machine magnetic flux. Further, since the outer periphery of the permanent magnet 14 embedded in the permanent magnet insertion portion 13 is covered with the rotor core 12, the permanent magnet 14 passes through the gap of the permanent magnet insertion portion 13 due to acceleration / deceleration accompanying the rotation of the rotor 3. Even if it moves, there is no fear of cracks or the like in the rotor core 12 itself, and neither the permanent magnet 14 nor the permanent magnet 14 is damaged.

  3a and 3b are vector diagrams of a permanent magnet type rotating electrical machine which is a comparative example according to the conventional invention. Note that FIG. 3A shows a low speed / low load torque, and FIG. 3B shows a high speed / high load torque. The vector diagrams of FIGS. 3a and 3b use the dq axis coordinate system for controlling the permanent magnet type rotating electrical machine, and the d axis direction of this coordinate system is the d axis direction of the rotor (see FIG. 2). ).

  3A and 3B, Φm represents a magnetic flux in the d-axis direction of the rotor by the permanent magnet 14. In the present coordinate system, 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. 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 by the permanent magnet and the magnetic flux (Φd, Φq) by the armature current I1. Em represents an induced voltage at no load. V1 indicates the terminal voltage of the stator winding, and the phase difference is 90 ° with respect to the main magnetic flux Φ1. V1 is represented by a combined vector of the induced voltage Em and a voltage drop (ωΦd, ωΦq: ω is an 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 the time of low speed and low load torque, since the armature current I1 and its q-axis component are small and the q-axis magnetic flux is small, the phase difference between the main magnetic flux Φ1 and the magnetic flux Φm of the permanent magnet is small. For this reason, even in the method of Patent Document 1, the power factor becomes relatively high, and a 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. For this reason, although a power factor falls and the armature current I1 is increased, a torque does not become large and efficiency falls.

  FIG. 4 is a vector diagram of the permanent magnet type rotating electric machine according to the first embodiment. FIG. 4 shows the vectors of the permanent magnet type rotating electrical machine of the first embodiment when the high speed and high load torque are applied, and the vectors (Φ1 ′, I1 ′, V1 ′) shown by broken lines. In order to facilitate understanding of the effect of the first embodiment, the vector diagram of the comparative example shown in FIG.

  As shown in FIG. 4, in this embodiment, when the rotor 3 is provided with the recess 11 and the notch 17 to increase the magnetic resistance in the q-axis direction of the rotor, the armature current I1 is increased. The influence of the q-axis magnetic flux Φq can be suppressed. For this reason, even at the time of high speed and high load torque, a decrease in the power factor is suppressed, and a desired torque can be obtained while maintaining a relatively high efficiency.

  Here, the configuration of the recess 11 and the cutout 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 more specifically.

  As shown in FIG. 2, the gap length g <b> 2 between the radially inner 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 larger than g1. That is, in the inner periphery of the rotor 3, the recess 11 has a portion where the gap length with the teeth 4 of the stator 2 is the shortest g1 and a portion where the gap length is longer than g1 and g2. . Further, as shown in FIG. 2, the recess 11 includes two straight portions (11 b and 11 c) parallel to the circumferential length direction of the permanent magnet 14, and end portions on the rotor inner peripheral side of these straight portions. And a curved portion (11a) connecting the two. In this way, the inner periphery of the rotor 3 is configured.

  Furthermore, in the recessed part 11, the curved part 11a of the inner peripheral side located so that it may follow a rotation direction between the adjacent permanent magnets 14, and the rotation direction side from the edge part of the rotation direction of the curved part 11a of the inner peripheral side A linear portion 11b on the substantially linear rotational direction side that extends so as to extend in the direction opposite to the end portion on the anti-rotational direction side of the curved portion 11a on the inner peripheral side, and a substantially linear anti-linear portion located so as to spread in the counter rotational direction side. The straight portion 11c on the rotation direction side is connected. That is, the distance between the central portion of the curved portion 11 a of the recess 11 and the rotation center O is longer than the distance between the permanent magnet 14 and the rotation center O. Thereby, q-axis magnetic flux is reduced. Although the clockwise direction is described here as the rotation direction, the rotor 3 may rotate counterclockwise. By such a recess 11 and the notch 17 described above, the magnetic flux of the permanent magnet 14 can be collected in the vicinity of the d-axis.

  In the present embodiment, the concave portion 11 is a curve connecting two linear portions (11b, 11c) parallel to the circumferential length direction of the permanent magnet 14 and the end portion of each linear portion on the rotor inner peripheral side. Although it is comprised by a part, it is not limited to this, What is necessary is just the shape which spreads right and left as it goes to the outer peripheral side from the inner peripheral side of the recessed part 11.

  As described above, the angle θp1 between the end portions of the inner peripheral side magnetic pole surface of the permanent magnet 14 constituting one magnetic pole of the rotor 3, and the two linear portions 11b and 11c of the recess 11 on the inner peripheral side of the rotor. The angle θp2 between the end portions is set to satisfy 0.18 ≦ θp2 / θp1 ≦ 0.5, and the rotor 3 is penetrated in the axial direction on the side surface of the permanent magnet insertion portion 13 (permanent magnet 14). It is possible to increase the q-axis magnetic resistance by forming the notch 17 to be formed. 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 magnetic flux Φm of the permanent magnet are reduced. Thereby, a high torque is obtained in a high speed region. Further, when the inductance of the permanent magnet type rotating electrical machine is large, it is possible to suppress a power factor decrease due to the influence of the armature reaction. As a result, it is possible to reduce the size and increase the efficiency of the permanent magnet type rotating electrical machine while suppressing a decrease in torque.

  FIG. 5 shows the torque characteristics (solid line) of the permanent magnet type rotating electrical machine of the first embodiment. The vertical axis and the horizontal axis are torque and armature current, respectively. However, the rated current is 1P. U. In addition, the torque (high-speed torque) of Example 1 when the rated current is passed is 1 P.V. U. It is said. As a comparative example, the torque characteristics of a permanent magnet type rotating electrical machine according to the conventional invention are indicated by broken lines. As shown in FIG. 5, the torque of the permanent magnet type rotating electric machine of the first embodiment is larger than that of the comparative example according to the conventional invention, and is particularly large in the high speed range.

  According to the first embodiment, a recess 11 that is recessed radially outward from the inner peripheral surface of the rotor 3 is provided between adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnet 14). Since the recess 11 is positioned on the q-axis, the power factor decrease due to the influence of the armature reaction is suppressed, and the torque decrease in the high speed range can be suppressed. For this reason, the permanent magnet type rotating electrical machine can be made highly efficient and downsized.

  In addition, according to the first embodiment, a notch portion 17 is provided between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnet 14), and is formed so as to be isolated from the permanent magnet insertion portion 13. Since the notch 17 is positioned on the q-axis, the power factor decrease due to the influence of the armature reaction is suppressed, and the torque decrease in the high speed region can be suppressed. For this reason, the permanent magnet type rotating electrical machine can be made highly efficient and downsized.

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

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

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

  In the second embodiment, unlike the first embodiment (FIG. 2), two permanent magnets are provided for each magnetic pole of the rotor 3. When a permanent magnet is used as in the first embodiment, heat loss due to eddy current becomes a problem. In particular, when performing high rotation, the frequency and fluctuation range of the fluctuating magnetic field applied to the magnet increase, and the heat loss increases accordingly. In order to reduce the heat loss due to this eddy current, the permanent magnet 14 embedded in the permanent magnet insertion portion 13 is divided and arranged in this embodiment (14a, 14b). In the divided permanent magnets 14a and 14b, the magnetic flux linked to the individual magnets is reduced. Therefore, the eddy current density of each of the divided permanent magnets 14a and 14b is reduced, and the eddy current loss as a total amount 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, loss due to eddy current can be reduced.

  In addition, according to the second embodiment, the concave portion 11 is provided between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnet 14). Since the recess 11 is positioned on the q-axis, the power factor decrease due to the influence of the armature reaction is suppressed, and the torque decrease in the high speed range can be suppressed.

  Furthermore, according to the second embodiment, a notch portion 17 is provided between the adjacent permanent magnet insertion portions 13 (between the poles of the permanent magnet 14), and is formed so as to be isolated from the permanent magnet insertion portion 13. Since the notch 17 is positioned on the q-axis, the power factor decrease due to the influence of the armature reaction is suppressed, and the torque decrease in the high speed range can be suppressed. For this reason, the permanent magnet type rotating electrical machine can be made highly efficient and downsized.

  Even in the rotor structure in which the permanent magnets 14 are divided and arranged as described above, it is possible to improve the power factor reduction due to the influence of the armature reaction, suppress the torque reduction, and reduce the size and increase the efficiency. Absent.

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

  Next, an example in which the permanent magnet type rotating electrical machines of the first and second embodiments are applied to a scroll compressor will be described with reference to FIG. FIG. 7 is a cross-sectional view of a compressor according to Embodiment 3 of the present invention.

  In FIG. 7, 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 mesh with each other in the cylindrical compression container 69. A compression mechanism is provided, and the orbiting scroll member 63 orbits through the crankshaft 72 by a permanent magnet type rotating electrical machine to perform the compression operation. Example 1 or Example 2 of the present invention is applied as this permanent magnet type rotating electrical machine.

  Of the compression chambers 66 a to 66 b formed by the fixed scroll member 60 and the orbiting scroll member 63, the compression chamber located on the outermost side is the fixed scroll member 60 and the orbiting scroll member 63 along with the orbiting motion. The volume gradually decreases. When the compression chambers 66 a and 66 b reach the vicinity of the center of the fixed scroll member 60 and the orbiting scroll member 63, the compressed gas that is the working fluid in both the compression chambers is discharged from the 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 and reaches the compression container 69 below the frame 68, and is provided on the side wall of the compression container 69. From the compressor.

  Moreover, the permanent magnet type rotating electrical machine that drives the compressor is controlled by a separate inverter (not shown) and rotates at a rotation speed suitable for the compression operation. Here, the permanent magnet type rotating electrical machine includes the stator 2 and the rotor 3, and the crankshaft 72 is attached to the shaft hole 15 in the first and second embodiments. When the crankshaft 72 is rotated by the permanent magnet type rotating electrical machine, the orbiting scroll member 63 does not rotate, but performs orbiting and revolving motion having a predetermined eccentric amount at the upper portion of the crankshaft 72 as a radius. An oil hole 74 is provided in the crankshaft 72, and as the crankshaft 72 rotates, the lubricating oil in the oil reservoir 73 at the lower part of the compression container 69 is supplied to the slide bearing 75 through the oil hole 74. The By applying the permanent magnet type rotating electric machine according to any one of the first and second embodiments described above to such a compressor, the efficiency of the compressor can be improved and energy saving can be achieved.

  By the way, in many current home and commercial air conditioners, the R410A refrigerant is sealed in the compression container 69, and the ambient temperature of the permanent magnet type rotating electric machine is often 80 ° C. or more. In the future, the ambient temperature of the permanent magnet type rotating electrical machine further rises as the adoption of R32 refrigerant having a smaller global warming potential progresses. The permanent magnet 14, particularly a neodymium magnet, has a residual magnetic flux density that decreases at a high temperature, and an armature current increases to ensure the same output. Therefore, the permanent magnet type rotating electric machine according to the first or second embodiment described above. By applying, efficiency reduction can be suppressed. In the third embodiment, the example in which the permanent magnet type rotating electric machine of the first embodiment or the second embodiment described above is applied to the scroll compressor has been described. However, in providing the third embodiment, the type of refrigerant is limited. It is not a thing. Further, as the type of the compressor, the example of the scroll compressor has been described in the third embodiment, but the present invention can also be applied to a compressor having other compression mechanisms such as a rotary compressor and a reciprocating compressor. .

  According to the third embodiment, a compressor capable of saving energy can be realized by applying a small and highly efficient permanent magnet type rotating electrical machine. In addition, by applying the permanent magnet type rotating electric machine according to the first and second embodiments, the operating range can be expanded such that the compressor can be operated at high speed.

  Furthermore, in refrigerants such as He and R32, leakage from gaps in the compressor is larger than refrigerants such as R22, R407C, and R410A, and the ratio of leakage to the circulation rate is large particularly during low-speed operation. Decreases. In order to improve the efficiency at the time of low circulation (low speed operation), it is effective to reduce the leakage loss by downsizing the compression mechanism and increasing the rotational speed to obtain the same circulation. Furthermore, it is preferable to increase the maximum rotational speed in order to ensure the maximum circulation amount. On the other hand, by applying the permanent magnet type rotating electrical machine 1 of the first and second embodiments described above to the compressor, it is possible to increase the maximum torque and the maximum number of rotations, and to reduce the loss in the high speed range. Therefore, 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 of the first embodiment or the second embodiment to the compressor.

  In addition, this invention is not limited to Example 1-3 mentioned above, Various modifications are included. The above-described first to third embodiments are described in detail for easy understanding of the present invention, and the present invention is not necessarily limited to those having all the configurations described above. Moreover, it is possible to add / delete / replace other configurations for a part of the configurations of the first to third embodiments.

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 17 Notch portion 60 Fixed scroll members 61 and 64 End plates 62 and 65 Spiral wrap 63 Orbiting scroll members 66a and 66b Compression chamber 67 Discharge port 68 ... Frame 69 ... Compression container 70 ... Discharge pipe 72 ... Crankshaft 73 ... Oil reservoir 74 ... Oil hole 75 ... Sliding bearing

Claims (10)

A stator, and a rotor rotatably arranged on the outer peripheral side of the stator,
The stator includes a plurality of teeth provided radially from the center radially outward, and armature windings wound around the plurality of teeth.
The rotor includes a plurality of permanent magnet insertion portions formed extending in the circumferential direction of the rotor and penetrating in the axial direction, and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portion. In the permanent magnet type rotating electrical machine having
The rotor is formed between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor, and a concave portion that is recessed radially outward from the inner circumferential surface of the rotor,
When the line connecting the rotation center of the rotor and the central portion in the circumferential direction of the permanent magnet is the d-axis, and the axis orthogonal to the d-axis in terms of electrical angle is the q-axis, the recess is positioned on the q-axis. A permanent magnet type rotating electrical machine characterized by being made. In claim 1,
The rotor includes a notch portion formed between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor and separated from the permanent magnet insertion portion. A permanent magnet type rotating electrical machine characterized by being positioned on the q-axis. In claim 1 or 2,
The concave portion is composed of two linear portions formed in the circumferential direction of the permanent magnet insertion portion adjacent to the circumferential direction of the rotor, and a curved portion formed between the two linear portions. Permanent magnet type rotating electrical machine characterized by In claim 3,
When the angle θp1 between the ends of the magnetic pole surface on the inner peripheral side of the permanent magnet and the angle θp2 between the ends on the inner peripheral side of the two linear portions are set, θp2 / θp1 ≦ 0.5. A permanent magnet type rotating electrical machine characterized by having a relationship. In claim 3 or 4,
The permanent magnet-type rotating electrical machine, wherein the recess has an interval between the two linear portions that extends from the outer peripheral side of the rotor toward the inner peripheral side of the rotor. A stator, and a rotor rotatably arranged on the outer peripheral side of the stator,
The stator includes a plurality of teeth provided radially from the center radially outward, and armature windings wound around the plurality of teeth.
The rotor includes a plurality of permanent magnet insertion portions formed extending in the circumferential direction of the rotor and penetrating in the axial direction, and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portion. In the permanent magnet type rotating electrical machine having
The rotor includes a notch portion formed between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor and separated from the permanent magnet insertion portion,
When a line connecting the rotation center of the rotor and the central portion in the circumferential direction of the permanent magnet is a d-axis, and an axis orthogonal to the d-axis in terms of electrical angle is a q-axis, the notch is on the q-axis. A permanent magnet type rotating electrical machine characterized by being positioned. In any one of Claims 1 thru | or 6,
The permanent magnet type rotating electrical machine, wherein the permanent magnet inserted into the permanent magnet insertion portion is embedded in a divided manner. In a compressor comprising a compression mechanism that reduces the volume of gas that is a working fluid, and a permanent magnet type rotating electrical machine that drives the compression mechanism,
The permanent magnet type rotating electrical machine is:
A stator, and a rotor rotatably arranged on the outer peripheral side of the stator,
The stator includes a plurality of teeth provided radially from the center radially outward, and armature windings wound around the plurality of teeth.
The rotor includes a plurality of permanent magnet insertion portions formed extending in the circumferential direction of the rotor and penetrating in the axial direction, and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portion. Have
The rotor is formed between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor, and a concave portion that is recessed radially outward from the inner circumferential surface of the rotor,
When the line connecting the rotation center of the rotor and the central portion in the circumferential direction of the permanent magnet is the d-axis, and the axis orthogonal to the d-axis in terms of electrical angle is the q-axis, the recess is positioned on the q-axis. A compressor characterized by having been made. In claim 8,
The rotor includes a notch portion formed between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor and separated from the permanent magnet insertion portion. A compressor characterized by being positioned on the q-axis. In a compressor comprising a compression mechanism that reduces the volume of gas that is a working fluid, and a permanent magnet type rotating electrical machine that drives the compression mechanism,
The permanent magnet type rotating electrical machine is:
A stator, and a rotor rotatably arranged on the outer peripheral side of the stator,
The stator includes a plurality of teeth provided radially from the center radially outward, and armature windings wound around the plurality of teeth.
The rotor includes a plurality of permanent magnet insertion portions formed extending in the circumferential direction of the rotor and penetrating in the axial direction, and a plurality of plate-like permanent magnets inserted into the permanent magnet insertion portion. Have
The rotor includes a notch portion formed between the permanent magnet insertion portions adjacent to each other in the circumferential direction of the rotor and separated from the permanent magnet insertion portion,
When a line connecting the rotation center of the rotor and the central portion in the circumferential direction of the permanent magnet is a d-axis, and an axis orthogonal to the d-axis in terms of electrical angle is a q-axis, the notch is on the q-axis. A compressor characterized by being positioned.

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