JP5202492B2 - Rotor, blower and compressor of embedded permanent magnet motor - Google Patents

Description

  The present invention relates to a rotor of a permanent magnet embedded motor, and more particularly to a slit shape disposed in an outer peripheral core portion of a permanent magnet insertion hole. The present invention also relates to a blower and a compressor that use the rotor of the permanent magnet embedded motor for the permanent magnet embedded motor. Hereinafter, the permanent magnet embedded motor may be simply referred to as an electric motor.

  Conventionally, there has been proposed a technique for reducing torque ripple of an electric motor by dividing a rotor into a plurality of rotor cores and providing a skew by shifting a predetermined angle in the axial direction.

  However, the technology for reducing the torque ripple of these electric motors has a problem that harmonic components of vibrations of a plurality of orders cannot be reduced at the same time because there is only one axial deviation angle formed from each of the rotor cores. .

  Therefore, the following rotors have been proposed for the purpose of supplying a rotor that can simultaneously reduce the harmonic components of a plurality of orders of vibration. That is, a plurality of rotor portions (1a, 1b, 1c, 1d) are connected to each other in the axial direction without rotating in the circumferential direction about the axis (Z), and each of the plurality of rotor portions is provided. Is configured uniformly in the axial direction, and each of the plurality of rotor parts forms a side surface parallel to the axis and a plurality of different magnetic pole surfaces on the side surface with a predetermined number of pairs (p). (6), and the predetermined number of pairs is the same in each of the plurality of rotor portions, and among the plurality of rotor portions, the first rotor portion (1b) and the second rotor portion ( 1a) forms a first skew angle (θ1, φ1) in the circumferential direction, and among the plurality of rotor portions, the first rotor portion and the third rotor portion (1c) are in the circumferential direction. A second skew angle (θ2, φ3) is formed, and the first skew angle is larger than 1. The value obtained by dividing 180 degrees by the product of the first integer and the number of pairs, and the second skew angle is 180 degrees as a product of the second integer and the number of pairs that are larger than 1 and different from the first integer. Is a value obtained by dividing the axis and rotates about the axis (see, for example, Patent Document 1).

JP 2008-131783 A

  The rotor of a conventional permanent magnet embedded motor has been designed to reduce noise by providing a slit or skew to reduce torque ripple. However, applying the skew has a problem in that since the phase of the rotor is changed and the manufacturing is difficult, the manufacturing cost increases, and the efficiency decreases due to a decrease in torque.

  The present invention has been made to solve the above-described problems, and provides a rotor of a permanent magnet embedded motor in which torque ripple can be reduced by a slit without applying a skew.

  Moreover, the air blower and compressor which use the rotor of the permanent magnet embedded motor for a permanent magnet embedded motor are provided.

The rotor of the permanent magnet embedded motor according to the present invention includes a rotor core formed by laminating a predetermined number of electromagnetic steel sheets punched into a predetermined shape,
A plurality of permanent magnet insertion holes formed along the outer periphery of the rotor core;
Permanent magnet end gaps provided at both ends of the permanent magnet insertion hole;
A permanent magnet inserted into the permanent magnet insertion hole;
A plurality of slits formed in the iron core portion outside the permanent magnet insertion hole,
The plurality of slits are formed substantially in parallel and are inclined at a predetermined angle with respect to the magnetic pole center line,
In adjacent magnetic poles, a plurality of slits of one magnetic pole are formed to be inclined at a predetermined angle in the rotation direction with respect to the magnetic pole center line, and a plurality of slits of the other magnetic pole are counter-rotated with respect to the magnetic pole center line. It is formed to be inclined at a predetermined angle in the direction.

  The rotor of the embedded permanent magnet motor according to the present invention is provided in adjacent magnetic poles, and the plurality of slits of one magnetic pole are formed to be inclined at a predetermined angle in the rotation direction with respect to the magnetic pole center line. Since the plurality of slits of the magnetic pole are formed to be inclined at a predetermined angle in the counter-rotating direction with respect to the magnetic pole center line, torque ripple can be reduced by the effect of shifting the torque phase of the adjacent magnetic poles.

It is a figure shown for a comparison and is a cross-sectional view of a rotor 300 of a general permanent magnet embedded motor. The elements on larger scale of FIG. FIG. 2 is a cross-sectional view of the rotor core 301 of FIG. 1. The elements on larger scale of FIG. FIG. 5 is a cross-sectional view of a rotor 400 of a general permanent magnet embedded motor in which a slit 405 is inclined in the rotation direction, and is shown for comparison. The elements on larger scale of FIG. FIG. 6 is a cross-sectional view of the rotor core 401 in FIG. 5. The elements on larger scale of FIG. FIG. 5 is a cross-sectional view of a rotor 500 of a general embedded permanent magnet motor in which a slit 505 is inclined in the counter-rotating direction, and is shown for comparison. The elements on larger scale of FIG. FIG. 10 is a cross-sectional view of the rotor core 501 in FIG. 9. The elements on larger scale of FIG. The figure which compared the torque of the rotor 300,400,500. FIG. 3 shows the first embodiment, and is a cross-sectional view of a rotor 100 of a permanent magnet embedded motor. The A section enlarged view of FIG. The B section enlarged view of FIG. The C section enlarged view of FIG. The D section enlarged view of FIG. FIG. 15 is a cross-sectional view of the rotor core 101 of FIG. 14. The A section enlarged view of FIG. The B section enlarged view of FIG. The C section enlarged view of FIG. The D section enlarged view of FIG. FIG. 5 shows the first embodiment and is a diagram comparing torques of rotors 100, 400, and 500. FIG. FIG. 5 shows the first embodiment, and is a cross-sectional view of a rotor 200 of a permanent magnet embedded motor according to a modification. The A section enlarged view of FIG. The B section enlarged view of FIG. The C section enlarged view of FIG. The D section enlarged view of FIG. FIG. 26 is a cross-sectional view of the rotor core 201 of FIG. 25. The A section enlarged view of FIG. The B section enlarged view of FIG. The C section enlarged view of FIG. The D section enlarged view of FIG.

Embodiment 1 FIG.
FIGS. 1 to 13 are diagrams for comparison, and are cross-sectional views of a rotor 300 of a general permanent magnet embedded motor, FIG. 2 is a partially enlarged view of FIG. 1, and FIG. 3 is a rotor of FIG. 4 is a partially enlarged view of FIG. 3, FIG. 5 is a cross-sectional view of a rotor 400 of a general permanent magnet embedded motor in which a slit 405 is inclined in the rotation direction, and FIG. 5 is a partially enlarged view of FIG. 5, FIG. 7 is a transverse sectional view of the rotor core 401 of FIG. 5, FIG. 8 is a partially enlarged view of FIG. 7, and FIG. 9 is a general permanent magnet in which the slit 505 is inclined in the counter-rotating direction. FIG. 10 is a partially enlarged view of FIG. 9, FIG. 11 is a transverse sectional view of the rotor core 501 in FIG. 9, FIG. 12 is a partially enlarged view of FIG. These are the figures which compared the torque of the rotor 300,400,500.

  First, a rotor of a general permanent magnet embedded motor will be described. The rotor 300 of the embedded permanent magnet motor shown in FIGS. 1 to 4 includes at least a rotor core 301 and a permanent magnet 303.

  Note that the rotor 300 of the permanent magnet embedded motor is simply referred to as the rotor 300. Further, the rotor 300 or the like may be simply referred to as a rotor.

  The rotor core 301 has a substantially circular cross-sectional shape as a whole, a thin electromagnetic steel plate (for example, a thickness of about 0.1 to 1.0 mm, and a non-oriented electrical steel plate (biased in a specific direction of the steel plate). The crystal axis direction of each crystal is arranged as randomly as possible so as not to exhibit magnetic properties))) is punched with a mold into a predetermined shape, and a predetermined number (multiple) is laminated.

  The rotor core 301 is formed with four permanent magnet insertion holes 302 having a rectangular cross section so as to form a quadrangle in the circumferential direction (see FIG. 3).

  A four-pole rotor 300 is formed by inserting four flat-plate-shaped permanent magnets 303 magnetized so that N poles and S poles are alternately arranged inside the permanent magnet insertion hole 302. .

  The permanent magnet 303 is made of rare earth mainly composed of neodymium, iron, or boron.

  At both ends of the permanent magnet insertion hole 302, permanent magnet end gaps 304 that are connected to the permanent magnet insertion hole 302 are formed.

  A plurality of slits 305 are formed in the peripheral direction of the permanent magnet insertion hole 302 at predetermined intervals in the circumferential direction. In the rotor 300 of FIG. 1, five slits 305 are formed in one magnetic pole (see also FIG. 2).

  The length of the five slits 305 in the direction parallel to the magnetic pole center line is the longest at the slit 305 located at the magnetic pole center and gradually becomes shorter toward the gap.

  As shown in the enlarged view of FIG. 4, the radial dimension t of the slit thin portion 306 (which is a thin core portion) between the outer peripheral portion 301 a of the rotor core 301 and the slit 305 is 5 of one magnetic pole. It is the same (uniform) in the slits 305.

  In the permanent magnet embedded motor using the rotor 300, the slit 305 makes the magnetic flux density of the outer periphery of the rotor sinusoidal, thereby reducing the harmonics of the induced voltage and the cogging torque. The torque ripple was decreasing.

  The effect of the slit 305 will be described below. Magnetic flux generated from the permanent magnet 303 of the rotor 300 flows into the stator (not shown) through the outer peripheral core portion of the permanent magnet 303.

  At that time, the magnetic path of the magnetic flux generated from the permanent magnet 303 is restricted between the adjacent slits 305.

  When the slit 305 is not present, the magnetic flux generated from the permanent magnet 303 can move freely in the outer peripheral iron core of the permanent magnet 303, so that the magnetic flux easily flows, and torque ripple due to the influence thereof. Was getting worse.

  That is, the slit 305 restricts the magnetic flux generated from the permanent magnet 303 from freely moving around the outer peripheral core portion of the permanent magnet 303.

  Therefore, by changing the shape of the slit 305, the magnetic flux on the outer periphery of the rotor can be freely changed.

  However, the rotor 300 shown in FIG. 1 rotates with torque generated by the magnetic force generated from the permanent magnet 303 in the rotor 300 and the magnetic force generated from the stator (not shown). There is a problem that it is difficult to sufficiently reduce the ripple, and noise increases.

  Next, the rotor 400 of the permanent magnet embedded motor in which the slit 405 is inclined in the rotation direction will be described with reference to FIGS.

  The rotor 400 of the embedded permanent magnet motor in which the slit 405 shown in FIGS. 5 to 8 is inclined in the rotational direction includes at least a rotor core 401 and a permanent magnet 403.

  The rotor core 401 has a substantially circular cross-sectional shape as a whole, a thin electromagnetic steel plate (for example, a thickness of about 0.1 to 1.0 mm, and a non-oriented electrical steel plate (biased in a specific direction of the steel plate). The crystal axis direction of each crystal is arranged as randomly as possible so as not to exhibit magnetic properties))) is punched with a mold into a predetermined shape, and a predetermined number (multiple) is laminated.

  The rotor core 401 is formed with four permanent magnet insertion holes 402 having a rectangular cross section so as to form a quadrangle in the circumferential direction (see FIG. 7).

  A four-pole rotor 400 is formed by inserting four flat-plate-shaped permanent magnets 403 magnetized so that N poles and S poles are alternately arranged inside the permanent magnet insertion hole 402. .

  For the permanent magnet 403, for example, a rare earth mainly containing neodymium, iron, or boron is used.

  At both ends of the permanent magnet insertion hole 402, permanent magnet end gaps 404 that are connected to the permanent magnet insertion hole 402 are formed.

  A plurality of slits 405 are formed in the peripheral direction of the permanent magnet insertion hole 402 at predetermined intervals in the circumferential direction. In the rotor 400 of FIG. 5, five slits 405 are formed in one magnetic pole (see also FIG. 6).

  In the rotor 400 of FIG. 5, the slits 405 of each magnetic pole are inclined at a predetermined angle θ with respect to the magnetic pole center line in the rotation direction of the rotor 400.

  The length of the five slits 405 in the direction inclined by a predetermined angle θ with respect to the magnetic pole center line is the longest in the slit 405 located at the magnetic pole center, and gradually becomes shorter toward the gap.

  Further, as shown in the enlarged view of FIG. 8, the radial dimension t of the slit thin portion 406 (which is a thin core portion) between the outer peripheral portion 401a of the rotor core 401 and the slit 405 is 5 of one magnetic pole. It is the same (uniform) in each slit 405.

  Next, the rotor 500 of the permanent magnet embedded motor in which the slit 505 is inclined in the counter-rotating direction will be described with reference to FIGS. 9 to 12.

  The rotor 500 of the permanent magnet embedded motor in which the slit 505 shown in FIGS. 9 to 12 is inclined in the counter-rotating direction includes at least a rotor core 501 and a permanent magnet 503.

  The rotor core 501 has a substantially circular cross-sectional shape as a whole, a thin electromagnetic steel plate (for example, a thickness of about 0.1 to 1.0 mm, and a non-oriented electrical steel plate (biased in a specific direction of the steel plate). The crystal axis direction of each crystal is arranged as randomly as possible so as not to exhibit magnetic properties))) is punched with a mold into a predetermined shape, and a predetermined number (multiple) is laminated.

  In the rotor core 501, four permanent magnet insertion holes 502 having a rectangular cross section are formed so as to form a quadrangle in the circumferential direction (see FIG. 11).

  A four-pole rotor 500 is formed by inserting four flat-plate-shaped permanent magnets 503 magnetized so that N poles and S poles are alternately arranged inside the permanent magnet insertion hole 502. .

  For the permanent magnet 503, for example, a rare earth mainly containing neodymium, iron, or boron is used.

  Permanent magnet end gaps 504 connected to the permanent magnet insertion holes 502 are formed at both ends of the permanent magnet insertion holes 502.

  A plurality of slits 505 are formed in the peripheral direction of the permanent magnet insertion hole 502 at predetermined intervals in the circumferential direction. In the rotor 500 of FIG. 9, five slits 505 are formed in one magnetic pole (see also FIG. 10).

  In the rotor 500 of FIG. 9, the slits 505 of each magnetic pole are inclined at a predetermined angle θ with respect to the magnetic pole center line in the counter-rotating direction of the rotor 500.

  The length of the five slits 505 in the direction inclined by a predetermined angle θ with respect to the magnetic pole center line is the longest in the slit 505 positioned at the magnetic pole center and gradually decreases toward the poles.

  Further, as shown in the enlarged view of FIG. 12, the radial dimension t of the slit thin portion 506 (which is a thin core portion) between the outer peripheral portion 501a of the rotor core 501 and the slit 505 is 5 of one magnetic pole. The slits 505 are the same (uniform).

  In FIG. 13, the rotor 300 with the slit 305 not inclined, the rotor 400 with the slit 405 inclined in the rotation direction, and the rotor 500 with the slit 505 inclined in the rotation direction with respect to the rotor rotation angle [deg]. Torque [Nm] is shown.

  As shown in FIG. 13, for example, the torque waveform of the rotor 400 in which the slit 405 is inclined by a predetermined angle θ in the rotation direction does not change significantly compared to the rotor 300 in which the slit 305 is not inclined. It can be confirmed that the phase is shifted (the phase is advanced). This indicates that the magnetic flux density distribution on the rotor surface does not change greatly and only the phase changes (the phase advances).

  As shown in FIG. 13, for example, the rotor 500 in which the slit 505 is inclined at a predetermined angle θ in the counter-rotating direction has a larger torque waveform than the rotor 300 in which the slit 305 is not inclined. It can be confirmed that the phase is not changed and the phase is shifted (the phase is delayed). This indicates that the magnetic flux density distribution on the rotor surface does not change greatly and only the phase changes (the phase is delayed).

  That is, it is shown that the phase of the torque waveform can be changed by changing the slit angle θ. If the slit is tilted in the rotation direction of the rotor, the phase of the torque waveform advances as compared with the case where the slit is not tilted.

  Further, if the slit is tilted in the counter-rotating direction of the rotor, the phase of the torque waveform is delayed as compared with the case where the slit is not tilted.

  In FIG. 13, when the torque waveform of the rotor 400 and the torque waveform of the rotor 500 are compared, it can be seen that the phase is approximately 180 ° different.

  From the above, in one rotor, combining the magnetic pole with the slit angle θ tilted in the rotation direction and the magnetic pole with the slit angle θ tilted in the anti-rotation direction offsets the peak portion and torque ripple Is expected to be reduced.

  For example, by setting the inclination of the slits of adjacent magnetic poles so that one is in the rotational direction and the other is in the counter-rotating direction, the phase of torque generated at each magnetic pole is advanced and the other is delayed. It is expected that torque ripple can be reduced by canceling out the torque.

  14 to 20 show the first embodiment. FIG. 14 is a cross-sectional view of the rotor 100 of the permanent magnet embedded motor, FIG. 15 is an enlarged view of a portion A in FIG. 14, and FIG. FIG. 17 is an enlarged view of a portion C in FIG. 14, FIG. 18 is an enlarged view of a portion D in FIG. 14, FIG. 19 is a transverse cross-sectional view of the rotor core 101 in FIG. FIG. 21 is an enlarged view of part B of FIG. 19, FIG. 22 is an enlarged view of part C of FIG. 19, FIG. 23 is an enlarged view of part D of FIG. 19, and FIG. 24 compares the torques of the rotors 100, 400, and 500. 25 is a cross-sectional view of a rotor 200 of a permanent magnet embedded motor according to a modification, FIG. 26 is an enlarged view of a portion A in FIG. 25, FIG. 27 is an enlarged view of a portion B in FIG. 25 is an enlarged view of part C, FIG. 29 is an enlarged view of part D of FIG. 25, FIG. 30 is a transverse sectional view of the rotor core 201 of FIG. 25, and FIG. Figure 32 is enlarged view of B part of FIG. 30, FIG. 33 C part enlarged view of FIG. 30, FIG. 34 is a D part enlarged view of FIG. 30.

  The rotor 100 of the interior permanent magnet motor according to the first embodiment will be described with reference to FIGS.

  The rotor 100 of the embedded permanent magnet motor shown in FIGS. 14 to 23 includes at least a rotor core 101 and a permanent magnet 103.

  The rotor core 101 has a substantially circular cross-sectional shape as a whole, a thin electromagnetic steel plate (for example, a thickness of about 0.1 to 1.0 mm, and a non-oriented electrical steel plate (biased in a specific direction of the steel plate). The crystal axis direction of each crystal is arranged as randomly as possible so as not to exhibit magnetic properties))) is punched with a mold into a predetermined shape, and a predetermined number (multiple) is laminated.

  The rotor core 101 is formed with four permanent magnet insertion holes 102 having a rectangular cross section so as to form a square in the circumferential direction (see FIG. 19).

  A four-pole rotor 100 is formed by inserting four flat-plate-shaped permanent magnets 103 magnetized so that N poles and S poles are alternately arranged inside the permanent magnet insertion hole 102. .

  For the permanent magnet 103, for example, a rare earth mainly composed of neodymium, iron, or boron is used.

  At both ends of the permanent magnet insertion hole 102, permanent magnet end gaps 104 connected to the permanent magnet insertion hole 102 are formed.

  A plurality of slits 105 are formed at predetermined intervals in the circumferential direction in the outer peripheral iron core portion of the permanent magnet insertion hole 102. In the rotor 100 of FIG. 14, five slits 105 are formed in one magnetic pole (see also FIGS. 15 to 18).

  In the rotor 100 of FIG. 14, the slit 105 of the magnetic pole of the A part is inclined at a predetermined angle θ with respect to the magnetic pole center line in the rotation direction of the rotor 100 (see FIGS. 15 and 20).

  Further, the slit 105 of the magnetic pole of the B part adjacent to the clockwise part of the A part is inclined at a predetermined angle θ with respect to the magnetic pole center line in the counter-rotating direction of the rotor 100 (see FIGS. 16 and 21). .

  Further, the slit 105 of the magnetic pole of the C part adjacent to the B part in the clockwise direction is inclined at a predetermined angle θ with respect to the magnetic pole center line in the rotational direction of the rotor 100 (see FIGS. 17 and 22).

  Further, the slit 105 of the magnetic pole of the D portion adjacent to the clockwise direction of the C portion is inclined at a predetermined angle θ with respect to the magnetic pole center line in the counter-rotating direction of the rotor 100 (see FIGS. 18 and 23). .

  The length of the five slits 105 in the direction inclined by a predetermined angle θ with respect to the magnetic pole center line is the longest in the slit 105 located at the magnetic pole center and gradually becomes shorter toward the gap.

  Further, as representatively shown in the enlarged view of FIG. 20, the dimension t in the radial direction of the slit thin portion 106 (which is a thin core portion) between the outer peripheral portion 101a of the rotor core 101 and the slit 105 is one. It is the same (uniform) in the five slits 105 of the magnetic pole.

  FIG. 24 shows the result of comparing the torques of the rotors 100, 400, and 500. As shown in FIG. 24, the torque of the rotor 100 includes the torque of the rotor 400 of the embedded permanent magnet motor in which the slit 405 is inclined in the rotational direction and the permanent magnet embedded in which the slit 505 is inclined in the counter-rotating direction. This is a combination of the torque of the rotor 500 of the embedded motor.

  It can be seen that the harmonic component of the torque is canceled and the torque ripple is reduced by adding the torque of the rotor 400 whose phase is approximately 180 ° different (shifted) and the torque of the rotor 500. .

  From the above, the slit 105 is inclined in the rotation direction of the rotor 100 by a predetermined angle θ with respect to the magnetic pole center line, and the slit 105 is in the counter rotation direction of the rotor 100 with respect to the magnetic pole center line. By alternately combining magnetic poles inclined at a predetermined angle θ, torque ripple can be reduced.

  Next, a rotor 200 of a permanent magnet embedded motor according to a modification will be described with reference to FIGS.

  In the rotor 200 of the modified permanent magnet embedded motor, each slit of one magnetic pole is inclined toward the magnetic pole center line, and the intersection of the extension lines of each slit exists outside the rotor 200.

  Further, the intersection of the extension lines of the slits deviates from the magnetic pole center line by a predetermined distance. In the adjacent magnetic poles, the direction in which the intersection of the extension lines of the slits is different from the magnetic pole center line is different.

  The rotor 200 of the permanent magnet embedded motor shown in FIGS. 25 to 34 includes at least a rotor core 201 and a permanent magnet 203.

  The rotor core 201 has a substantially circular cross-sectional shape as a whole, a thin electromagnetic steel plate (for example, a thickness of about 0.1 to 1.0 mm, a non-oriented electrical steel plate (biased in a specific direction of the steel plate). The crystal axis direction of each crystal is arranged as randomly as possible so as not to exhibit magnetic properties))) is punched with a mold into a predetermined shape, and a predetermined number (multiple) is laminated.

  In the rotor core 201, four permanent magnet insertion holes 202 having a rectangular cross section are formed so as to form a quadrangle in the circumferential direction (see FIG. 30).

  A four-pole rotor 200 is formed by inserting four flat-plate-shaped permanent magnets 203 magnetized so that N poles and S poles are alternately arranged inside the permanent magnet insertion hole 202. .

  For the permanent magnet 203, for example, a rare earth mainly composed of neodymium, iron or boron is used.

  At both ends of the permanent magnet insertion hole 202, permanent magnet end gaps 204 that are connected to the permanent magnet insertion hole 202 are formed.

  A plurality of slits 205 are formed in the peripheral direction of the permanent magnet insertion hole 202 at predetermined intervals in the circumferential direction. In the rotor 200 of FIG. 25, five slits 205 are formed in one magnetic pole (see also FIGS. 26 to 29).

  Although the effect of magnetic saturation can be alleviated by making the slits substantially parallel, in order to make the magnetic flux density at the outer periphery of the rotor closer to a sinusoidal shape, each slit is also tilted toward the magnetic pole center.

  In a rotor of a general embedded permanent magnet motor in which each slit is inclined toward the magnetic pole center side, an intersection point on the extension line of the slit exists at the magnetic pole center.

  The rotor 200 of the interior permanent magnet motor according to the modification is characterized in that the intersection of the extension lines of the slits 205 is arranged at a predetermined distance from the magnetic pole center line. In the adjacent magnetic poles, the direction in which the intersection of the extension lines of the slits 205 deviates from the magnetic pole center line is also different.

  In the rotor 200 of FIG. 25, the intersection of the extension lines of the slits 205 of the magnetic poles of the A portion is deviated by a predetermined distance W from the magnetic pole center line in the rotor rotation direction (see FIGS. 26 and 31).

  Further, in the rotor 200 of FIG. 25, the intersection of the extension lines of the slits 205 of the B portion magnetic pole is deviated from the magnetic pole center line by a predetermined distance W in the counter-rotating direction of the rotor (see FIGS. 27 and 32). .

  Further, in the rotor 200 of FIG. 25, the intersection of the extension lines of the slits 205 of the magnetic pole of the C section is deviated by a predetermined distance W from the magnetic pole center line in the rotation direction of the rotor (see FIGS. 28 and 33).

  Further, in the rotor 200 of FIG. 25, the intersection of the extension lines of the slits 205 of the magnetic poles of the D portion is deviated from the magnetic pole center line by a predetermined distance W in the counter-rotating direction of the rotor (see FIGS. 29 and 34). .

  The length of the five slits 205 in the direction inclined by a predetermined angle with respect to the magnetic pole center line is longest in the slit 205 located at the magnetic pole center and gradually becomes shorter toward the gap.

  As representatively shown in the enlarged view of FIG. 31, the radial dimension t of the slit thin portion 206 (which is a thin core portion) between the outer peripheral portion 201a of the rotor core 201 and the slit 205 is one. It is the same (uniform) in the five slits 205 of the magnetic pole.

  In the rotor 200 of the modified example having such a configuration, the torque waveforms of the A part and the C part and the torque waveforms of the B part and the C part are changed by approximately 180 °, and the harmonic component of the torque is canceled out. Can be reduced.

  In addition, the rotor of the present embodiment cancels the harmonic component of the torque by changing the torque phase of the magnetic pole adjacent to a certain magnetic pole existing in the rotor. Therefore, the slit shape of the adjacent magnetic poles may be set to a relationship that cancels the harmonics of the torque, and the effect can be shown when the slit shape of the adjacent magnetic poles is different. In other words, if the slit shape of a certain magnetic pole is asymmetric with the slit shape of the adjacent magnetic pole, the effect is obtained.

  Further, if the slit is asymmetric with respect to the magnetic pole center and is symmetrical with respect to the distance between the poles, it is effective for changing the phase without changing the torque waveform, and further effective. be able to.

  In addition, the interval between the slits is often set to such an extent that magnetic saturation is not caused. Therefore, by making the slits of the magnetic poles substantially parallel and making the distance between the slits constant, the influence of magnetic saturation can be mitigated, and an increase in current can be suppressed and high efficiency can be achieved.

  Further, as an effect of the present embodiment, the harmonic component of the induced voltage can be reduced by the slit and the harmonic iron loss can be reduced, so that a highly efficient rotor can be obtained.

  Further, since the rotor with low vibration can be obtained by reducing the torque ripple, the life of the rotor can be extended.

  Moreover, although the rotor demonstrated above was a rotor with 4 poles, even if it is a rotor other than 4 poles, torque ripple can be reduced by applying the shape of this Embodiment. And a rotor with high efficiency and low noise can be obtained.

  In the present embodiment, the radial dimension t of the thin slit portion (thin core portion) between the outer periphery of the rotor core and the slit is the same (uniform) in the five slits of one magnetic pole. However, even if it is not uniform, the same effect can be exhibited.

  In addition, the stator winding (not shown) can be effective with either distributed winding or concentrated winding.

  In addition, when a sintered rare earth magnet is used as a permanent magnet, the sintered rare earth magnet has a high magnetic force, so that the magnetic flux density of the rotor is higher than when other magnets are used, and the influence of the slit is increased.

  Therefore, when a sintered rare earth magnet is used for the rotor, the effect can be further improved.

  Further, by mounting the electric motor (for example, a permanent magnet embedded motor) using the rotor of the first embodiment on a compressor such as a refrigeration cycle apparatus or a blower such as an air conditioner, high efficiency and low cost are achieved. A long-life compressor and blower can be obtained.

  DESCRIPTION OF SYMBOLS 100 Rotor, 101 Rotor core, 101a outer periphery, 102 Permanent magnet insertion hole, 103 Permanent magnet, 104 Permanent magnet end space, 105 Slit, 106 Slit thin part, 200 Rotor, 201 Rotor core, 201a Outer periphery , 202 Permanent magnet insertion hole, 203 Permanent magnet, 204 Permanent magnet end gap, 205 slit, 206 slit thin part, 300 rotor, 301 rotor core, 301a outer peripheral part, 302 permanent magnet insertion hole, 303 permanent magnet, 304 Permanent magnet end gap, 305 slit, 306 slit thin part, 400 rotor, 401 rotor core, 401a outer periphery, 402 permanent magnet insertion hole, 403 permanent magnet, 404 permanent magnet end gap, 405 slit, 406 slit thin wall Part, 500 rotor, 501 rotor iron , 501a outer peripheral portion, 502 a permanent magnet insertion hole, 503 permanent magnet, 504 a permanent magnet end gap, 505 slit, 506 slit the thin portion.

Claims (10)

A rotor core formed by laminating a predetermined number of electromagnetic steel sheets punched into a predetermined shape;
A plurality of permanent magnet insertion holes formed along the outer periphery of the rotor core;
Permanent magnet end gaps provided at both ends of the permanent magnet insertion hole;
A permanent magnet inserted into the permanent magnet insertion hole;
A plurality of slits formed in the iron core portion outside the permanent magnet insertion hole,
The plurality of slits are formed substantially in parallel and are inclined at a predetermined angle with respect to the magnetic pole center line,
And have you the adjacent magnetic poles, the plurality of slits of one magnetic pole, the formed inclined at a prescribed angle in the rotational direction with respect to the magnetic pole center line, the plurality of slits of the other magnetic pole, the magnetic pole center line A rotor of an embedded permanent magnet motor, wherein the rotor is formed to be inclined at a predetermined angle in the counter-rotating direction. The plurality of slits of the one magnetic pole and the plurality of slits of the other magnetic pole respectively rotate and counter-rotate so that the phase of the torque waveform representing the torque with respect to the rotation angle of the rotor is shifted by approximately 180 degrees. Inclined at a predetermined angle to the direction
The rotor of a permanent magnet embedded motor according to claim 1. A rotor core formed by laminating a predetermined number of electromagnetic steel sheets punched into a predetermined shape;
A plurality of permanent magnet insertion holes formed along the outer periphery of the rotor core;
Permanent magnet end gaps provided at both ends of the permanent magnet insertion hole;
A permanent magnet inserted into the permanent magnet insertion hole;
A plurality of slits formed in the iron core portion outside the permanent magnet insertion hole,
The plurality of slits are formed so that each extension line intersects at an intersection located outside the rotor, and the intersection is formed with a predetermined distance from the magnetic pole center line,
And have you the adjacent magnetic poles, the plurality of slits of one magnetic pole, the intersection is formed shifted by a predetermined distance in the rotational direction from the magnetic pole center line, the plurality of slits of the other magnetic pole, the intersection magnetic pole center A rotor of an embedded permanent magnet motor, wherein the rotor is formed at a predetermined distance from the wire in the counter-rotating direction. The intersection of the plurality of slits of the one magnetic pole and the plurality of slits of the other magnetic pole is such that the phase of the torque waveform representing the torque with respect to the rotation angle of the rotor is shifted by approximately 180 degrees. Are formed at a predetermined distance from each other in the rotation direction and the counter-rotation direction.
The rotor of a permanent magnet embedded motor according to claim 3. The permanent dimension according to any one of claims 1 to 4, wherein a dimension in a radial direction of a thin slit portion between the outer peripheral portion of the rotor core and the slit is uniform in all slits of one magnetic pole. Rotor of magnet-embedded motor. 2. The length of the slit in a direction inclined at a predetermined angle with respect to the magnetic pole center line is longest in the slit located at the magnetic pole center, and gradually decreases toward the gap. A rotor of a permanent magnet embedded motor according to any one of claims 1 to 5 . The shape of the slit, interior permanent magnet motor rotor according to any one of claims 1 to 6, characterized in that a line symmetry with respect to the machining gap centerline. Wherein the permanent magnet, the permanent magnet-embedded motor rotor according to any one of claims 1 to 7, characterized by using a rare earth magnet. A blower comprising the rotor of a permanent magnet embedded motor according to any one of claims 1 to 8 . A compressor comprising the rotor of a permanent magnet embedded motor according to any one of claims 1 to 8 .

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