JP5383915B2 - Permanent magnet type rotating electric machine - Google Patents

Description

  The present invention relates to a rotating electrical machine such as a vehicle motor, and more particularly to a structure of a rotor of a rotating electrical machine in which a permanent magnet is disposed inside the rotor.

  Conventionally, a permanent magnet type motor using a permanent magnet has been used as a field generating means for a rotor. Since the centrifugal force at the time of high-speed rotation of the rotor of the permanent magnet type motor acts on the permanent magnet, the magnet embedded structure having a magnet holding structure in which the permanent magnet is embedded in the rotor to improve the centrifugal force resistance. A retractable motor (Interior Permanent Magnet Motor: hereinafter referred to as “IPM motor”) has been proposed (for example, Patent Document 1 below).

  In the IPM motor described in Patent Document 1, it has been proposed to provide a groove on the rotor surface. When the angle of the groove is set to an electrical angle of 44 degrees to 53 degrees from the center line of the magnetic pole, no load induced voltage is generated. It is described that when the harmonic component is reduced and the groove angle is set to an electrical angle of 40 to 44 degrees from the center line of the magnetic pole, the torque ripple is reduced.

JP 2009-118731 A

  In the conventional IPM motor including the IPM motor described in Patent Document 1, since the retention force against the centrifugal force of the permanent magnet is obtained only by the strength of the rotor core in the rotor surface direction, the centrifugal force of the permanent magnet is Consideration is needed to maintain strength against force. For this reason, in the conventional IPM motor, when adopting a structure in which a groove is provided on the rotor surface as in Patent Document 1, it is necessary to provide a permanent magnet on the inner side (center side) of the rotor. However, when the permanent magnet is provided inside the rotor, there is a problem in that the leakage magnetic flux at both ends of the permanent magnet is increased and the driving torque is reduced.

  The present invention has been made in view of the above, and an object of the present invention is to provide a permanent magnet type rotating electrical machine capable of reducing a no-load induced voltage while maintaining strength against centrifugal force.

  It is another object of the present invention to provide a permanent magnet type rotating electrical machine that can suppress a decrease in driving torque.

  In order to solve the above-described problems and achieve the object, a permanent magnet type rotating electrical machine according to the present invention includes a stator having a plurality of slots for accommodating a stator coil in a slot, and a rotating gap in the stator. A rotor core disposed rotatably through the rotor core, and a rotor in which three or more permanent magnets are embedded per pole in the rotor core, and the rotor core has the permanent core Magnet insertion holes for embedding magnets are arranged in a generally U shape toward the outer peripheral surface of the rotor, and a cavity is formed on the side surface of the permanent magnet embedded in each magnet insertion hole, and the rotation In the vicinity of the outer peripheral portion of the core, a pair of holes having a symmetrical shape with respect to the center line between the magnetic poles is provided for each magnetic pole, and the number of pole pairs of the permanent magnet is p, and the number of pole pairs p is 3 or more. The number of slots of the stator that takes an integer multiple where m is the (m / p + 1) -order harmonic component and the (m / p + 1) -order harmonic component of the no-load induced voltage generated in the stator due to the rotation of the rotor. Is provided at a position where the sum of the amplitudes of the two is minimized or in the vicinity thereof.

  According to the present invention, there is an effect that the no-load induced voltage can be reduced while maintaining the strength against centrifugal force.

FIG. 1 is a cross-sectional view of a permanent magnet type electric motor that is an example of a permanent magnet type rotating electrical machine according to the first embodiment. FIG. 2 is a schematic cross-sectional view showing the structure of the rotor in the permanent magnet type electric motor shown in FIG. FIG. 3 is an enlarged view of a portion indicated by a broken line in the rotor of FIG. FIG. 4 is an enlarged view of a portion corresponding to FIG. 3 when a permanent magnet is inserted. FIG. 5 is a partially enlarged view in which a peripheral portion of the magnet insertion hole shown in FIG. 3 is enlarged. FIG. 6 is a diagram for explaining the influence of leakage magnetic flux in the first embodiment. FIG. 7 is a diagram for explaining the influence of leakage magnetic flux in a conventional example as a comparative example. FIG. 8 is a graph showing a simulation result regarding the sum of amplitudes of the (n−1) -order harmonic component and the (n + 1) -order harmonic component of the no-load induced voltage that changes according to the position of the hole. FIG. 9 is a diagram for explaining the electrical angle representing the position of the hole. FIG. 10 is a schematic cross-sectional view illustrating a part of the structure of the rotor of the permanent magnet type rotating electric machine according to the third embodiment.

  A permanent magnet type rotating electrical machine according to an embodiment of the present invention will be described below with reference to the accompanying drawings. In addition, this invention is not limited by embodiment shown below.

Embodiment 1 FIG.
1 is a cross-sectional view of a permanent magnet type electric motor that is an example of a permanent magnet type rotating electrical machine according to a first embodiment of the present invention, and FIG. 2 shows the structure of a rotor in the permanent magnet type electric motor shown in FIG. FIG. 3 is an enlarged view of a portion indicated by a broken line portion in the rotor of FIG. 2, and FIG. 4 is an enlarged view of a portion corresponding to FIG. 3 when a permanent magnet is inserted. FIG.

  The permanent magnet type electric motor 1 according to the first embodiment includes a stator 2 and a rotor 5. The stator 2 has a stator core 3 having a cylindrical shape, and this stator core 3 is formed by forming 36 teeth 3b at an equal pitch and intermittently on the inner peripheral side thereof. 36 slots 3a are formed. In the slot 3a, the stator coil 4 is wound and stored so as to include a predetermined number of teeth 3b therein.

  The rotor 5 is produced by, for example, laminating and integrating a predetermined number of magnetic steel plates, the outer peripheral surface forms a cylindrical surface, and 18 magnet insertion holes 7 (see FIGS. 2 and 3) are arranged at an equiangular pitch. The rotor core 6 formed as described above and permanent magnets 8 (8a to 8c) housed in the respective magnet insertion holes 7 can be rotated through the rotation gap 18 with respect to the stator 2. It is arranged to become.

  Here, as shown in FIG. 3, the magnet insertion hole 7 has two magnet insertion holes 7 a and 7 c at both ends of one magnet insertion hole 7 b, and is arranged on the outer circumferential surface (outer circumferential direction) of the rotor 5. Six sets are arranged in a generally U shape so as to open toward the front. And while the direction of the magnetic flux by the permanent magnets 8a to 8c, which is a set of first permanent magnets, is magnetized (magnetized) in a direction to converge toward the outer peripheral surface of the rotor 5, an adjacent set (second set) The permanent magnets 16 a to 16 c of the permanent magnets are magnetized in a direction in which the direction of the magnetic flux extends toward the center of the rotor 5. That is, in the rotor in the permanent magnet type electric motor according to the first embodiment, the permanent magnet group magnetized in the direction in which the direction of the magnetic flux by the permanent magnet converges toward the outer peripheral surface of the rotor, and the central portion of the rotor Permanent magnet groups that are magnetized in a direction that spreads out are arranged alternately.

  Further, on both side surfaces of the permanent magnets 8a to 8c embedded in the magnet insertion holes 7a to 7c, there are the cavity portions 9 as shown in FIG. 4 (the cavity portions 9a1 and 9a2 and the permanent magnets 8b Cavities 9b1 and 9b2 are formed on both side surface portions, and cavity portions 9c1 and 9c2) are formed on both side surface portions of the permanent magnet 8c.

  Further, of the magnet insertion holes 7a to 7c, holes 20 (20a and 20b) that can reduce the no-load induced voltage are provided in the periphery of the magnet insertion holes 7a and 7c located at both ends. .

  In FIG. 1, 36 slots 3 a are arranged at an equiangular pitch in the circumferential direction of the stator 2, and 18 permanent magnets 8 are embedded in the circumferential direction of the rotor 5 (the number of pole pairs = The electric motor (3) (six slots per pole and three permanent magnets per pole) is shown as an example, but the number of poles of the motor, the number of slots, the number of permanent magnets, etc. It is not limited and any number of selections are possible.

  The reason why the direction of magnetization by the permanent magnet group is configured as described above is to make the induced voltage of the stator coil sinusoidal, and in applications where the induced voltage of the stator coil does not need to be sinusoidal. This is not the case. That is, the magnetization directions of the permanent magnet groups magnetized in the direction toward the outer peripheral surface of the rotor or in the direction toward the center of the rotor may be parallel.

  Next, more detailed positions of the holes 20a and 20b will be described with reference to FIG. 5 taking the hole 20a as an example. FIG. 5 is a partially enlarged view in which a peripheral portion of the magnet insertion hole shown in FIG. 3 is enlarged.

  In FIG. 5, a center line 30 a between magnetic poles is drawn through the center of the rotor core 6 and equidistant from one permanent magnet group and another permanent magnet group. The hole 20a is provided on the right side of the paper with respect to the bridge portion 11a formed between the magnet insertion hole 7a and the outer peripheral end of the rotor core 6, that is, on the opposite side of the center line 30a between the magnetic poles with respect to the bridge portion 11a. Yes. The position of the hole 20a has a preferable position from a mechanical viewpoint and an electrical viewpoint.

  Here, the mechanical viewpoint is a viewpoint of centrifugal force strength, and the electrical viewpoint is a viewpoint regarding leakage flux and no-load induced voltage. When the hole 20a is provided on the side close to the outer peripheral end of the rotor core 6, the centrifugal force strength of the rotor core 6 decreases. Therefore, when the centrifugal force strength of the rotor core 6 becomes a problem, it is required to arrange the hole 20a as close to the center of the rotor core 6 as possible.

  The example shown in FIG. 5 is an example in the case where it is provided closer to the center portion than the curve 24a that passes through the end portion 28a closest to the outer peripheral portion of the magnet insertion hole 7a and is virtually drawn to the outer peripheral end of the rotor core 6. And is one of the preferred embodiments. This is because the magnet insertion hole 7a is usually designed in consideration of the strength of centrifugal force, and the diameter of the hole 20a is, for example, a △ ΔkW class motor of about XX mm. It is very small compared to the size of the hole 7a. For this reason, as long as the magnet insertion hole 7a is arranged closer to the center than the curve 24a, the problem of reduced centrifugal force strength does not occur. In addition, when there is a margin in the centrifugal force strength, it is needless to say that a part or all of the hole 20a may be located on the outer peripheral side from the curve 24a according to the margin of the centrifugal force strength. .

  6 and 7 are diagrams for explaining a problem related to the leakage magnetic flux from the electrical viewpoint mentioned above, and FIG. 6 is a diagram for explaining the influence of the leakage magnetic flux in the first embodiment. FIG. 7 is a diagram for explaining the influence of leakage magnetic flux in a conventional example as a comparative example.

  The magnetic flux generated by the permanent magnets 8a to 8c returns to the rotor core 6 again (not shown) after passing through the core back portion 15 (see FIG. 1) of the stator core 3. However, as shown in FIG. 6, a part of the magnetic flux stays inside the rotor core 6 so as to return to the permanent magnet 8 without going to the core back portion 15, and in the rotor core 6, a loop and There is a leakage flux 12 that becomes The leakage magnetic flux 12 does not contribute to torque and causes an increase in iron loss, so it is preferable to suppress it as much as possible.

  Therefore, in the rotor 5 according to the present embodiment, as shown in FIG. 4, with respect to the permanent magnet group arranged in a substantially U shape, the cavity portion on both side surface portions of the magnet insertion hole 7 is more than the cavity portion other than both side surface portions. Also try to get bigger. In a specific configuration, the hollow portions 9b1 and 9b2 generated by embedding the permanent magnet 8b in the magnet insertion hole 7b are approximately equal in size, and the hollow portion generated by embedding the permanent magnet 8a in the magnet insertion hole 7a. In 9a1 and 9a2, the magnet insertion hole 7a is formed so that the cavity 9a1 is larger, and the cavity 9c1 and 9c2 generated by embedding the permanent magnet 8c in the magnet insertion hole 7c is the same as the cavity 9c2. The magnet insertion hole 7c is formed so as to be larger.

  In other words, in the rotor 5 according to the present embodiment, the cavity (for example, the cavity 9a1) formed on the outer peripheral side of the rotor core 6 is formed on the center side of the rotor core 6. The shape of the magnet insertion hole 7 is formed so as to be a larger space than the hollow portions (for example, the hollow portions 9a2, 9b1,...). According to the rotor core 6 configured as described above, the leakage magnetic flux 12 due to the permanent magnet 8 is generated by the bridge portion 10a formed between the permanent magnets 8a and 8b and the bridge portion formed between the permanent magnets 8b and 8c. 10b and the bridge portions 11a and 11b respectively formed between the permanent magnets 8a and 8c and the outer peripheral surface of the rotor core 6 serve as magnetic flux paths. Therefore, it is possible to reduce the leakage flux 12 by narrowing these magnetic flux paths.

  Here, among the bridge portions 10a, 10b and 11a, 11b, particularly the bridge portions 11a, 11b are traded off with the centrifugal force intensity. However, in the rotor 5 in the present embodiment, the number of permanent magnets is divided into three to reduce the weight of each permanent magnet, and the three permanent magnets have a curvature as shown in the figure. Are arranged side by side in a generally U shape, so that the thickness of the bridge portions 11a and 11b can be reduced compared to the conventional configuration, and the leakage magnetic flux passing through these bridge portions can be reduced. Become.

  On the other hand, FIG. 7 shows a portion corresponding to FIG. 6 of the rotor core disclosed in Patent Document 1, and in this rotor core 106, permanent magnets 108a and 108b, which are a set of permanent magnets, are arranged on the outer peripheral surface. It arrange | positions in V shape toward. Here, since the rotor core disclosed in Patent Document 1 is a set of two permanent magnets, in order to obtain the same field force, one piece is used rather than that in the first embodiment. The weight per hit increases. In Patent Document 1, since the groove 120 is provided on the outer peripheral surface of the rotor core 106, the centrifugal force strength is smaller than that of the rotor core 6 of the first embodiment. Therefore, the positions of the permanent magnets 108a and 108b in the rotor core of Patent Document 1 need to be provided closer to the center than in the first embodiment. At this time, the leakage magnetic flux 112 staying inside the rotor core 106 without returning to the opposing stator core 106 and returning to itself becomes larger than the leakage magnetic flux 12 according to the present embodiment as shown in FIG. When the leakage magnetic flux 112 is increased, the rotational torque is reduced and the iron loss is also increased. Therefore, the adverse effect caused by providing the groove 120 on the outer peripheral surface of the rotor core 106 is also increased.

  Next, the no-load induced voltage from an electrical viewpoint will be described. FIG. 8 shows the (n−1) -order harmonic component (11th-order harmonic component in the example of FIG. 8) and the (n + 1) -order harmonic component of the no-load induced voltage that changes according to the position of the hole 20a. It is a graph which shows the simulation result regarding the amplitude sum with (in the example of FIG. 8 13th harmonic component). Here, the order n is an integer represented by the equation n = m / p, where m is the number of slots of the stator and p is the number of pole pairs of the permanent magnet group. In the permanent magnet type rotating electrical machine of the present embodiment, the number of slots of the stator is 36 and the number of pole pairs of the permanent magnet group is 3, so that n = (36/3) = 12, and in the example of FIG. , The amplitude sum of the 11th harmonic component and the 13th harmonic component is shown as an evaluation index. FIG. 8 also shows the fundamental wave component of the no-load induced voltage that is largely related to the torque (magnet torque) generated by the permanent magnets 8a to 8c.

  In FIG. 8, the angle θ shown on the horizontal axis represents the position of the hole 20 a with the center line 30 a between the magnetic poles as the reference axis in electrical angle (see FIG. 9). Although FIG. 9 shows the adjacent magnetic pole center line 30b, the electrical angle between the magnetic pole center lines 30a and 30b is 180 degrees, and the center line between the magnetic poles is located at the symmetrical position of the hole 20a. Since the hole 20b having 30b as the reference axis is provided, the range of the electrical angle θ related to the hole 20a is in the range of 0 to 90 °.

  Referring to the waveform of FIG. 8, it can be seen that the harmonic component of the no-load induced voltage has a minimum value at electrical angles θ = θ1, θ2, θ3 (θ1 <θ2 <θ3).

  Here, when the hole 20a is in the vicinity of the magnetic pole (θ = θ1), the harmonic component of the no-load induced voltage is suppressed and the fundamental component is large, so the magnet torque generated by the permanent magnet is hardly reduced. . However, the torque (reluctance torque) generated by the magnetic flux generated between the steel portion on the surface of the rotor core 6 and the stator coil is reduced by the gap formed by the hole 20a. Therefore, in order to suppress the no-load induced voltage without impairing the reluctance torque, the electrical angle θ representing the position of the hole 20a needs to satisfy θ> A as shown in FIG. In addition, this A is the position closest to the outer peripheral side end of the rotor core 6 and is based on the center line 30a between the magnetic poles of the end 28a that is farthest from the center line 30a between the magnetic poles. Is an electrical angle. Therefore, in the example of FIG. 8, the preferred position of the hole 20a is the electrical angle θ2, θ3 or an electrical angle position in the vicinity thereof.

  As described above, the hole 20b is provided at a symmetrical position of the hole 20a with the center line 30b between the magnetic poles as a reference axis. Therefore, for example, when the hole 20a is provided at the electrical angle θ2 with reference to the center line 30a between the magnetic poles or a position near the electrical angle θ2, the hole 20b is formed at the electrical angle −θ2 with reference to the center line 30b between the magnetic poles or a position near the electrical angle θ2. When the hole 20a is provided at or near the electrical angle θ3 with respect to the center line 30a between the magnetic poles, the hole 20b is provided at the electrical angle −θ3 with reference to the center line 30b between the magnetic poles or a position near the electrical angle θ3. Will be provided.

  That is, the holes 20a and 20b are between the permanent magnets 8a to 8c (permanent magnet group) arranged side by side in a substantially U shape and the outer peripheral portion of the rotor core 6, and the number of pole pairs of the permanent magnets is determined. where p is the number of slots in the stator and m is the position where the sum of amplitudes of the (m / p-1) order harmonic component and the (m / p + 1) order harmonic component of the no-load induced voltage is minimized. Or it arrange | positions in the vicinity position. The value of m / p takes an integer value of 3 or more, and this value never becomes a real number.

  Moreover, said arrangement position regarding hole 20a, 20b is an arrangement position for suppressing a no-load induced voltage, without impairing reluctance torque. Therefore, in applications where the reluctance torque may be sacrificed to some extent, the position where the no-load induced voltage is minimized or in the vicinity thereof is the position outside the permanent magnet group arranged in a generally U shape. It doesn't matter.

  As described above, according to the permanent magnet type rotating electrical machine of the first embodiment, when providing a pair of symmetrical holes with respect to the center line between the magnetic poles for each magnetic pole, the vicinity of the outer peripheral portion of the rotor core And the (m / p-1) order harmonic component and the (m / p + 1) order harmonic component of the no-load induced voltage when the number of pole pairs of the permanent magnet is p and the number of slots of the stator is m Since it is provided at a position where the amplitude sum with the component is minimized or in the vicinity thereof, it is possible to reduce the no-load induced voltage while maintaining the strength against the centrifugal force.

  When the stator core 3 and the rotor core 6 are manufactured, first, the magnetic steel plate constituting the stator core 3 is first punched, and then the rotor core 6 is manufactured using the remaining portion. It is. In this case, after the magnetic steel plates constituting the rotor core 6 are fixed and integrated, an operation of cutting the rotor end face is required to form the rotation gap 18 (see FIG. 1). Therefore, when forming a groove | channel like patent document 1, the groove | channel formed in a magnetic steel plate must prepare the cutting allowance at the time of cutting a rotor end part surface beforehand. In this regard, in the case of the first embodiment, the size of the hole can be determined at the stage of manufacturing the magnetic steel plate, and there is no need to pay attention to the shape of the groove on the rotor end face, so the manufacturing process. Can be simplified.

  Further, in the permanent magnet type rotating electric machine according to the first embodiment, between the permanent magnet group in which the positions of the pair of holes provided on the rotor core are arranged in a substantially U shape and the outer peripheral portion of the rotor core By doing so, the influence of a decrease in reluctance torque can be reduced, and a decrease in drive torque can be suppressed.

  In the above description, the hollow portions 9a1, 9a2, 9b1, 9b2, 9c1, and 9c2 in the holes 20a and 20b and the magnet insertion holes 7a to 7c in which the permanent magnets 8a to 8c are embedded are described as gaps. A nonmagnetic member such as an adhesive may be poured into the gap. By pouring a nonmagnetic member such as an adhesive, it becomes possible to hold the permanent magnets 8a to 8c more firmly and to increase the centrifugal force strength of the rotor core 6.

Embodiment 2. FIG.
In the first embodiment, the holes 20a and 20b that can reduce the no-load induced voltage are provided in the vicinity of the outer peripheral portion of the rotor core 6. However, the holes 20a and 20b may have a caulking structure. Good. When the holes 20a and 20b have a caulking structure, the magnetic characteristics of the caulking structure part can be made close to air. Therefore, this is equivalent to the formation of a gap in the caulking structure part and the no-load induced voltage is reduced. Occurrence can be reduced. That is, by forming the holes 20a and 20b into a caulking structure, both the action of fixing and integrating the magnetic steel plates constituting the rotor core 6 and the action of reducing the generation of no-load induced voltage are provided. The effect can be obtained.

  The caulking structure described above is optional, and a caulking structure in which a hole is formed in the caulking portion may be employed, or a caulking structure in which no hole is formed in the caulking portion may be employed.

Embodiment 3 FIG.
FIG. 10 is a schematic cross-sectional view showing a part of the structure of the rotor of the permanent magnet type rotating electric machine according to the third embodiment of the present invention. In the permanent magnet type rotating electric machine shown in the figure, grooves 32a and 32b are provided on the outer peripheral end of the rotor core 6 in place of the holes 20a and 20b shown in FIG. In addition, about another structure, it is the same as that of Embodiment 1 shown in FIG. 9, or is equivalent, and attaches | subjects and shows the same code | symbol to a common site | part.

  In FIG. 10, the positions of the grooves 32a and 32b are the same as in the first embodiment, and the (m / p-1) -order harmonic component of the no-load induced voltage that changes according to the position of the groove 32a. And a groove 32a at the position where the sum of amplitudes with the (m / p + 1) -order harmonic component is minimum or in the vicinity thereof, and the symmetrical position of the groove 32a with the center line 30b between the magnetic poles as the reference axis, or What is necessary is just to provide the groove | channel 32b in the vicinity position.

  The grooves 32a and 32b are preferably rectangular. If the shape of the grooves 32a and 32b is rectangular, it becomes easy to consider the cutting allowance when cutting the rotor end face, and symmetry about the shape of the groove after cutting can be easily obtained.

  Further, the configurations shown in the above first to third embodiments are examples of the configuration of the present invention, and can be combined with other known techniques, and can be combined within a range not departing from the gist of the present invention. Needless to say, the configuration may be modified by omitting the unit.

  For example, in the first to third embodiments, the configuration of the rotor having three permanent magnets per pole is illustrated, but a rotor having four or more permanent magnets per pole may be configured.

  In the first to third embodiments, the permanent magnet 8 embedded in the magnet insertion hole 7 is exemplified by a substantially rectangular shape as shown in FIG. 4, for example, but is not limited to such a rectangular shape. For example, a trapezoidal shape may be used, and a corner portion on the outer peripheral side of the permanent magnet 8 may be chamfered in accordance with the shape of the outer peripheral portion of the rotor core 6.

  As described above, the permanent magnet type rotating electrical machine according to the present invention is useful as an invention capable of reducing the no-load induced voltage while maintaining the strength against centrifugal force.

DESCRIPTION OF SYMBOLS 1 Permanent magnet type motor 2 Stator 3 Stator iron core 3a Slot 3b Teeth 4 Stator coil 5 Rotor 6,106 Rotor iron core 7,7a-7c Magnet insertion hole 8,8a-8c, 16,16a-16c, 108a , 108b Permanent magnet 9, 9a1, 9a2, 9b1, 9b2, 9c1, 9c2 Cavity part 10a, 10b, 11a, 11b Bridge part 12, 112 Leakage flux 15 Core back part 18 Rotating air gap 20, 20a, 20b Hole 24a Curve 28a End Part 30a, 30b Center line between magnetic poles 32a, 32b, 120 groove

Claims (2)

A stator having a plurality of slots for accommodating a stator coil inside the slot;
A rotor having a rotor core disposed rotatably in the stator via a rotation gap, and three or more permanent magnets embedded in each rotor core;
With
Magnet insertion holes for embedding the permanent magnets are provided in the rotor iron core so as to be arranged in a substantially U shape toward the outer peripheral surface of the rotor, and hollow portions are provided on the side surfaces of the permanent magnets embedded in the magnet insertion holes. Is formed,
In the vicinity of the outer periphery of the rotor core, a pair of holes forming a symmetrical shape with respect to the center line between the magnetic poles is provided for each magnetic pole,
When the number of pole pairs of the permanent magnet is p, and the number of slots of the stator taking an integer multiple of 3 or more of the number of pole pairs p is m,
The pair of holes has a sum of amplitudes of the (m / p-1) order harmonic component and the (m / p + 1) order harmonic component of the no-load induced voltage generated in the stator by the rotation of the rotor. From a curve that is a minimum or a position near it and passes through the end closest to the outer periphery of the magnet insertion hole located at the outermost periphery, and is virtually and parallel to the outer periphery of the rotor core. Is also provided on the center side . A stator having a plurality of slots for accommodating a stator coil inside the slot;
A rotor having a rotor core disposed rotatably in the stator via a rotation gap, and three or more permanent magnets embedded in each rotor core;
With
The rotor core is a structure in which laminated electromagnetic steel sheets are integrated by caulking,
Magnet insertion holes for embedding the permanent magnets are provided in the rotor iron core so as to be arranged in a substantially U shape toward the outer peripheral surface of the rotor, and hollow portions are provided on the side surfaces of the permanent magnets embedded in the magnet insertion holes. Formed,
When the number of pole pairs of the permanent magnet is p, and the number of slots of the stator taking an integer multiple of 3 or more of the number of pole pairs p is m,
Amplitude sum of the previous SL caulking is by rotation of the front SL rotor of no-load induced voltage generated in the stator (m / p-1) and the next harmonic component, (m / p + 1) next harmonic component the Ri position or der vicinity thereof to a minimum, and through the end closest to the outer periphery of the magnet insertion hole located at the outermost periphery are parallel and virtually pulled the outer peripheral end of the rotor core A permanent magnet type rotating electrical machine, characterized in that the permanent magnet type rotating electrical machine is provided closer to the center than the curve .

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