JP6933299B2 - Rotor structure of rotating electric machine - Google Patents

Description

The present invention relates to a rotor structure of a rotating electric machine.

JP2017-50965A discloses an embedded magnet type motor in which two permanent magnets are arranged in a V shape to form one magnetic pole. In this motor, when the line passing through the apex of the flux barrier provided at the end on the q-axis side electrically orthogonal to the d-axis formed by one magnetic pole and the center of the rotation axis is tangent A, the motor is called tangent A. It has a groove formed along the axial direction of the rotor core on the outer periphery of the rotor core with respect to the q-axis. By forming the groove in the rotor core in this way, it is possible to suppress the higher-order component of the magnet magnetic flux interlinking with the stator, so that iron loss can be reduced.

The rotor core configured as described in Patent Document 1 is effective when the magnetic pole is composed of a set of permanent magnets. However, when a magnetic pole having two layers of a set of permanent magnets is formed, the direction of the magnetic flux of the magnet changes, and depending on the groove configured as in the prior art, the effect of reducing iron loss may not always be obtained. There was a problem that it could not be done, and in some cases, the harmonics increased and the electromagnetic vibration force deteriorated.

An object of the present invention is to provide a rotor structure of a rotating electric machine capable of reducing iron loss.

The rotor structure of a rotary electric machine according to the present invention is applied to a rotor core of a rotary electric machine including a rotor core of a rotor having a plurality of magnetic poles provided in the circumferential direction and a plurality of permanent magnets constituting one magnetic pole in the rotor core. NS. One magnetic pole is composed of a first permanent magnet pair and a second permanent magnet pair, and the first permanent magnet pair is composed of a pair of permanent magnets arranged so as to spread substantially V-shaped outward in the radial direction. The two permanent magnet pairs are provided on both outer sides in the circumferential direction of the first permanent magnet pair, and are composed of a pair of permanent magnets arranged so as to spread substantially V-shaped outward in the radial direction. A first flux barrier provided on the q-axis side electrically orthogonal to the d-axis formed by one magnetic pole and a q-axis side provided on the q-axis side electrically orthogonal to the d-axis formed by one magnetic pole in the second permanent magnet pair. The second flux barrier is provided. The line connecting the q-axis end of the first flux barrier and the rotation center point of the rotor core was tangent 1, and the line connecting the d-axis end of the second flux barrier and the rotation center of the rotor core was tangent 2. Occasionally, a rotor outer peripheral groove formed along the axial direction of the rotor core is provided on the outer periphery of the rotor core between the tangent line 1 and the tangent line 2.

FIG. 1 is an explanatory diagram of a rotor structure according to the first embodiment of the present invention. FIG. 2 is an explanatory diagram showing the flow of magnetic flux of the rotor core according to the first embodiment of the present invention. FIG. 3 is a diagram showing the relationship between the iron loss and the position angle of the groove according to the first embodiment of the present invention. FIG. 4 is a modified example of the first embodiment of the present invention, and shows an example in which the flux barrier of the second layer is open to the outer periphery of the rotor core. FIG. 5 shows another modification of the first embodiment of the present invention, in which the flux barrier of the second layer communicates with the magnet hole. FIG. 6 is an explanatory diagram of a rotor structure according to a second embodiment of the present invention. FIG. 7 is a diagram showing the relationship between the torque ripple of the second embodiment of the present invention and the position angle of the groove. FIG. 8 is an explanatory diagram showing the relationship between the groove and the tangent line in the first and second embodiments of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like.

FIG. 1 is an explanatory diagram of a rotor structure of a rotary electric machine according to a first embodiment of the present invention.

FIG. 1 is a configuration diagram of a rotor (rotor) 6 included in a rotary electric machine constituting an electric motor (motor) or a generator as viewed from a cross section perpendicular to the axial direction, and is a part of the entire configuration (one pole portion). ) Is shown.

The rotary electric machine of the present embodiment is a so-called IPM (Interior Permanent Magnet) type rotary electric machine in which a permanent magnet 3 is embedded inside the rotor 6.

In the rotor 6, one magnetic pole is composed of four permanent magnets 3. One magnetic pole is composed of a first layer 50A having a first permanent magnet pair (permanent magnets 3A, 3A) and a second layer 50B having a second permanent magnet pair (permanent magnets 3B, 3B). The second layer 50B is arranged on the inner peripheral side of the rotor 6 with respect to the first layer 50A.

The first permanent magnet pair (permanent magnets 3A, 3A) is arranged so that the two permanent magnets 3A spread in a substantially V shape outward in the radial direction of the rotor 6. Similarly, the second permanent magnet pair (permanent magnets 3B and 3B) is arranged so that the two permanent magnets 3B spread outward in the radial direction of the rotor 6 in a substantially V shape. The second permanent magnet pair (permanent magnet 3B, 3B) is located on both outer sides of the rotor 6 in the circumferential direction with respect to the first permanent magnet pair (permanent magnet 3A, 3A), and the first permanent magnet pair (permanent). It is arranged at a position offset inward in the radial direction of the rotor 6 with respect to the magnets 3A and 3A).

The rotary electric machine of the present embodiment shown in FIG. 1 will be described by taking a rotor having an 8-pole structure as an example, but the number of poles is not limited to this. However, the various analysis data described below are composed of a rotor 6 having an 8-pole structure and a stator 12 having a number of slots of 48 and a stator winding wound by distributed winding. It is assumed that the analysis has been performed by applying the present invention to a rotary electric machine.

The rotor core (rotor core) 1 is formed in a cylindrical shape by a so-called laminated electromagnetic steel plate structure formed by laminating a single plate obtained by punching an electromagnetic steel plate having a thickness of several hundred μm in an annular shape in the axial direction. ..

A magnet insertion hole 2 (hereinafter, also simply referred to as a magnet hole 2) for inserting a permanent magnet 3 is formed in each single plate of the electrical steel sheet, and both ends of the magnet hole 2 in the circumferential direction and their vicinity thereof are formed. Flux barriers 4, 5 and 11 are formed in the wall.

The magnet hole 2 is a hole formed in the electromagnetic steel plate for inserting the permanent magnet 3. Two layers (first layer 50A, second layer 50B) are formed in the magnet hole 2 in the radial direction per pole, and two permanent magnets 3 are inserted into each layer.

The magnet holes 2 are arranged in the first layer 50A and the second layer 50B so as to have a substantially V shape toward the outer peripheral side of the rotor 6.

By laminating the electromagnetic steel sheets on which the magnet holes 2 are formed in the axial direction, holes for embedding the permanent magnets 3 are formed in the rotor core 1. The permanent magnet 3 is fixed to each hole formed in the rotor core 1.

In the first layer 50A, the magnetic poles formed by a set of first permanent magnet pairs (permanent magnets 3A and 3A) along the circumferential direction of the rotor 6 are equidistant to each other, and the polarities of the magnetic poles adjacent to each other are different. Arranged to be polar. Similarly, in the second layer 50B, the magnetic poles formed by the pair of second permanent magnet pairs (permanent magnets 3B and 3B) along the circumferential direction of the rotor 6 are equidistant to each other and adjacent to each other. Arranged so that the polarities are different. One magnetic pole is formed by the four permanent magnets 3 of the first layer 50A and the second layer 50B. The direction of the magnetic flux created by the four permanent magnets 3 is the d-axis, and the direction that is electrically and magnetically orthogonal to the d-axis is the q-axis.

In the first layer 50A, a set of magnet holes 2A are arranged symmetrically with respect to the d-axis, and a permanent magnet 3A is inserted into each of these magnet holes 2A. Flux barriers 4 (4A) and 5 (5A) are formed as gaps in the magnet holes 2A at the ends in the longitudinal direction. The flux barrier 4A is arranged at the end of a pair of permanent magnet pairs (permanent magnets 3A, 3A) on the d-axis side. The flux barrier 5A is arranged at the end of a pair of permanent magnet pairs (permanent magnets 3A, 3A) on the q-axis side.

Similarly, in the second layer 50B, a set of magnet holes 2B are arranged symmetrically on the d-axis, and a permanent magnet 3B is inserted into each of the magnet holes 2B. Flux barriers 4 (4B) and 5 (5B) are formed as gaps in the magnet holes 2B at the ends in the longitudinal direction. The flux barrier 4B is arranged at the end of a pair of permanent magnet pairs (permanent magnets 3B, 3B) on the d-axis side. The flux barrier 5B (end flux barrier 5B) is arranged at the end of a set of permanent magnet pairs (permanent magnets 3B, 3B) on the q-axis side.

Further, the second layer 50B includes a flux barrier 11 (separation flux barrier 11) which is a hole portion separated from the magnet hole 2B and independent of the magnet hole 2B. The flux barrier 11 is formed on the q-axis as a void portion having a shape symmetrical with respect to the q-axis.

The voids formed by the flux barriers 4, 5 and 11 have a lower magnetic permeability and a higher magnetoresistance than the magnetic steel sheet. Therefore, the flux barriers 4, 5, and 11 act as magnetic barriers that serve as resistance when the magnetic flux (flux) passes through the magnetic circuit in which the permanent magnet 3 constitutes the rotor 6.

The flux barriers 4, 5 and 11 configured in this way form a magnetic barrier at an appropriate position. Specifically, in the first layer 50A, the flux barriers 4A and 5A form a magnetoresistive group with respect to the permanent magnet 3A, and in the second layer 50B, the flux barriers 4B, 5B and 11 form a magnetic resistance group with respect to the permanent magnet 3B. Form a reluctance group.

With such a configuration, the magnetic flux emitted from the permanent magnets 3 serves as a magnetic barrier when leaking to the different electrode side of the permanent magnets 3, so that the magnetic fluxes emitted from the respective permanent magnets 3 are leaked to the stator 12 side without leakage. Can be properly interlocked with. This improves the torque performance of the rotary electric machine.

Further, in the flux barrier 5B in the second layer 50B of the present embodiment, the portion closest to the outer circumference of the rotor core 1 (outermost outer peripheral portion) is directed from the outer peripheral end of the permanent magnet 3 toward the d-axis side. The rotor core 1 has a protruding portion 7 formed so as to extend substantially parallel to the outer circumference of the rotor core 1.

Since the outermost peripheral portion of the flux barrier 5B including the protruding portion 7 is formed substantially parallel to the outer peripheral portion of the rotor core 1, the magnetic flux density between the flux barrier 5B and the outer peripheral portion of the rotor 6 is uniformly saturated (magnetic saturation). , The magnetic flux that tends to flow in the q-axis direction is reduced.

As a result, the proportion of the magnetic flux flowing in the tip direction (d-axis direction) of the protruding portion 7 increases from the magnetic flux emitted from the permanent magnet 3B, and the rotor magnetic flux approaches a sine wave. The wave component (mainly 7th order) can be reduced. Similarly, since the flux barrier 11 also has a structure formed so as to extend substantially parallel to the outer periphery of the rotor core toward the d-axis side, it tends to flow toward the q-axis side like the flux barrier 5B. The magnetic flux is reduced, and the harmonic component of the magnetic flux density in the stator interlinkage magnetic flux can be reduced.

Next, a groove (rotor outer peripheral groove) 9 formed in the rotor core 1 of the present embodiment will be described.

During high-speed rotation when the rotary electric machine is operated as an electric machine, it is important to reduce the iron loss, which is dominant in the high-speed rotation range in the loss of the electric machine. In order to reduce the iron loss, it is effective to suppress the higher-order component of the magnetic flux interlinking from the rotor 6 to the stator 12. Therefore, in the rotor structure of the rotary electric machine of the present embodiment, iron loss is reduced by a characteristic configuration as described below.

As shown in FIG. 1, the rotor core 1 includes a groove 9 formed on the outer periphery of the rotor core 1 along the axial direction of the rotor core 1.

The groove 9 is formed in a shape that is concave from the outer peripheral surface of the rotor core 1 toward the center of the rotation axis in the cross-sectional view of the rotor core 1. The shape of the groove 9 is not necessarily limited to the U shape as shown in the figure, and may be formed in a V shape or the like.

The groove 9 is formed between the tangent line 1 and the tangent line 2 in the cross section of the rotor core 1 shown in FIG. The tangent line 1 is a line connecting the end on the q-axis side of the flux barrier 5A provided on the most q-axis side of the permanent magnet 3A in the first layer 50A and the rotation center point of the rotor core 1. The tangent line 2 is a line connecting the end on the d-axis side of the flux barrier 11 provided on the outermost peripheral side of the rotor core 1 and the rotation center point of the rotor core 1 among the magnetic barriers of the permanent magnet 3B of the second layer 50B. Is.

By forming the groove 9 at such a position, it is possible to suppress the higher-order component of the magnetic flux interlinking with the stator 12, and by smoothing the time change of the magnetic flux passing to the teeth of the stator 12, the stator The iron loss in 12 can be reduced.

Hereinafter, the flux barrier 5A provided on the most q-axis side of the permanent magnet 3A in the first layer 50A will be referred to as a "first flux barrier", and among the magnetic barriers related to the permanent magnet 3B in the second layer 50B, the rotor core. The flux barrier 11 (separated flux barrier 11) provided on the outermost peripheral side of No. 1 is also referred to as a “second flux barrier”.

FIG. 2 is an explanatory diagram showing the flow of magnetic flux of the rotor core 1 of the present embodiment.

In the rotor core 1, the direction of the magnetic flux generated from each permanent magnet 3 is regulated by the presence of the flux barriers 4, 5 and 11 which serve as magnetic resistances, as shown by the arrows in FIG.

In particular, in the rotor core 1, the region between the permanent magnet 3A of the first layer 50A and the permanent magnet 3B of the second layer 50B where no magnetic barrier exists (that is, between the tangent line 1 and the tangent line 2) is formed. The magnetic flux of each permanent magnet 3 passes as shown by the arrow. This magnetic flux interlinks with the stator 12 while spreading outward at the outer peripheral portion of the rotor core 1.

Therefore, as described above, by providing the groove 9 in the outer periphery of the rotor core 1 where the magnetic barrier does not exist (that is, between the tangent line 1 and the tangent line 2), the cross-sectional area of the rotor core 1 is slightly reduced. .. As a result, the higher-order component of the magnetic flux interlinking from the rotor 6 to the stator 12 can be suppressed, and the time change of the magnetic flux can be smoothed.

Next, the iron loss reduction effect due to the position of the groove 9 of the rotor core 1 of the present embodiment will be described with reference to the analysis results shown in FIG.

FIG. 3 is a diagram showing the relationship between the iron loss [W] of the present embodiment and the position angle [deg] at the center position of the groove 9.

FIG. 3 is an analysis result of the total iron loss [W] of the motor when the position angle [deg] of the groove 9 with respect to the d-axis is changed from 60 [deg] to 84 [deg]. The total iron loss without the groove 9 is shown as a horizontal solid line between 164 [W] and 165 [W].

When the position angle of the groove 9 is arranged between the tangent line 1 (near 66 [deg]) and the tangent line 2 (near 82 [deg]), the total iron loss is compared with the case where the groove 9 is not provided. Has been shown to be reduced.

As described above, the rotor structure of the first embodiment of the present invention includes a rotor core 1 of a rotor 6 having a plurality of magnetic poles provided in the circumferential direction, and a plurality of permanent magnets 3 constituting one magnetic pole in the rotor core 1. , Equipped with. One magnetic pole is composed of a first permanent magnet pair and a second permanent magnet pair, and the first permanent magnet pair is composed of a pair of permanent magnets 3A and 3A arranged so as to spread substantially V-shaped outward in the radial direction. The second permanent magnet pair is a pair of permanent magnets 3B and 3B arranged so as to spread substantially V-shaped outward in the radial direction on both outer sides of the permanent magnets 3A and 3A of the first permanent magnet pair in the circumferential direction. Consists of. A first flux barrier (flux barrier 5A) provided on the q-axis side that is electrically orthogonal to the d-axis formed by one magnetic pole in the first permanent magnet pair, and a d-axis formed by one magnetic pole in the second permanent magnet pair. A second flux barrier (end flux barrier 5B or separation flux barrier 11) provided on the q-axis side that is electrically orthogonal to the magnet is provided.

Then, the line connecting the q-axis side end of the first flux barrier and the rotation center point of the rotor core 1 is tangent 1, and the line connecting the d-axis side n end of the second flux barrier and the rotation center point of the rotor core 1 is defined as a tangent line 1. When the tangent line 2 is set, a groove (rotor outer peripheral groove) 9 formed along the axial direction of the rotor core 1 is formed on the outer periphery of the rotor core 1 between the tangent line 1 and the tangent line 2.

In the first embodiment of the present invention, by forming the groove 9 on the outer periphery of the rotor core 1 in this way, the higher-order component of the magnetic flux that comes out of each permanent magnet 3 and flows to the stator 12 is suppressed, so that the time of the magnetic flux The target change can be smoothed, and the iron loss of the electric motor can be reduced. That is, the groove 9 is formed on the outer circumference of the rotor core 1 at a position that suppresses a higher-order component of the magnetic flux of the magnet that comes out of each permanent magnet 3 and flows through the stator 12.

Further, the second flux barrier in the first embodiment of the present invention includes an end flux barrier 5B formed at the end of a second permanent magnet pair (permanent magnet 3B, 3B) and a second permanent magnet pair (permanent magnet). 3B, 3B) includes a separation flux barrier 11 formed near the end and away from the second permanent magnet pair (permanent magnets 3B, 3B), and the tangent line 2 is one of these flux barriers. This is a line connecting the end on the d-axis side of the flux barrier closest to the outer periphery of the rotor core 1 and the rotation center point of the rotor core 1.

As described above, in the second permanent magnet pair (permanent magnets 3B, 3B), the groove 9 is formed on the d-axis side of the magnetic barrier located on the outermost side of the rotor core 1, so that the groove 9 is formed on the outer peripheral side of the rotor core 1. Since the groove 9 acts to attenuate the high frequency component of the magnetic flux with respect to the magnetic flux interlinking with the stator 12 while spreading, the time change of the magnetic flux can be smoothed.

Further, in the first embodiment of the present invention, a second flux barrier (end flux barrier 5B) is provided at the end of each of the different magnetic poles adjacent in the circumferential direction on the q-axis side, and the different magnetic poles adjacent in the circumferential direction are provided. The rotor outer peripheral groove is not formed between the tangents 2 in the above.

With such a configuration, the cross-sectional area of the rotor core 1 is the outer periphery of the rotor core 1 where the magnetic flux of the first permanent magnet pair (permanent magnets 3A, 3A) and the magnetic flux of the second permanent magnet pair (permanent magnets 3B, 3B) flow. By slightly reducing the amount of magnetic flux, the change in magnetic flux over time can be smoothed and the iron loss of the electric motor can be reduced.

Further, in the second flux barrier (flux barrier 5B) of the present embodiment, the portion closest to the outer circumference of the rotor core 1 extends substantially parallel to the outer circumference of the rotor core 1 from the end of the permanent magnet 3B toward the d-axis. It has a protruding portion 7.

With such a configuration, the harmonic component of the magnetic flux density in the stator 12 is suppressed, and the iron loss can be reduced.

4 and 5 show a rotor structure of a modified example of the first embodiment of the present invention.

FIG. 4 shows a modified example in which the flux barrier 11 of the second layer 50B is open to the outer periphery of the rotor core 1 in the present embodiment.

Also in the modified example shown in FIG. 4, among the magnetic barriers of the magnetic flux of the permanent magnet 3B of the second layer 50B, the second flux barrier provided on the outermost peripheral side of the rotor core 1 is the flux barrier 11. Therefore, the tangent line 1 which is a line connecting the end of the first flux barrier (flux barrier 5A) on the q-axis side and the rotation center point of the rotor core 1 and the d-axis side of the second flux barrier (separated flux barrier 11) A groove 9 is arranged between the tangent line 2 which is a line connecting the end face of the rotor core 1 and the rotation center axis of the rotor core 1.

As a result, even if the flux barrier 11 is open to the outer periphery of the rotor core 1, the time change of the magnetic flux can be smoothed as described in FIGS. 1 and 2 described above, and the iron can be used. The loss can be reduced.

FIG. 5 shows a modified example in which the second layer 50B is not provided with the flux barrier 11 separated from the magnet hole 2B in the present embodiment.

In the modified example shown in FIG. 5, among the magnetic barriers of the magnetic flux of the permanent magnet 3B of the second layer 50B, the second flux barrier provided on the outermost peripheral side of the rotor core 1 is the end flux barrier 5B. Therefore, the tangent line 1 which is a line connecting the end of the first flux barrier (flux barrier 5A) on the q-axis side and the rotation center point of the rotor core 1 and the d-axis side of the second flux barrier (end flux barrier 5B) A groove 9 is arranged between the tangent line 2 which is a line connecting the end face of the rotor core 1 and the rotation center axis of the rotor core 1.

As a result, even when the separation flux barrier 11 separated from the magnet hole 2 is not provided, the time change of the magnetic flux can be smoothed as described in FIGS. 1 and 2 described above, and the iron can be used. The loss can be reduced. In particular, when the separation flux barrier 11 is not provided, the man-hours for manufacturing the rotor core 1 can be reduced as compared with the configuration provided with the separation flux barrier 11.

Next, the rotor structure of the second embodiment of the present invention will be described.

FIG. 6 is an explanatory diagram of a rotor structure according to a second embodiment of the present invention.

In the first embodiment described above, the position of the groove 9 is defined for the purpose of reducing iron loss. On the other hand, in the second embodiment, the position of the groove 9 is defined for the purpose of further reducing the torque ripple in addition to reducing the iron loss.

In the first layer 50A, the flux barrier 5A provided on the outer side in the radial direction of the permanent magnet 3A extends substantially parallel to the outer circumference of the rotor core 1. With this configuration, iron loss can be reduced by reducing the harmonic component of the magnetic flux density in the stator interlinkage magnetic flux, similarly to the protrusion 7 in the flux barrier 5B described above.

On the other hand, with such a configuration, the thickness of the bridge portion 8 formed between the flux barrier 5A and the outer periphery of the rotor 6 becomes thin in the radial direction. In such a configuration, when the motor rotates at high speed, the bridge portion 8 is deformed radially outward due to centrifugal force, which is arbitrary. When the rotor core 1 is deformed radially outward in the bridge portion 8, for example, the 96th-order torque ripple increases due to the fluctuation of the magnetic flux in this portion.

Therefore, in the second embodiment of the present invention, in order to suppress the radial deformation of the rotor core 1, the groove 9 is placed near the bridge portion 8, that is, at a position closer to the tangent line 1 than the tangent line 2. Formed. By arranging the groove 9 in the vicinity of the bridge portion 8, the bridge portion 8 can be deformed not in the radial direction but in the circumferential direction in which the groove 9 exists, and can be arbitrarily arranged. By configuring the bridge portion 8 to be deformed in the circumferential direction in this way, it is possible to suppress the deformation of the rotor core 1 in the bridge portion 8 in the radial direction.

FIG. 7 is a diagram showing the relationship between the torque ripple [Nm] and the position angle [deg] of the groove 9 with respect to the axis in the second embodiment of the present invention.

FIG. 7 is an analysis result of the torque ripple [Nm] generated when the position angle [deg] of the groove 9 with respect to the d-axis is changed from 60 [deg] to 84 [deg]. The torque ripple when the groove 9 is not provided is shown as a horizontal solid line near 4 [Nm].

Referring to FIG. 7, if the groove 9 is arranged between the tangent line 1 and the position where the groove 9 is advanced from the tangent line 1 in the rotation direction by 5 degrees (5 [degE]) in the electric angle, the groove 9 is formed. It has been shown that torque ripple is reduced by up to 33% compared to not having it.

As described above, in the second embodiment of the present invention, as shown in FIG. 6, a reference line shifted from the tangent line 1 in the q-axis direction by 5 degrees by the electric angle is set, and the groove 9 is set with the tangent line 1 and the reference line. Placed between and.

With such a configuration, in addition to the reduction of iron loss due to the groove 9 described in the first embodiment, the deformation of the rotor core 1 in the radial direction due to the rotation of the electric motor is suppressed, so that the deformation of the rotor core 1 occurs. Torque ripple can be reduced.

In the rotor structure according to the embodiment of the present invention described above, the number and shape of the grooves 9 are not particularly limited. Further, the number and arrangement of the permanent magnets 3 per magnetic pole in the rotor structure according to the present invention are not limited to the two V-shapes as described above. For example, a total of six permanent magnets 3 may be arranged with one magnetic pole as a three-layer structure.

The present invention is not limited to the above-described embodiments and modifications, and various modifications and applications are possible. For example, in the above description, the flux barriers 4, 5 and 11 have been described as void portions, but they do not necessarily have to be spaces. For example, the void portion may be filled with a non-magnetic material such as a resin material.

Further, in the above-described embodiment, regarding the relationship between the groove 9 and the tangent line 1, the tangent line 2, and the reference line, not all of the grooves 9 are between the tangent line 1 and the tangent line 2 (or between the tangent line 1 and the reference line). It doesn't have to be. That is, as shown in FIG. 8, the deepest portion h of the groove 9 may be between the tangent line 1 and the tangent line 2 (or between the tangent line 1 and the reference line), and a part of the groove 9 is the tangent line 1 and the tangent line. 2 and the reference line may be straddled.

Claims (6)

In a rotor structure of a rotary electric machine including a rotor core of a rotor having a plurality of magnetic poles provided in the circumferential direction and a plurality of permanent magnets constituting one magnetic pole in the rotor core.
The one magnetic pole is composed of a first permanent magnet pair and a second permanent magnet pair.
The first permanent magnet pair is composed of a pair of the permanent magnets arranged so as to spread outward in a radial direction in a substantially V shape.
The second permanent magnet pair is composed of a pair of the permanent magnets provided on both outer sides in the circumferential direction of the first permanent magnet pair and arranged so as to spread substantially V-shaped outward in the radial direction.
In the first permanent magnet pair, a first flux barrier provided on the q-axis side that is electrically orthogonal to the d-axis formed by the one magnetic pole,
In the second permanent magnet pair, a second flux barrier provided on the q-axis side that is electrically orthogonal to the d-axis formed by the one magnetic pole,
With
The line connecting the q-axis side end of the first flux barrier and the rotation center point of the rotor core is tangent 1, and the line connecting the d-axis side end of the second flux barrier and the rotation center point of the rotor core is defined as a tangent line 1. When it is tangent 2,
Between the tangent line 1 and the tangent line 2, a rotor outer peripheral groove formed along the axial direction of the rotor core is provided on the outer periphery of the rotor core.
Rotor structure of rotating electric machine. The rotor structure of the rotary electric machine according to claim 1.
The second flux barrier was separated from the end flux barrier formed at the end of the second permanent magnet pair in the vicinity of the end of the second permanent magnet pair and away from the second permanent magnet pair. Including, with a separation flux barrier formed at the position,
The tangent line 2 is a line connecting the end on the d-axis side of the flux barrier closest to the outer circumference of the rotor core and the rotation center point of the rotor core among the end flux barrier and the separation flux barrier.
Rotor structure of rotating electric machine. The rotor structure of the rotary electric machine according to claim 1 or 2.
The rotor outer peripheral groove is not formed between the tangents 2 at different magnetic poles adjacent to each other in the circumferential direction.
Rotor structure of rotating electric machine. The rotor structure of the rotary electric machine according to at least one of claims 1 to 3.
The second flux barrier has a protruding portion whose portion closest to the outer circumference of the rotor core extends substantially parallel to the outer circumference of the rotor core from the end of the permanent magnet of the second permanent magnet pair toward the d-axis. Have,
Rotor structure of rotating electric machine. The rotor structure of the rotary electric machine according to at least one of claims 1 to 4.
A stator having windings is provided on the outer circumference of the rotor.
The rotor outer peripheral groove is formed so as to suppress a higher-order component of the magnetic flux flowing from the permanent magnet to the stator.
Rotor structure of rotating electric machine. The rotor structure of the rotary electric machine according to at least one of claims 1 to 5.
The rotor outer peripheral groove is formed between a reference line in which the tangent line 1 is displaced by 5 degrees by an electric angle as the rotation center point of the rotor core in the q-axis direction and the tangent line 1.
Rotor structure of rotating electric machine.

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