Synchronous reluctance motor rotor structure and synchronous reluctance motor

Abstract

The invention discloses a synchronous reluctance motor rotor structure and a synchronous reluctance motor. The rotor structure comprises a rotating shaft and a rotor core installed on the rotating shaft. The rotor core is provided with a plurality of air magnetic barrier groups which are circumferentially distributed, the air magnetic barrier groups protrude towards the radial inner side of the rotor core, each air magnetic barrier group comprises a plurality of air magnetic barrier layers which are arranged in the q-axis direction, and a magnetic conductive layer is formed between every two adjacent air magnetic barrier layers; the cross section of each air magnetic barrier layer along the radial direction of the rotor is considered to be enclosed by two long boundary lines and two short boundary lines, and the two long boundary lines are respectively an inner side long boundary line and an outer side long boundary line which meet a circular curve parameter equation; two end points and two short boundary lines of the long boundary line of the air magnetic barrier layer meet other parameter equations; in the same air magnetic barrier group, the long boundary lines of different magnetic barrier layers adopt different circle centers to form an eccentric circle magnetic barrier. By combining the asymmetrically-designed eccentric circle magnetic barriers, the output torque of the synchronous reluctance motor can be improved, and the torque pulsation can be reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of synchronous reluctance motors, and in particular relates to a synchronous reluctance motor rotor structure and a synchronous reluctance motor. Background Art

[0002] In the context of energy conservation and emission reduction, synchronous reluctance motors have gained wide attention due to their simple structure, wide speed regulation range, and low cost. Compared with permanent magnet synchronous motors, synchronous reluctance motors do not have permanent magnets, so there is no need to consider the risk of permanent magnet demagnetization at high temperatures. Compared with induction motors, synchronous reluctance motors eliminate the need for squirrel cage bars and excitation windings on the rotor, reducing losses on the rotor and saving motor manufacturing costs. However, synchronous reluctance motors also have some problems, such as large torque pulsation and low output torque, which hinder the application of synchronous reluctance motors.

[0003] The synchronous reluctance motor uses the principle of minimum reluctance to generate reluctance torque, and the magnitude of the reluctance torque is related to the d-axis and q-axis inductance values. The larger the difference between the d-axis inductance and the q-axis inductance, the greater the reluctance torque of the synchronous reluctance motor; the smaller the difference between the d-axis inductance and the q-axis inductance, the smaller the reluctance torque of the synchronous reluctance motor. The shape of the magnetic barrier of the synchronous reluctance motor affects the difference in inductance between the d-axis and q-axis. In order to increase the difference in inductance, the shape of the magnetic barrier of the synchronous reluctance motor needs to be optimized.

[0004] The large torque pulsation of the synchronous reluctance motor is mainly related to the existence of spatial harmonics in the synchronous reluctance motor, and the spatial harmonics are mainly caused by the unreasonable design of the stator and rotor geometric structures and the stator current distortion. Generally, the stator structure and winding distribution of the synchronous reluctance motor are the same as those of the three-phase asynchronous motor of the same capacity. Therefore, the large torque pulsation of the synchronous reluctance motor is mainly due to the unreasonable design of the rotor geometric structure.

[0005] At present, the problems of large torque pulsation and low output torque of synchronous reluctance motors are mainly solved by optimizing the design of rotor structure. To this end, the present application proposes a synchronous reluctance motor rotor structure and a synchronous reluctance motor. Summary of the invention

[0006] In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a synchronous reluctance motor rotor structure and a synchronous reluctance motor.

[0007] The technical solution adopted by the present invention to solve the technical problem is as follows:

[0008] A synchronous reluctance motor rotor structure comprises a rotating shaft and a rotor core mounted on the rotating shaft; a plurality of air magnetic barrier groups distributed in a circumferential manner are arranged on the rotor core, the air magnetic barrier groups protrude toward the radial inner side of the rotor core, each air magnetic barrier group comprises a plurality of air magnetic barrier layers arranged along the q-axis direction, and a magnetic conductive layer is formed between adjacent air magnetic barrier layers; the characteristic is that a cross section of each air magnetic barrier layer along the radial direction of the rotor is regarded as being surrounded by two long boundary lines and two short boundary lines, the two long boundary lines are inner and outer long boundary lines respectively, and both satisfy the circular curve parameter equations of formulas (1) to (6);

[0009]

[0010]

[0011] P B P D 2 +O′P D 2 = r′ 2 (3)

[0012] P A P D +O′P D = r′ (4)

[0013]

[0014]

[0015] Among them, P A is the intersection of the line connecting the centers O and O′ and the circle with O′ as the center, P B , P C is the intersection of the circles centered at O ​​and O′, P D P B With P C The midpoint of the connecting line, r is the radius of the circle with O as the center, and r' is the radius of the circle with O' as the center;

[0016] The two end points P of the long boundary line of the air magnetic barrier layer B , P C And any point of the two short boundary lines satisfies the parametric equation of formula (7);

[0017]

[0018] Among them, (x, y) is the position coordinate of the point, and δ is the angle between the perpendicular line from the point to the central axis of the rotor and the d-axis.

[0019] Each long boundary line of the air magnetic barrier corresponds to a circle center O'; the magnetic barrier opening angle θ, the magnetic barrier layer center thickness h and the magnetic barrier end width w are determined according to the O' position, r and r'.

[0020] Furthermore, each air magnetic barrier group includes three air magnetic barriers; in the same air magnetic barrier group, an eccentric circular air magnetic barrier formed when the centers are not equal is used; the distances between the centers O′ corresponding to the long boundary lines of adjacent air magnetic barrier groups and the coordinate origin O are equal; the angle parameters corresponding to the centers O′ of the long boundary lines in the same air magnetic barrier group are equal; in the four air magnetic barrier groups, the magnetic barrier opening angle θ, the center thickness h of the magnetic barrier layer and the width w of the end of the magnetic barrier are equal, the centers O′ of the long boundary lines of the two air magnetic barrier groups on the upper left and lower right sides are maintained on the q axis, and the centers O′ of the long boundary lines of the two air magnetic barrier groups on the upper right and lower left sides are offset about the q axis The ratio of the center thickness of the first and second air magnetic barrier layers is 0.5-4, and the ratio of the center thickness of the second and third air magnetic barrier layers is 0.5-3; the ratio of the opening angle of the first and second air magnetic barrier layers is 1.1-1.5, and the ratio of the opening angle of the second and third air magnetic barrier layers is 1.1-2; the ratio of the end width of the first and second air magnetic barrier is 0.5-2, and the ratio of the end width of the second and third air magnetic barrier is 0.5-2; the offset angle of the air magnetic barrier group is It is -3°~3°.

[0021] Furthermore, when the ratio of the center thickness of the first and second air magnetic barrier layers is 2.61, the ratio of the center thickness of the second and third air magnetic barrier layers is 0.91; the ratio of the opening angle of the first and second air magnetic barrier layers is 1.31, the ratio of the opening angle of the second and third air magnetic barrier layers is 1.73; the ratio of the end width of the first and second air magnetic barrier layers is 1.05, the ratio of the end width of the second and third air magnetic barrier layers is 0.95; the offset angle of the air magnetic barrier group When the angle is -2.45°, the rotor structure improves the output torque of the synchronous reluctance motor and reduces torque pulsation.

[0022] The present invention further provides a synchronous reluctance motor, characterized in that the synchronous reluctance motor comprises the rotor structure described in any one of claims 1 to 3.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The long boundary line of the air magnetic barrier layer of the rotor structure is composed of circular arc lines, wherein each circular arc corresponds to a circle center separately, and a concentric circular air magnetic barrier and an eccentric circular air magnetic barrier can be formed; relative to the rotor structure of the concentric circular air magnetic barrier, the freedom of the rotor structure of the present invention is improved, and the center thickness of the air magnetic barrier layer, the magnetic barrier opening angle and the width of the magnetic barrier end can be adjusted separately by changing the center position and radius of the circle; by changing the angle between the circle center corresponding to the long boundary line and the q-axis, an asymmetric rotor structure can be formed, which can further reduce the torque pulsation of the synchronous reluctance motor; compared with the rotor structure of the concentric circular air magnetic barrier, the rotor structure of the present invention is helpful to improve the output torque of the synchronous reluctance motor and reduce the torque pulsation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the rotor structure of the present invention;

[0026] Figure 2 Schematic diagram for rotor air magnetic barrier boundary formation;

[0027] Figure 3 This is a schematic diagram of the rotor air magnetic barrier offset;

[0028] Figure 4 is a torque curve diagram of the synchronous reluctance motor of the present invention;

[0029] Figure 5 It is a torque harmonic analysis diagram of the synchronous reluctance motor of the present invention;

[0030] In the figure, 1-the first air magnetic barrier layer; 2-the second air magnetic barrier layer; 3-the third air magnetic barrier layer; 4-the first magnetic conductive layer; 5-the second magnetic conductive layer; 6-the rib; 7-the rotating shaft; 8-the rotor core. DETAILED DESCRIPTION

[0031] The technical solution of the present invention is clearly and completely described below in conjunction with the accompanying drawings, but the protection scope of the present application is not limited thereto.

[0032] like Figure 1 As shown, the present invention provides a synchronous reluctance motor rotor structure, including a rotating shaft 7 and a rotor core 8 installed on the rotating shaft 7; a plurality of air magnetic barrier groups distributed in a circumferential manner are provided on the rotor core 8, the air magnetic barrier groups protrude toward the radial inner side of the rotor core, each air magnetic barrier group includes a plurality of air magnetic barrier layers arranged along the q-axis (the q-axis refers to the center line of the air magnetic barrier group itself), and a magnetic conductive layer is formed between adjacent air magnetic barrier layers; in this embodiment, each air magnetic barrier group is provided with three air magnetic barrier layers, and the air magnetic barrier groups are, from the inside to the outside, the first air magnetic barrier layer 1, the first magnetic conductive layer 4, the second air magnetic barrier layer 2, the second magnetic conductive layer 5, and the third air magnetic barrier layer 3; the portion between the end of each air magnetic barrier layer and the edge of the rotor core 8 is a rib 6, and the rib width is 1 mm in this embodiment.

[0033] like Figure 2 As shown, the cross section of each air magnetic barrier layer along the radial direction of the rotor is considered to be composed of two long boundary lines and two short boundary lines. The two long boundary lines are the inner and outer long boundary lines, respectively, and both satisfy the circular curve parameter equations of equations (1) to (6);

[0034]

[0035]

[0036] P B P D 2 +O′P D 2 = r′ 2 (3)

[0037] P A P D +O′P D = r′ (4)

[0038]

[0039]

[0040] Among them, P A is the intersection of OO′ and the circle with O′ as the center, P B , P C is the intersection of the circles centered at O ​​and O′, P D P B With P C The midpoint of the connecting line, r is the radius of the circle with O as the center, and r' is the radius of the circle with O' as the center;

[0041] The two end points P of the long boundary line of the air magnetic barrier layer B , P C And any point of the two short boundary lines satisfies the parametric equation of formula (7);

[0042]

[0043] Among them, (x, y) is the position coordinate of the point, and δ is the angle between the perpendicular line from the point to the central axis of the rotor and the d-axis.

[0044] like Figure 3As shown, each long boundary line of the air magnetic barrier corresponds to a circle center O′. When the circle centers are at the same position, a concentric air magnetic barrier is formed, and when the circle centers are not equal, an eccentric air magnetic barrier is formed. The barrier opening angle θ, the barrier layer center thickness h and the barrier end width w are determined according to the position of O′, r and r′. In the same air magnetic barrier group, when the circle center O′ corresponding to any long boundary line is not located on the q-axis, a rotor structure asymmetric about the q-axis is formed. In adjacent air magnetic barrier groups, when the angle between the circle center O′ corresponding to any long boundary line and the d-axis is unequal, a rotor structure asymmetric about the d-axis is formed.

[0045] Each air magnetic barrier group includes 3 air magnetic barriers; the rotor structure is asymmetric about the d-axis and the q-axis; in the same air magnetic barrier group, an eccentric circular air magnetic barrier formed when the centers are not equal is used; the distances between the centers O′ corresponding to the long boundary lines of adjacent air magnetic barrier groups and the coordinate origin O are equal; the angle parameters corresponding to the centers O′ of the long boundary lines in the same air magnetic barrier group are equal: in the 4 air magnetic barrier groups, the magnetic barrier opening angle θ, the center thickness h of the magnetic barrier layer and the width w of the end of the magnetic barrier are equal, the centers O′ of the long boundary lines of the two air magnetic barrier groups on the left are maintained on the q-axis, and the centers O′ of the long boundary lines of the two air magnetic barrier groups on the right are offset about the q-axis The two air magnetic barrier groups on the right are symmetrical about the d axis; the ratio of the center thickness of the first and second air magnetic barrier layers is 0.5-4, and the ratio of the center thickness of the second and third air magnetic barrier layers is 0.5-3; the ratio of the opening angles of the first and second air magnetic barrier layers is 1.1-1.5, and the ratio of the opening angles of the second and third air magnetic barrier layers is 1.1-2; the ratio of the end widths of the first and second air magnetic barriers is 0.5-2, and the ratio of the end widths of the second and third air magnetic barriers is 0.5-2; the offset angle of the air magnetic barrier group is It is -3°~3°.

[0046] Example

[0047] The main parameters of the synchronous reluctance motor of this embodiment are shown in Table 1.

[0048] Table 1 Main parameters of the motor

[0049]

[0050] When the ratio of the center thickness of the first and second air magnetic barrier layers is 2.61, the ratio of the center thickness of the second and third air magnetic barrier layers is 0.91; the ratio of the opening angle of the first and second air magnetic barrier layers is 1.31, the ratio of the opening angle of the second and third air magnetic barrier layers is 1.73; the ratio of the end width of the first and second air magnetic barrier is 1.05, the ratio of the end width of the second and third air magnetic barrier is 0.95; the offset angle of the air magnetic barrier group When the angle is -2.45°, the rotor structure improves the output torque of the synchronous reluctance motor and reduces torque pulsation.

[0051] Figure 4 This is a torque comparison diagram of the synchronous reluctance motor of the present invention and the synchronous reluctance motor with concentric air magnetic barriers after optimization using a multi-objective algorithm; the average torque of the synchronous reluctance motor of the present invention is 71.32, and the torque pulsation is 4.75%; the average torque of the synchronous reluctance motor with concentric air magnetic barriers is 71.72, and the torque pulsation is 8.17%; relative to the synchronous reluctance motor with concentric air magnetic barriers, the torque pulsation of the synchronous reluctance motor of the present invention is reduced by 41.86% without substantially losing output torque.

[0052] Figure 5 It is a torque harmonic analysis diagram of the synchronous reluctance motor of the present invention and the synchronous reluctance motor with concentric air magnetic barrier after optimization by a multi-objective algorithm; the 6th to 42nd high-order harmonics of the synchronous reluctance motor of the present invention are reduced by 25.31%, 67.26%, 24.43%, 71.70%, 43.06% and 87.44% respectively compared with the synchronous reluctance motor with concentric air magnetic barrier.

[0053] In summary, the simulation results show that the synchronous reluctance motor of the present invention has higher output torque and lower torque ripple than the synchronous reluctance motor with concentric air magnetic barriers.

[0054] Any matters not described in the present invention are applicable to the prior art.

Claims

1. A synchronous reluctance motor rotor structure, comprising a rotating shaft and a rotor core mounted on the rotating shaft; a plurality of air magnetic barrier groups distributed in a circumferential manner are arranged on the rotor core, the air magnetic barrier groups protrude radially inwardly of the rotor core, each air magnetic barrier group comprises a plurality of air magnetic barrier layers arranged along the q-axis direction, and a magnetic conductive layer is formed between adjacent air magnetic barrier layers; characterized in that: The cross section of each air magnetic barrier layer along the rotor radial direction is considered to be enclosed by two long boundary lines and two short boundary lines; the two long boundary lines are the inner and outer long boundary lines respectively, and both satisfy the circular curve parameter equations of equations (1) to (6); P B P D 2 +O′P D 2 =r′ 2 (3) P A P D +O'P D =r′ (4) Among them, P A is the intersection of OO′ and the circle with O′ as the center, P B , P C is the intersection of the circles centered at O ​​and O′, P D P B With P C The midpoint of the connecting line, r is the radius of the circle with O as the center, and r' is the radius of the circle with O' as the center; The two end points P of the long boundary line of the air magnetic barrier layer B , P C And any point of the two short boundary lines satisfies the parametric equation of formula (7); Where (x, y) is the position coordinate of the point, and δ is the angle between the perpendicular line from the point to the rotor center axis and the d-axis; Each long boundary line of the air magnetic barrier corresponds to a circle center O'; the magnetic barrier opening angle θ, the magnetic barrier layer center thickness h and the magnetic barrier end width w are determined according to the O' position, r and r'.

2. The synchronous reluctance motor rotor structure according to claim 1, characterized in that: Each air magnetic barrier group includes 3 air magnetic barriers; the distances between the centers O′ corresponding to the long boundary lines of adjacent air magnetic barrier groups and the coordinate origin O are equal; the angle parameters corresponding to the centers O′ of the long boundary lines in the same air magnetic barrier group are equal; in the 4 air magnetic barrier groups, the magnetic barrier opening angle θ, the center thickness h of the magnetic barrier layer and the width w of the magnetic barrier end are equal, and the centers O′ of the long boundary lines of the two air magnetic barrier groups on the upper left and lower right sides are maintained on the q axis, and the centers O′ of the long boundary lines of the two air magnetic barrier groups on the lower left and upper right sides are offset about the q axis.

3. The synchronous reluctance motor rotor structure according to claim 2, characterized in that: The ratio of the center thickness of the first and second air magnetic barrier layers is 0.5-4, and the ratio of the center thickness of the second and third air magnetic barrier layers is 0.5-3; the ratio of the opening angle of the first and second air magnetic barrier layers is 1.1-1.5, and the ratio of the opening angle of the second and third air magnetic barrier layers is 1.1-2; the ratio of the end width of the first and second air magnetic barrier is 0.5-2, and the ratio of the end width of the second and third air magnetic barrier is 0.5-2; the offset angle of the air magnetic barrier group is It is -3°~3°.

4. The synchronous reluctance motor rotor structure according to claim 3, characterized in that: When the ratio of the center thickness of the first and second air magnetic barrier layers is 2.61, the ratio of the center thickness of the second and third air magnetic barrier layers is 0.91; the ratio of the opening angle of the first and second air magnetic barrier layers is 1.31, the ratio of the opening angle of the second and third air magnetic barrier layers is 1.73; the ratio of the end width of the first and second air magnetic barrier is 1.05, the ratio of the end width of the second and third air magnetic barrier is 0.95; the offset angle of the air magnetic barrier group When the angle is -2.45°, the rotor structure improves the output torque of the synchronous reluctance motor and reduces torque pulsation.

5. A synchronous reluctance motor, characterized in that: The motor comprises the rotor structure described in any one of claims 1-4.

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