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CN-115987044-B - Harmonic distortion suppression type permanent magnet motor based on split stator permanent magnet

CN115987044BCN 115987044 BCN115987044 BCN 115987044BCN-115987044-B

Abstract

The invention discloses a harmonic distortion suppression type permanent magnet motor based on split stator permanent magnet excitation, which comprises a stator, a split stator permanent magnet excitation structure, a rotor laminated by silicon steel sheets, an armature winding and a non-magnetic-conductive rotating shaft, wherein the stator and the rotor respectively adopt split permanent magnets and salient pole structures, two permanent magnets magnetized outwards in radial direction and two permanent magnets magnetized inwards in radial direction are always arranged in the split stator permanent magnets on stator teeth and are opposite to a rotor salient pole when the rotor rotates to form a main magnetic circuit path in the motor, and air gaps between the four permanent magnets and the rotor salient pole form four magnetic resistances, and the four magnetic resistances, the permanent magnets and a stator iron core together form a differential magnetic circuit structure, so that disturbance of higher harmonic waves in an air gap magnetic field to harmonic distribution can be reduced, harmonic distortion in the air gap magnetic field can be effectively suppressed, torque output capacity can be improved, and torque pulsation can be reduced. The invention has the advantages of large output torque, low torque pulsation and high efficiency.

Inventors

  • WANG HAITAO
  • WANG XIN
  • DING SHUYE

Assignees

  • 南京师范大学

Dates

Publication Date
20260505
Application Date
20221202

Claims (10)

  1. 1. The harmonic distortion suppression type permanent magnet motor based on split stator permanent magnet excitation is characterized by comprising a rotor (1) and a stator (2), wherein the rotor (1) and the stator (2) are coaxially sleeved; The rotor (1) comprises a non-magnetic rotating shaft (101), a rotor yoke (102) and a plurality of rotor salient poles (103), wherein the non-magnetic rotating shaft (101) and the rotor yoke (102) are coaxially sleeved, the rotor yoke (102) and the plurality of rotor salient poles (103) are integrally formed, and the plurality of rotor salient poles (103) are uniformly arranged on the surface of an annular inner ring of the rotor yoke (102) according to the circumferential direction; The stator (2) comprises a plurality of stator teeth (201), a stator yoke (202), a plurality of split stator permanent magnets (203), a plurality of armature windings (204) and a plurality of stator grooves (206), wherein the plurality of stator teeth (201) are uniformly arranged on the annular inner ring surface of the stator yoke (202) along the circumferential direction, the plurality of stator teeth (201) and the stator yoke (202) are integrally formed, the plurality of split stator permanent magnets (203) are arranged on the arc inner ring surface of the stator teeth (201), the stator grooves (206) are cavities formed between adjacent stator teeth (201), the armature windings (204) are wound on the stator teeth (201) and are arranged in the stator grooves (206), and an air gap is reserved between the plurality of split stator permanent magnets (203) and the plurality of rotor salient poles (103); The position relation between the rotor salient poles (103) and the split stator permanent magnets (203) is met, when the rotor (1) rotates, four split stator permanent magnets (203) are respectively opposite to the four rotor salient poles (103), at the moment, four magnetic resistances are formed between the four split stator permanent magnets (203) and the air gaps by the four rotor salient poles (103) which are respectively opposite to the four split stator permanent magnets, and the four magnetic resistances, the split stator permanent magnets (203), the rotor yoke (102), the rotor salient poles (103), the stator teeth (201) and the stator yoke (202) form a differential magnetic circuit structure together so as to reduce disturbance of higher space harmonic waves in an air gap magnetic field to harmonic distribution.
  2. 2. A permanent magnet machine with harmonic distortion suppression based on split stator permanent magnet excitation according to claim 1, wherein, The split type stator permanent magnets (203) comprise a plurality of split type stator permanent magnets (203) magnetized outwards in the radial direction and a plurality of split type stator permanent magnets (203) magnetized inwards in the radial direction, and the pole arc coefficients of the split type stator permanent magnets (203) are equal.
  3. 3. A permanent magnet machine with harmonic distortion suppression based on split stator permanent magnet excitation according to claim 2, wherein, The number of split stator permanent magnets (203) provided on the arcuate inner ring surface of each of the stator teeth (201) is an integer multiple of four.
  4. 4. A permanent magnet machine with harmonic distortion suppression based on split stator permanent magnet excitation according to claim 3, characterized in that, Four split stator permanent magnets (203) are arranged on the surface of the arc-shaped inner ring of each stator tooth (201).
  5. 5. A permanent magnet machine with harmonic distortion suppression based on split stator permanent magnet excitation according to claim 4, wherein, The number Z r of the rotor salient poles (103), the pole pair number P PM of the split stator permanent magnet (203) and the pole pair number P a of the space armature magnetic field generated when the three-phase sinusoidal alternating current is injected into the armature winding (204) satisfy the following formula P a ＝p PM -Z r .
  6. 6. A permanent magnet machine with harmonic distortion suppression based on split stator permanent magnet excitation according to claim 5, wherein, The two ends of the arc-shaped inner ring of each stator tooth (201) are respectively provided with one split-type stator permanent magnet (203), two sides of the central axis of each stator tooth (201) are respectively provided with one split-type stator permanent magnet (203) at intervals, the distances between the two split-type stator permanent magnets (203) on the middle of the arc-shaped inner ring of each stator tooth (201) and the central axis of each stator tooth (201) are equal, the intervals between the two split-type stator permanent magnets (203) on the two sides of the central axis of each stator tooth (201) are equal, and in the whole, the adjacent split-type stator permanent magnets (203) are opposite.
  7. 7. A permanent magnet machine with harmonic distortion suppression based on split stator permanent magnet excitation according to claim 5, wherein, Also comprises a plurality of direct current excitation windings (205); The two ends of the arc-shaped inner ring of each stator tooth (201) are respectively provided with a split type stator permanent magnet (203), and the two sides of the central axis of each stator tooth (201) are respectively provided with a split type stator permanent magnet (203) at intervals; The polarities of the two split stator permanent magnets (203) which are close to the central axis of the stator teeth (201) are the same, and the polarities of the two split stator permanent magnets (203) which are positioned on the same side of the central axis of the stator teeth (201) are opposite; every two split stator permanent magnets (203) located on the same side of the central axis of the stator teeth (201) And one direct current excitation winding (205) is arranged between the two windings.
  8. 8. A permanent magnet machine with harmonic distortion suppression based on split stator permanent magnet excitation according to claim 5, wherein, The split number of the stator teeth (201) is 2, namely, each stator tooth (201) is provided with two split stator teeth (207) which are respectively positioned at two sides of the central axis of the stator tooth (201), two split stator permanent magnets (203) with opposite polarities are arranged on the arc-shaped inner ring of each split stator tooth (207), and the polarities of the adjacent split stator permanent magnets (203) are opposite as a whole.
  9. 9. A permanent magnet machine with harmonic distortion suppression based on split stator permanent magnet excitation according to claim 5, wherein, The number of splits of the stator teeth (201) is 4, namely four split stator teeth (207) are arranged on each stator tooth (201), one split stator permanent magnet (203) is arranged on an arc-shaped inner ring of each split stator tooth (207), and polarities of adjacent split stator permanent magnets (203) are opposite.
  10. 10. A permanent magnet machine with harmonic distortion suppression based on split stator permanent magnet excitation according to claim 5, wherein, The split number of the stator teeth (201) is 4, namely four split stator teeth (207) are arranged on each stator tooth (201), one split stator permanent magnet (203) is arranged on an arc-shaped inner ring of each split stator tooth (207), the polarities of the two split stator permanent magnets (203) in the middle on each stator tooth (201) are the same, and the polarities of the two split stator permanent magnets are opposite to those of the split stator permanent magnets (203) at the two ends respectively, and the polarities of the adjacent split stator permanent magnets (203) at the two ends are the same between the adjacent stator teeth (201); A pair of direct current excitation windings (205) are arranged between the two split stator permanent magnets (203) with opposite polarities, wherein the direct current excitation winding (401) which is close to the non-magnetic rotating shaft (101) and is the permanent magnet S pole is arranged, and the direct current excitation winding (402) which is far away from the non-magnetic rotating shaft (101) and is the permanent magnet N pole is arranged.

Description

Harmonic distortion suppression type permanent magnet motor based on split stator permanent magnet Technical Field The invention relates to the field of motor design, in particular to a harmonic distortion suppression type permanent magnet motor based on split stator permanent magnets. Background With the development of the motor industry, the permanent magnet motor has a great deal of application in the industrial and traffic fields due to the advantages of high efficiency, high power density, high reliability and the like. Permanent magnet machines are often classified into rotor permanent magnet machines and stator permanent magnet machines according to the permanent magnet position, with the rotor permanent magnet machines developing earlier and more mature. In recent decades, with the continuous development of permanent magnet materials and power electronics, stator permanent magnet motors have been widely focused and studied by researchers because of their high reliability and high torque density. The stator permanent magnet motor is excited by the permanent magnet, has no copper loss of the exciting armature winding, has relatively higher efficiency, is suitable for high-speed operation and high-temperature working conditions, has no friction noise and electric spark problems caused by the exciting armature winding, has higher reliability, and has light rotor mass, small moment of inertia and faster acceleration and deceleration response. The stator armature windings are mostly concentrated armature windings, the processing and the manufacturing are convenient, the electromagnetic isolation of the concentrated armature windings is good, the fault tolerance performance is good, the armature winding coefficient is smaller, the inductance is smaller, and the electrical time constant is shorter. However, the traditional stator permanent magnet motor has high harmonic content of an air gap field, so that the torque pulsation is large, noise vibration is caused by the torque pulsation, and positioning errors occur. Therefore, the harmonic distortion of the air gap field of the stator permanent magnet motor is restrained, and the reduction of the torque pulsation of the stator permanent magnet motor becomes a research hot spot in the field of stator permanent magnet motors. In recent years, scholars at home and abroad have made a great deal of research about the suppression of air gap harmonic distortion of a stator permanent magnet motor. The Lin Mingyao teaching of southeast university suggests that the rotor asymmetric teeth can effectively improve the air gap structure, but the structure of the asymmetric teeth is easy to cause rotor eccentricity, the Kitai teaching of Hanyang university suggests a permanent magnet chamfering method to inhibit air gap harmonic distortion, however, the permanent magnet chamfering can cause permanent magnet forming difficulty, and the Li Taobo teaching of Shandong university suggests a rotor tooth surface optimization method to reduce the breath harmonic content. The method can effectively inhibit harmonic distortion, but optimizes the stator permanent magnet motor from the angle of motor structural parameter change, which easily leads to the structural complexity of the motor, and the method faces great challenges both from the aspect of manufacturing process and mass production of finished products. Disclosure of Invention Aiming at the problems, the invention provides a harmonic distortion suppression type permanent magnet motor based on a split stator permanent magnet. In order to achieve the aim of the invention, the invention provides a harmonic distortion suppression type permanent magnet motor based on split stator permanent magnet, which comprises a rotor and a stator, wherein the rotor and the stator are coaxially sleeved; the rotor comprises a non-magnetic rotating shaft, a rotor yoke and a plurality of rotor salient poles, wherein the non-magnetic rotating shaft and the rotor yoke are coaxially sleeved, the rotor yoke and the plurality of rotor salient poles are integrally formed, and the plurality of rotor salient poles are uniformly arranged on the surface of an annular inner ring of the rotor yoke according to the circumferential direction; The stator comprises a plurality of stator teeth, a stator yoke, a plurality of split type stator permanent magnets, a plurality of armature windings and a plurality of stator grooves, wherein the plurality of stator teeth are uniformly arranged on the surface of an annular inner ring of the stator yoke along the circumferential direction, the plurality of stator teeth and the stator yoke are integrally formed, the plurality of split type stator permanent magnets are arranged on the surface of an arc-shaped inner ring of the stator teeth, the stator grooves are cavities formed between adjacent stator teeth, the armature windings are wound on the stator teeth and are arranged in the stator grooves, and air gaps are reserv