A stator, a permanent magnet brushless DC motor

Abstract

The present invention discloses a stator, which comprises a stator core. On the stator core, there is at least one set of A-phase, b-phase, C-phase, a-phase, B-phase, and c-phase arranged in sequence. Each phase includes at least two sets of pitches. The stator further includes element windings respectively arranged in the pitches, B-phase auxiliary windings, A-phase auxiliary windings, and C-phase auxiliary windings respectively wound on the A-phase, C-phase, and B-phase. The B-phase auxiliary winding has a winding direction opposite to that of the element winding in the adjacent b-phase, and is simultaneously wound on all sets of pitches in the A-phase. The A-phase auxiliary winding has a winding direction opposite to that of the element winding in the adjacent a-phase, and is simultaneously wound on all sets of pitches in the C-phase. The C-phase auxiliary winding has a winding direction opposite to that of the element winding in the adjacent c-phase, and is simultaneously wound on all sets of pitches in the B-phase. By arranging auxiliary windings on the stator, the cogging torque and torque ripple of the permanent magnet brushless DC motor having the stator can be reduced.

Description

Technical Field

[0001] The present invention relates to a stator and a permanent magnet brushless DC motor. Background Art

[0002] Existing permanent magnet brushless DC motors generally have a three-phase symmetrical design with equal number of turns. Due to the structural characteristics of the permanent magnets and the stator, the cogging torque is large and the torque ripple is large. In particular, it is difficult to start, which easily causes demagnetization or failure of the motor. The large torque ripple also makes it difficult to eliminate the running noise or resonance. Summary of the Invention

[0003] The object of the present invention is to provide a stator and a permanent magnet brushless DC motor having the stator, which can reduce the cogging torque and torque ripple of the permanent magnet brushless DC motor, effectively improve the excitation ability of the stator winding during the starting transient of the permanent magnet brushless DC motor, increase the slot-pole ratio, and eliminate the dead point of the permanent magnet brushless DC motor. During operation, the excitation area of the stator winding is increased, the motor power density is increased, and the motor efficiency is improved. At the same time, the auxiliary winding can also eliminate the harmonics of the permanent magnet brushless DC motor, reduce the torque ripple, reduce the noise of the permanent magnet brushless DC motor, and make the permanent magnet brushless DC motor operate efficiently, quietly and smoothly.

[0004] To achieve the above object, the technical solution adopted by the present invention is:

[0005] A stator includes a stator core, on which at least one set of A phase, b phase, C phase, a phase, B phase, and c phase arranged in sequence is provided. Each phase includes at least two sets of pitches. The stator further includes element windings respectively arranged in the pitches in a one-to-one correspondence, and B-phase auxiliary windings, A-phase auxiliary windings, and C-phase auxiliary windings respectively wound on the A phase, C phase, and B phase in a one-to-one correspondence;

[0006] The B-phase auxiliary winding has a winding direction opposite to that of the element winding in the adjacent b phase, and is simultaneously wound on all sets of the pitches in the A phase;

[0007] The A-phase auxiliary winding has a winding direction opposite to that of the element winding in the adjacent a phase, and is simultaneously wound on all sets of the pitches in the C phase;

[0008] The C-phase auxiliary winding has a winding direction opposite to that of the element winding in the adjacent c phase, and is simultaneously wound on all sets of the pitches in the B phase.

[0009] Preferably, in each set of the pitches of the A phase, b phase, C phase, a phase, B phase, and c phase, the number of turns of the element winding is the standard number of turns, and the standard number of turns is the number of turns in the equal number of turns design of a conventional permanent magnet brushless DC motor.

[0010] More preferably, the number of turns of the B-phase auxiliary winding, the A-phase auxiliary winding, and the C-phase auxiliary winding is all N, where N is between P / 4 and P / 2 of the standard number of turns, and P is the number of pole pairs.

[0011] A permanent magnet brushless DC motor includes the above stator.

[0012] Due to the application of the above technical solutions, the present invention has the following advantages compared with the prior art: A stator of the present invention and a permanent magnet brushless DC motor having the stator can reduce the cogging torque and torque ripple of the permanent magnet brushless DC motor by arranging auxiliary windings on the stator, and effectively improve the excitation ability of the stator winding during the starting transient of the permanent magnet brushless DC motor. The slot-pole ratio occupied is increased, the dead point of the permanent magnet brushless DC motor is eliminated, and the cogging torque is reduced. During operation, the excitation area of the stator winding is increased, the motor power density is increased, and the motor efficiency is improved. At the same time, the auxiliary winding can also eliminate the harmonics of the permanent magnet brushless DC motor, reduce the torque ripple, reduce the noise of the permanent magnet brushless DC motor, and make the permanent magnet brushless DC motor operate efficiently, quietly and stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Attached Figure 1 is a schematic structural diagram of the stator of the present invention.

[0014] Wherein: 1, element winding; 2, B-phase auxiliary winding; 3, A-phase auxiliary winding; 4, C-phase auxiliary winding. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] The technical solutions of the present invention will be further described below with reference to the drawings.

[0016] See Figure 1 As shown, the above stator includes a stator core, and at least one set of A-phase, b-phase, C-phase, a-phase, B-phase, and c-phase arranged in sequence is provided on the stator core. Each phase includes at least two pitches. In this embodiment, each phase includes two pitches.

[0017] The above stator further includes an element winding 1 provided in the pitch in one-to-one correspondence, a B-phase auxiliary winding 2 wound on the A-phase, an A-phase auxiliary winding 3 wound on the C-phase, and a C-phase auxiliary winding 4 wound on the B-phase. It can be seen from Figure 1 that the B-phase auxiliary winding 2 is adjacent to the b-phase, the A-phase auxiliary winding 3 is adjacent to the a-phase, and the C-phase auxiliary winding 4 is adjacent to the c-phase. And the B-phase auxiliary winding 2, the A-phase auxiliary winding 3, and the C-phase auxiliary winding 4 are arranged at intervals in sequence.

[0018] The above-mentioned auxiliary winding 2 of phase B has a winding direction opposite to that of the element winding 1 in the adjacent phase b, and is simultaneously wound on two pitch lengths in phase A. That is to say, the current direction in the auxiliary winding 2 of phase B is opposite to the current direction of the element winding 1 in phase b, and the generated magnetic fields are also opposite.

[0019] The above-mentioned auxiliary winding 3 of phase A has a winding direction opposite to that of the element winding 1 in the adjacent phase a, and is simultaneously wound on two pitch lengths in phase C. That is to say, the current direction in the auxiliary winding 3 of phase A is opposite to the current direction of the element winding 1 in phase a, and the generated magnetic fields are also opposite.

[0020] The above-mentioned auxiliary winding 4 of phase C has a winding direction opposite to that of the element winding 1 in the adjacent phase c, and is simultaneously wound on two pitch lengths in phase B. That is to say, the current direction in the auxiliary winding 4 of phase C is opposite to the current direction of the element winding 1 in phase c, and the generated magnetic fields are also opposite.

[0021] In each pitch length of phases A, b, C, a, B, and c, the number of turns of the element winding 1 is equal and is the standard number of turns. The standard number of turns is the number of turns in the equal-turn design of a conventional permanent magnet brushless DC motor.

[0022] The number of turns of the auxiliary winding 2 of phase B, the auxiliary winding 3 of phase A, and the auxiliary winding 4 of phase C are all equal and are N, where N is between P / 4 and P / 2 of the standard number of turns, and P is the number of pole pairs of the permanent magnet brushless DC motor.

[0023] A permanent magnet brushless DC motor including the above-mentioned stator can reduce the cogging torque and torque ripple of the permanent magnet brushless DC motor by setting auxiliary windings on the stator, and effectively improve the exciting ability of the stator winding during the starting transient of the permanent magnet brushless DC motor. The slot-pole ratio occupied is increased, the dead points of the permanent magnet brushless DC motor are eliminated, and the cogging torque is reduced. During operation, the exciting area of the stator winding is increased, the motor power density is increased, and the motor efficiency is improved. At the same time, the auxiliary winding can also eliminate the harmonics of the permanent magnet brushless DC motor, reduce the torque ripple, reduce the noise of the permanent magnet brushless DC motor, and make the permanent magnet brushless DC motor operate efficiently, quietly, and stably.

[0024] In this embodiment, the permanent magnet brushless DC motor is a 10-pole 12-slot motor, and the number of pole pairs is 5.

[0025] The above embodiments are only used to illustrate the technical concept and characteristics of the present invention. The purpose is to enable those familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A stator, comprising a stator core, on which there is at least one set of A-phase, b-phase, C-phase, a-phase, B-phase, and c-phase arranged in sequence, and each phase includes at least two sets of pitches. Characterized in that: The stator further includes element windings respectively arranged in the pitches in one-to-one correspondence, and B-phase auxiliary windings, A-phase auxiliary windings, and C-phase auxiliary windings respectively wound on the A-phase, C-phase, and B-phase. The B-phase auxiliary winding has a winding direction opposite to that of the element winding in the adjacent b-phase, and is simultaneously wound on all sets of the pitches in the A-phase. The A-phase auxiliary winding has a winding direction opposite to that of the element winding in the adjacent a-phase, and is simultaneously wound on all sets of the pitches in the C-phase. The C-phase auxiliary winding has a winding direction opposite to that of the element winding in the adjacent c-phase, and is simultaneously wound on all sets of the pitches in the B-phase. In each set of the pitches in the A-phase, b-phase, C-phase, a-phase, B-phase, and c-phase, the number of turns of the element winding is the standard number of turns, and the standard number of turns is the number of turns in the equal-turn design of a conventional permanent magnet brushless DC motor. The number of turns of the B-phase auxiliary winding, the A-phase auxiliary winding, and the C-phase auxiliary winding is N, and N is between P / 4 and P / 2 of the standard number of turns, where P is the number of pole pairs.

2. A permanent magnet brushless DC motor. Characterized in that: It includes the stator described in claim 1.

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