Three-phase doubly salient motor with non-uniformly distributed stator pole widths

Abstract

The invention discloses a three-phase doubly salient motor with non-uniform stator pole width distribution. The three-phase doubly salient motor comprises a stator iron core, a rotor iron core, an excitation element, an armature winding and a rotating shaft, and is characterized in that the rotor iron core is arranged inside the stator iron core, the rotating shaft is arranged inside the rotor iron core, the excitation element is arranged at the yoke part of the stator iron core, the armature winding is wound on the stator pole of the stator iron core, a rotor pole is arranged on the rotor iron core, the pole width of the stator pole is unevenly distributed, the pole width of the rotor pole is evenly distributed, the maximum pole width dmax of the stator pole is equal to the pole width of the rotor pole, the minimum pole width dmin is two thirds of the pole width of the rotor pole, the rotor iron core and the stator iron core are both of a salient pole structure, the number of the rotor poles is 4N, the pole-arc coefficient of the rotor is 0.5, the number of the stator poles is 6N, and N is a positive integer. According to the invention, approximate sine of the induction electromotive force of the armature winding of the doubly salient motor is realized, so that the doubly salient motor can adopt sine wave power supply, the torque ripple of the doubly salient motor is reduced, and the iron core loss of the motor is reduced.

Description

technical field [0001] The invention relates to a three-phase double-salient pole motor with uneven distribution of stator pole width, which belongs to the field of motor design. Background technique [0002] Doubly salient motors are divided into electric excitation doubly salient motors, permanent magnet doubly salient motors and hybrid excitation doubly salient motors. Because there is no winding on the rotor, the structure is simple, the reliability is high, and it has the advantages of high power density. With extensive attention and research by scholars at home and abroad, its design and control technology is becoming more and more mature, and it has good application prospects in wind power, aviation and automobile industries. [0003] As a kind of reluctance motor, doubly salient motor has the inherent defect of large torque ripple, which has become the biggest obstacle to its application in the field of high-performance drive and servo; the working mode of the tradit...

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Problems solved by technology

[0003] As a kind of reluctance motor, doubly salient motor has the inherent defect of large torque ripple, which has become the biggest obstacle to its application in the field of high-performance drive and servo; the working mode of the traditional structure of electrically excited doubly salient motor is similar to Brushless DC motor, but its back EMF is not an ideal square wave. The motor adopts a square wave current control method. Due to the current commutation in the peak area of ​​the motor winding inductance, the large inductance causes the current commutation time to become longer, making the motor commutation torque Visible pulsation

[0004] In order to reduce the torque ripple of the doubly salient motor, Professor Zhu Ziqiang from the University of Sheffield in the United Kingdom conducted research on the variable reluctance motor and proposed a 6 / 7 pole doubly salient motor, which makes the back EMF of the motor basically tend to be sinusoidal, which can be The output torque ripple is greatly reduced, and the sinusoidal drive of the reluctance motor is realized; however, the excitation elements of the motor are distributed across a single stator pole, so the number of excitation elements increases significantly, the excitation loss increases, and the number of motor rotor poles is an odd number , it is easy to generate asymmetric vibration during operation, so it is usually necessary to at least double the number of rotor poles. However, a high number of poles also requires a higher switching frequency of the converter; in order to reduce torque ripple and increase the degree of sinusoidalization of the motor, Usually, the rotor of a three-phase double salient pole motor can be designed as a chute structure, or a segmented rotor structure, but the chute structure or rotor segmentation will affect the mechanical strength of the rotor, especially not suitable for high-speed applications

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