三相异步起动永磁同步电动机起动特性

针对永磁电机牵入同步困难的问题，依据永磁电机基本原理和电磁场理论，对异步起动永磁同步电动机的起动性能进行了研究。以一台18．5kW6极切向式三相异步起动永磁同步电动机为例，建立永磁电动机起动过程的数学模型，给出了求解域和假定条件下的有限元方程，采用场路结合法计算了异步起动永磁同步电动机的瞬态电磁场，分析了样机的起动过程及隔磁磁桥尺寸变化和绕组排列不同对电机起动性能的影响。通过样机对模型仿真分析可知，样机具有较好的起动性能，能快速牵入同步转速，采用单双层绕组时起动性能要比采用双层绕组时的起动性能好；隔磁磁桥尺寸对电机的起动性能影响很大，其过大或过小都会使起动性能变差，不利于牵入同步转速。

Analysis of starting characteristics of three-phase line-start permanent magnet synchronous motor

As to the fact that it is difficult to arrive at the synchronous speed for permanent-magnet synchronous motors(PMSM),the starting characteristics of a line-start PMSM are studied based on the permanent-magnet electrical machine basic principle and the electromagnetic field theory in this paper.A mathematical model on starting process of a 3-phase tangential-field PMSM of 18.5 kW and 6 poles is developed.The finite element equations under assumptions as well as the solving region of the derived model are presented.Then the transient electromagnetic field of line-start permanent-magnet synchronous motor is calculated by the coupled field-circuits method;and the effect due to the variation of flux barrier of rare-earth size and type of winding-distribution on starting performance of the motor is analyzed.Finally the simulation of the prototype motor is given,and the analysis of the simulation illuminates that the starting performance of the prototype motor is so preferable that the prototype motor can arrive at the synchronous speed quickly.The starting performance of the motor with single-layer and double-layer windings is better than that with double-layer windings.The size of flux barrier of rare-earth has a severe influence on the starting performance of the motor,viz.larger or smaller size making difficulty of arriving at the synchronous speed of the motor.