磁路互补型横向磁通切换直线电机电磁推力计算与特性分析

Owing to cogging effect, end effect and armature current harmonic, the high electromagnetic thrust ripple is inevitable in permanent magnet linear motor with an iron core, which directly influences the accuracy and smoothness of a linear machine in operating. This paper studies the electromagnetic thrust characteristics based on a flux-switching transverse flux permanent magnet linear motor with a complementary magnetic circuit. Firstly, the magnetic field distribution is analyzed by the equivalent magnetic road method, and the electromagnetic characteristics of the equal magnetic potential in the secondary of the motor are verified. Secondly, based on the air-gap magnetomotive force-permeability analysis method, the cogging thrust is suppressed under the complementary magnetic circuit condition, which realizes the non-cogging effect in the permanent magnet linear motor with the iron core. Then, the Schwarz-Christoffel transform model is proposed to analyze the electromagnetic thrust characteristics based on the air-gap magnetic felid distribution, and an analytical expression of electromagnetic thrust is derived. At last, experiments about no load-induced electromotive force and electromagnetic thrust are carried out to verify the proposed theoretical analysis model.