Research on Air Gap Magnetic Field Characteristics of Trapezoidal Halbach Permanent Magnet Linear Synchronous Motor Based on Improved Equivalent Surface Current Method

Accurate analysis of the air gap magnetic field is focus research in precision permanent magnet linear synchronous motors. In this paper, two-dimensional a secondary trapezoidal Halbach array coreless motor (PMLSM) was taken as our object. On basis equivalent surface current method, we proposed an improved analytical algorithm with side length unit. The model induction vector established, and PMLSM calculated. At same time, analyzed influence bottom angle ? width coefficient ?w, pole height ?h, ?g on amplitude (Bpeak) total harmonic distortion (THDB) central gap. results show that ?w have significant Bpeak THDB With synergy identified “flux convergence” effect, which makes maximum range > 90° < 0.5. We also found “equilateral” causes minimum region to change linearly. calculation established paper agree those verified by finite element method. convenient, accuracy result high. This provides new method for analyzing nonrectangular cross-section lays theoretical foundation optimizing model.