Permanent magnet linear synchronous motor with high air-gap flux density for transportation

Abstract

The characteristics of the high flux density linear synchronous motor (HFD-LSM) with the special field having V-letter array permanent magnets(PMs) are studied analytically by using a finite element method (FEM). For gap variation of plus or minus 4 mm to the typical gap 12 mm on the HFD-LSM with the thick PM of 40 mm, the change of thrust is only within 3% on the constant voltage drive. The change of efficiency is only within 0.5%. The efficiency considered only the copper loss exceeds 0.95 even in the case of the double length supply. The power factor is about 0.88 for maximum thrust drive. The influence of PM thickness appears remarkably on the power factor. For 10 mm thick PM, the reduction rate of the power factor is about 45% compared with 40 mm thick PM.