Hybrid Method for Calculating AC Copper Loss in Permanent Magnet Linear Synchronous Motors

This paper proposes a method to determine AC copper losses in permanent-magnet linear synchronous motors (PMLSMs). For PMLSMs with finite-length cores and semi-closed slots, magnetic characteristics, particularly end effects, must be considered because structural differences in the end teeth cause flux-path saturation and variations in leakage flux, which strongly influence the proximity effect. Moreover, pulse-width-modulated (PWM) currents introduce high-frequency harmonics that significantly increase the AC copper loss. To enable accurate and efficient prediction of these losses, a hybrid approach that combines analytical equations formulated for round-wire windings with finite element analysis (FEA) is proposed. The effectiveness of this proposed method is demonstrated by comparison with transient FEA, showing high accuracy while substantially reducing computation time.