volume | PIER Journals

Abstract

Fast, accurate modeling of permanent magnet synchronous machines (PMSMs) is essential for efficient design optimization, particularly in high-power wind turbine applications where severe magnetic saturation frequently occurs. While pure analytical models offer rapid computation, they often fail to accurately account for nonlinear saturation, which significantly affects the machine's performance, particularly the back-electromotive force (back-EMF). This study proposes a computationally efficient 2D hybrid analytical framework to investigate the impact of magnetic saturation on the back-EMF in PMSMs. The proposed approach couples an exact analytical subdomain (SD) technique, which is used to resolve the magnetic field in linear regions, with a nonlinear magnetic equivalent circuit (MEC) model for the active ferromagnetic parts. By iteratively updating the relative permeability in the MEC, the method accurately captured local saturation effects and reflected them in the global air-gap flux density. The developed hybrid analytical model (HAM) was used to analyze the total harmonic distortion (THD) and peak values of the back-EMF under saturated conditions. To validate the proposed method, results were compared with those obtained from a 2D finite element analysis (FEA). The comparison shows that the hybrid approach achieves an excellent compromise, delivering a high accuracy comparable to that of the FEA while drastically reducing computational time, making it highly suitable for iterative design and optimization process.

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Dr. Samir Mezghiche

Dr. Brahim Ladghem-Chikouche

Dr. Lazhar Roubache

Dr. Zakarya Djelloul-Khedda