Analysis of Hysteresis Motor Based on Promoted General Airgap Field Modulation Theory

This paper presents a comprehensive investigation of the hysteresis motor (HM) based on the general airgap field modulation theory (GAFMT) promoted by vector magnetic circuit theory. The analysis focuses on capturing the three key effects that govern HM performance: the dominant hysteresis effect, eddy-current effect, and stator teeth effect. First, to capture the dominant hysteresis effect, a novel hysteretance modulator is proposed. Its modulation operator is formulated, and the corresponding modulation characteristics are thoroughly analyzed. The hysteresis angle between magnetic flux density (B) and magnetic field strength (H) is explicitly characterized using magnetic field parameters. A precise method for calculating the equivalent hysteretance is also developed to facilitate accurate performance prediction. Second, the eddy-current effect is modeled using the magductance modulator, allowing for analytical evaluation of the resulting torque contribution. Third, the influence of stator teeth on torque ripple is revisited using the salient pole reluctance (SPR) modulator. By incorporating all three torque-producing mechanisms within a unified modulation framework of GAFMT, this work establishes a comprehensive analytical model for HM performance. The proposed method is validated through comparison with results from finite element analysis (FEA) and experimental measurements.