Minimum Loss Control Strategy of SPMSM Based on Curve Fitting

In order to realize the accurate setting of d-axis current reference under the efficiency optimization of surface permanent magnet synchronous motor (SPMSM), this paper proposes a loss minimum control (LMC) method based on curve-fitting. The method first analyzes the analytical expression of iron loss to the d-axis current under the mathematical model. Then, within the rated current range of SPMSM, iron loss can be approximately linear in the function of the d-axis current. Consequently, the solving process of the d-axis current reference is simplified to solve the quadratic equation. Furthermore, the d-axis current reference setting involves only the stator and iron loss resistances. Finally, the viability and efficacy of the proposed methodology are experimentally verified.