Improved Loss Minimization Control for IPMSM Using Equivalent Conversion Method

Abstract

This article proposes an equivalent conversion-based improved loss minimization control method for interior permanent magnet synchronous motor (IPMSM). In the proposed control method, both the copper loss and iron loss are studied and the efficiency optimization problem due to the unequal inductance parameters of IPMSM is considered and solved, thus achieving the optimal efficiency. First, according to the mathematical model of the IPMSM considering iron loss resistance, the equivalent conversion method is presented to derive the relationship between electromagnetic torque, d-axis and q-axis currents. Then, by the polynomial fitting method, the d-axis and q-axis currents which minimize the electrical loss (copper loss and iron loss) are calculated. Additionally, to further show the performance of the proposed control method, the maximum torque per ampere control method and the approximate processing control method are studied for the comparative analysis. Both the simulation and experimental results show that the proposed control method can comprehensively reduce the electrical loss of the IPMSM, showing the effectiveness of the proposed control method.