IPMSM Control System Based on Maximum Torque Per Ampere Strategy

Based on the positive results of using PI type controllers in IPMSM (Internal Permanent Magnet Synchronous Motor) control systems, this paper presents the Maximum Torque Per Ampere (MTPA) control strategy, which achieves the maximisation of torque per ampere while maintaining and even improving control system performance when using the Field Oriented Control (FOC) control strategy. The paper presents the component control structures and the equations underlying the derivation of the i(d) and i(q) current references from the d-q axis reference frame representation to obtain a maximum torque per ampere. Numerical simulations for the control of an IPMSM using the two control strategies are presented and the superiority of the MTPA control strategy is concluded, expressed by the following performance indicators: response time, rotor speed ripple, maximum values and total harmonic distortion (THD) of the currents. The numerical simulations carried out in Matlab/Simulink also show a good robustness of the IPMSM control system when using the MTPA control strategy, maintaining the performance of the control system even when the nominal value of one of the IPMSM set-point parameters is doubled.