A Comprehensive PI controller design for PMSM field-oriented control incorporating vehicle dynamics

Abstract Permanent magnet synchronous motors (PMSMs) are widely used in electric vehicle (EV) applications due to their high efficiency and excellent torque characteristics. Field-oriented control (FOC) enables precise decoupled regulation of torque and flux in these systems, with proportional–integral (PI) controllers remaining the practical standard for current and speed loops. However, tuning these controllers is challenging because the closed-loop dynamics depend on the motor, inverter, and the vehicle’s dynamic load, which results in time-varying inertia and operating conditions. This paper presents a comprehensive PI controller design methodology for PMSM FOC that explicitly incorporates vehicle dynamics into the control framework. The approach accounts for inverter delay, sampling effects, and load-dependent inertia, enabling systematic gain selection for both current and speed loops. The tuned controllers are first evaluated through detailed simulations, including representative EV drive cycle, to assess tracking accuracy, transient response, and robustness. Experimental validation on a real-time controller platform further confirms the practical applicability of the proposed method. Simulation results show that the proposed approach achieves drivetrain efficiencies of 92.81% and 91.84% for the Japanese and combined urban and extra-urban driving cycle (CUEDC) respectively, compared with 59.89% and 85.05% obtained using conventional tuning without considering vehicle dynamics, corresponding to efficiency improvements of approximately 7.98% and 55.13%. These findings demonstrate that integrating vehicle dynamics into the PI tuning process significantly enhances efficiency, improves stability margins, and ensures consistent performance across a wide range of operating conditions.