Frequency Response Comparison of PI-Based FOC and Cascade-Free MPC using 1 kHz SVM Applied to PMSM drive

Abstract— This paper presents a 1 kHz SVM-FOC (Space Vector Modulation with Field Oriented Control) drive system for a Permanent Magnet Synchronous Motor, using different control strategies. Such strategies are internal model and frequency response designed PI (Proportional and Integral) controllers and a multivariable MPC (Model Predictive Control) controller using a state-space prediction model. This MPC method becomes interesting for improving the closed-loop speed frequency response, since it results in a cascade-free controller. The performance of each controller was evaluated in a qualitative manner through simulations and quantitatively by load torque and speed reference AC sweeps, generating dynamic stiffness curves and Bode diagrams for the utilized techniques. Results show that the MPC approach is useful for enabling fast dynamic responses with the reduced switching frequency, which reduces the drive system cost and improves its efficiency.