Performance Comparison of PI, PR, and FCS-MPC Controllers for Three-Phase VSIs

With the increasing demand for efficient and robust control strategies in power electronics applications, this work analyses and compares four strategies for controlling the output voltage of a three-phase Voltage Source Inverter (VSI) used to supply various types of loads. The study evaluates two linear controllers, Proportional Integral (PI) and Proportional Resonant (PR) and two Finite Control Set Model Predictive Controllers (FCS-MPC), a classic FCS-MPC with variable switching frequency to a modulated version ensuring constant frequency. Notably, the load current is estimated without integrating the load model into the FCS-MPC equations, with performance assessed through extensive simulations. Several tests compare the controllers’ steady-state and transient performance under various conditions, including different load types, distorted currents, and parameter changes. FCS-MPC controllers respond faster but are more affected by parameter variations, while linear controllers offer better accuracy, lower errors, and greater robustness to changes. These insights contribute to optimizing controller design for applications demanding speed, robustness, and power quality.