An Advanced SVPWM-Based Predictive Current Controller for Three-Phase Inverters in Distributed Generation Systems

Space vector pulsewidth modulation (SVPWM) has been widely applied in the current control of three-phase voltage source inverters (VSIs). However, for grid-connected VSIs in distributed generation (DG) systems, the performance of current controllers based on SVPWM is compromised by the grid harmonics and the control delay due to computation and sampling. In this paper, an advanced SVPWM-based predictive current controller is proposed and studied. The controller mimics deadbeat control in the synchronous d-q reference frame, and is very simple and robust to implement. With the necessary grid voltage detection in DG systems for protection, grid harmonics disturbance is effectively suppressed through feedforward compensation. Based on a dual-timer sampling scheme, the control delay compensation becomes more simple yet effective. The comprehensive analysis on the proposed predictive current control system is provided. The simulation and experimental test results show that the proposed current controller has an excellent steady-state response as well as an extremely fast dynamic response.