A Dual-Loop Model Predictive Power Control Scheme for Single-Phase PWM Rectifiers

This paper presents a dual-loop model predictive control (DMPC) direct power controller based on the idea of finite-control-set (FCS) predictive control for single-phase pulse width modulation (PWM) rectifiers. Compared with the traditional PI-based and CCS-MPC direct power control scheme, the proposed scheme adopts model predictive control for both power inner loop and voltage outer loop, which has a fast dynamic response. The complex tuning process of proportional integral parameters is eliminated, and a zero steady-state error control can be realized. Firstly, a two-axis stationary coordinate is established, and the discrete rectifier model is used to predict the active power, reactive power and DC voltage. Different switching vectors are calculated into the designed cost function to obtain the optimal switching vector, which is applied to the next control period. Meanwhile, an online inductance estimation scheme is adopted, which improves the robustness of the control system. MATLAB/Simulink simulation shows the proposed scheme can enhance the robustness of the system and improve dynamic response.