Nonlinear predictive control for active power filter

A nonlinear optimal predictive controller for current control of paralleled three-phase three-leg active power filter is presented. The objective is to track distorted currents with sudden changes. In order to achieve robustness to parameter uncertainties, a disturbance observer is introduced. The deduced control law has closed analytical form and on-line dynamic optimization is omitted and easy to implement. The simulation results show that the APF based on the proposed control law has good performance, as well as strong robustness.