Robust Adaptive Variable Structure Controller for Shunt Active Power Filters

This paper proposes and analyzes a current control technique applied to the current control of a three-phase shunt Active Power Filter. The technique is based on an adaptive variable structure controller. The adaptive algorithm compensates for the parametric uncertainties and a modification is applied for robustness with respect to the unmodeled dynamics. The variable structure action built in the adaptive controller improves the stability and dynamic performance if compared with a conventional adaptive controller. Theoretical discussions and experimental results are presented to better support the paper.