A novel nonlinear control stratege for single-phase APF based on feedback linearization

Currently active power filter control strategies are based on double-loop structure including current inner loop and voltage outer loop. A unified control method based on exact feedback linearization is presented for single-phase active power filter in this paper. First, the output function which contains compensation current and DC side voltage variables is obtained by solving the partial differential equation. Then, in order to transferring the nonlinear system into diffeomorphisms second order linear system, the nonlinear state feedback control law is derived. Third, the controller which forces the output function asymptotically track the reference output is designed by selecting appropriate feedback coefficients. So it is come true that unified controlling of compensation current and DC side voltage. Finally, the correctness and feasibility of proposed control method is verified by simulation and experiment.