Shunt active power filter based on a novel sliding mode backstepping control for three-phase three-wire system

Abstract

This paper presents a global fast terminal sliding mode (GFTSM) control based on back stepping design for active power filter(APF). Power system is a typical nonlinear system. Its mathematic model can be reduced order by back stepping method. Power system is decomposed into low-level subsystems until finalizing the design of the control law. The System's stability is ensured by Lyapunov framework. The sliding mode control is added into back stepping control to expand the application scope of control. The sliding mode control doesn't need accurate model of system. Therefore robustness of APF control is improved. Global fast terminal control is added into sliding mode control. The nonlinear term of GFTSM control makes the system converge quickly when far from equilibrium point, and the linear term do when near equilibrium point. It makes the system's state tracking error reach zero in finite time. The control speed of system is enhanced. An experiment based on MATLAB/SIMULlNK is designed to compare GFTSM backstepping control with pure back stepping control, and experimental results confirm the validity of proposed APF controller for a three-phase three-wire system .