Simulation research on shunt active power filter with a novel control method

Three-phase three-line shunt Active Power Filter (APF) can be used to restrain harmonic current and compensate reactive power current on-line. The controller of APF is a core. Its performances play a key role in APF with excellent functions,and a control method is a critical point for designing the controller. Considering that APF is a coupling nonlinear system in synchronous rotating dq coordinate system,this paper proposes a novel control method:firstly the original system model of APF is linearized and decoupled to be a pseudo-linear system which is made up of original system and inverse system. Then it adopts Variable Structure Control Theory (VSC),and designs the variable structure control laws of this pseudo-linear system to control the system of APF. Finally,through establishing the system of APF and making simulations under the support of MATLAB soft,the excellent performances of APF to compensate harmonics and reactive power current have been verified sufficiently from the simulation results. The control method for APF presented in this paper is proved feasible and effective.