Improved Active Power Filter for Renewable Power Generation Systems

Abstract

The performance analysis of four-leg voltage-source inverter using a Fuzzy logic control scheme is presented. The use of a four-leg voltage-source inverter allows the reduction of current harmonic components, as well as unbalanced and Negative sequence currents generated by single-phase nonlinear loads. The compensation performance of the proposed active power filter and the associated control scheme under steady state and transient operating conditions is demonstrated through simulations results. In recent times, fuzzy logic controller was applied for active power filter (APF) control application, as the APF is nothing but a current controlled VSI. In this paper, a fuzzy logic based shunt APF is presented based on the effective time concept. The effective time concept eliminates the trigonometric calculations and sector identification, thereby it reduces the computational effort. Simulation results demonstrate the efficacy of the APF with the fuzzy logic based control strategy. Simulation results are obtained for both PI controller and fuzzy logic controller and the results are compared. In the fuzzy controlled four leg inverter APF is used for power quality improvement.