New control strategy of unified power quality conditioner with sliding mode approach

This paper describes a novel sliding mode method with the fuzzy controller approach in the development of unified power quality conditioner (UPQC) for reactive power, harmonics and both symmetric and asymmetric sag and swell compensation. The UPQC consists of both shunt and series converter having a common dc link. The shunt converter eliminates current harmonics generated from the nonlinear load and the series converter suppresses the voltage sag and swell generated from the supply side. The dc link control strategy is based on fuzzy-logic controller where as sliding mode controller is used in the inner current control loop to dictate the gate signals for switching of the both converters. To determine the efficiency of UPQC model, it is implemented through MATLAB. The simulation results show the superior capability of the proposed approach in mitigating the effects of current harmonics and voltage sag and swell generated from the supply side.