Power Quality Improvement using DSTATCOM with Fuzzy based Combined LMS–LMF-Based Control Algorithm

Abstract

In this paper Fuzzy based Combined LMS–LMF-Based Control Algorithm of DSTATCOM is presented. Power quality problems are of major concern in the distribution system that leads to decrease in efficiency of the system. The abundant uses of nonlinear loads inject harmonics into the system and decline the quality of power. Least mean square–least mean fourth (LMS–LMF)-based control algorithm is used for distribution static compensator (DSTATCOM) in three-phase distribution system to alleviate the power quality problems caused by solid-state equipments and devices. The proposed control algorithm has advantages of both LMF- and LMS-based control algorithms, which helps in fast and accurate response with a robust design. DSTATCOM is a shunt connected FACTS device. It is a reactive source that can be controlled and it is capable of absorbing or generating reactive power. DSTATCOM consists of coupling transformer, voltage source converter, DC energy storage device and necessary control circuits. In this paper fuzzy logic technique can be used to implement a controller for controlling the output of DSTATCOM. In order to maintain a constant voltage at the dc-bus of a voltage-source converter (VSC) and to obtain a fast dynamic response and for better performance proportional-integral (PI) controller is replaced with fuzzy logic controller is used. .In extension Fuzzy logic controller is used to reduce total harmonic distortion in the system and to attain better performance. The results are shown by using MATLAB/SIMULINK model.