Power Quality Improvement by Using Shunt Active Power Filter

Abstract

Presently, the large scale use of the power electronic equipment has led to an increase of harmonics in the power system. The harmonics reduces the power quality and have a negative economic impact on customers and utility. One of the major power quality issue is current harmonics. Active filter is the most feasible device which used to solve the power quality issues like harmonics and reactive power compensation. Shunt Active Filter (SHAF) is used to compensate the current harmonics. Effectiveness of the SHAF is depend on how rapidly and precisely its control strategy performed. Objective of this paper is to analyze the performance of SHAF with Proportional Integral (PI) and Fuzzy Logic Controller (FLC). To perform this analysis instantaneous active and reactive current technique is used to extract the reference current. In case of balanced supply voltage, both controllers give approximately same performance. However, FLC gives better performance than PI controller under unbalanced condition. Current harmonics are compensated by using these controllers and within the limit of IEEE Std. 519. MATLAB Simulation is carried out under balanced and unbalanced system voltage. Prototype hardware of SHAF is designed for three phase and results are discussed.