Mitigation of Harmonics in 3-phase 3-wire System by using Fuzzy Logic Controlled Shunt Active Filter

Abstract

Most of the pollution issues created in power systems are due to the non-linear characteristics and fast switching of power electronic equipment. Due to this harmonics are produced and reactive power compensation is required, so that system efficiency is less and power factor is poor. Active power filters have been developed over the years to solve these problems to improve power quality. Among which shunt active power filter is used to eliminate and load current harmonics and reactive power compensation. The advantage of fuzzy control is that it provides linguistic values such as low, medium, high that are useful in case where the probability of the event to occur is needed. Advancement in semiconductor devices has fuelled an increase in the use of non-linear loads which are the main causes of harmonic distortion in three-phase, three-wire distribution systems. Mitigation of harmonics in three-phase, three-wire electrical power distribution systems that supply balanced and unbalanced non-linear loads was therefore conducted. In order to protect the supply system from current harmonics, we have to use the active power filters. Simulink model is developed for three phase three wire system under balanced source condition and three phase three wire system for unbalanced source condition. The performance of both balanced source and unbalanced source is done using Fuzzy Logic Controller and PI controller and their Simulink results is compared. Simulation results obtained shows that the performance of fuzzy controller is found to be better than PI controller.