Fuzzy Logic Based Power Quality Improvement Using Shuntactive Filter

This paper describes a novel fuzzy logic controller for a three phase shunt active shunt filter for the power quality improvement. The Power Quality (PQ) problems in power distribution systems are not new but only recently the effects of these problems have gained public awareness. These non-linear loads are constructed by nonlinear devices in which the current is not proportional to the applied voltage. For the harmonic elimination different methods are used, but in this paper a novel fuzzy logic controller for a three-phase shunt active power filter for the power quality improvement such as reactive power and harmonic current compensation generated due to nonlinear loads. The approach of fuzzy logic control is linguistic description, so it does not require a mathematical model of the system. The application of the fuzzy logic controller to a three phase shunt active power filter is investigated. The controller is capable of controlling dc capacitor voltage and generating reference source currents. And this controller provides current compensation, such that the compensated current drawn from the network is sinusoidal and balanced, corresponding to the fundamental positivesequence component of the load current, plus an additional fundamental positive sequence component to cover losses in the power circuit of the shunt active filter. The results are found to be quite satisfactory to mitigate harmonic Distortions, reactive power compensation and power quality improvement. Keywords— Non Linear Load, Power Quality, Shunt Active Filter, Series filter, Fuzzy Controller, harmonics, pi controller. ________________________________________________________________________________________________________