Reduction of harmonics in 3-phase, 3-wire system by the use of shunt active filter

Harmonics are developed in transmission and distribution system with use of huge quantity of non-linear (transformer etc.,), power electronic equipments (bridge rectifier, power converters etc.,), in industrial and even house-hold electrical equipments. This will lead to damage either supply system or non-linear loads. In order to protect the supply system from current harmonics, we have to use the active power filters. These are used to compensate the reactive power compensation, but the performance of active power filters are based on various control strategies. This paper presents the complete examination to estimate the working of SHAF for generating the current references under steady and transient for balanced, unbalanced and non-sinusoidal conditions by using PI controller. The P-Q theory and synchronous reference frame theory, which are widely used in SHAF. The most validate results obtained by simulation with matlab/simulink software are carried out with PI controller for P-Q control theory for various voltage conditions like balanced, unbalanced and non-sinusoidal conditions and dynamic load changes.