Current harmonics reduction using sliding mode control based shunt active power filter

Use of power electronic devices creates the power quality issues by generating harmonics and reactive power in the utility system. Active power filter is one of the best solution to reduce the harmonics level in the system. In this paper single phase shunt active filter using sliding mode control is implemented in MATLAB/Simulink. Sliding mode controller acts as a current controller to control filter inductor current by providing harmonics and reactive current required by the load. The switching signals to the shunt active power filter is generated based on the sliding surface and the source voltage. PI controller is used to control DC link voltage of active power filter along with generation of reference source current. Performance of proposed shunt active filter is analyzed under nonlinear and combined non-linear and linear load. It is observed that shunt active power filter improves the total harmonic distortion (THD) and power factor under variable load condition.