Investigation of Shunt Active Power Filter for Power Quality Improvement in Distribution System

In distribution systems, the load has been a unexpected increase or decreases and it is like as nonlinear loads so the load draw non-sinusoidal currents from the utility mains and causes the reactive power load, harmonics and high neutral currents that occurs the power quality problem in electrical distribution systems. Most power quality problem created in distribution systems are due to the nonlinear load and fast switching of power electronic devices. Shunt active filter based on current controlled PWM converters are seen as a most viable solution. In this paper, a shunt active power filter (SAPF) with PI controller is used. Current controlled voltage source converter topology is used in this SAPF. The quality and performance of SAPF depend on design of power converter, DC voltage control strategy, the method implemented to generate reference command and generation of switching pulses. For reference command generation Unit Active Power Component Theory (APCT) is used and for DC voltage control PI controller is used. A hysteresis current controller is used to generate the switching pulses. The detailed simulation study of work has been carried out in MATLAB/Simulink environment. Keywords—Power Quality, SAPF, Distribution System, APCT