Modeling and Control of Three-Phase Shunt Active Power Filter using P-Q Theory for Power Quality Improvement

Voltage, current and frequency are the three physical characteristics that define the power quality and power quality issue can be stated as “any occurrence manifested in current, voltage or frequency deviations that results in damage, upset or failure of end-use equipment’s�. The higher switching frequency and the non-linear properties of the power electronics devices are responsible for harmonics in the system and create power quality issue. So importance is being given to the development of Active Power Filters to solve harmonic problems and to improve power quality by reactive power compensation. This paper presents mathematical modeling and analysis of Shunt Active Power Filter which is implied to eliminate source voltage, load current harmonics and for reactive power compensation. The shunt active power filter is developed based on control strategy i.e. instantaneous active and reactive power theory (p-q theory) is used to generate the reference current for the filter controller is proposed. Shunt active filter makes the source current sinusoidal by eliminating current harmonics under balanced and unbalanced load conditions. Hysteresis current controller is implemented to generate the gating signals for IGBT’s in voltage source inverter. Shunt Active Power Filter (SAPF) is simulated and results are investigated through MATLAB/Simulink.