Reactive Power Compensation and Harmonic Mitigation of Power Distribution Network Using Shunt Active Power Filter Based P-Q theory (Case study: Hawassa substation-2)

Abstract

Traditionally, the harmonic distortion and reactive power has been reduced using passive LC filters. However, the application of passive LC filters for reactive power compensation and harmonic mitigation results in parallel resonances with the network impedance. It is poor flexible for dynamic compensation of different frequency harmonic components.This work presented a scheme for reactive power compensation and harmonic mitigation of Hawassa substation-2 using shunt active power filter(SAPF), which is based on instantaneous p-q theory. The filter is identified, it automatically adapts to changes in the network and load fluctuations to mitigate the harmonics and reactive power issues. It is able to produce almost unity power factor and mitigate the total harmonics distortion (THD) to meet specified power quality standards. The performance of the SAPF depends mainly on the p-q theory to compute reference current and hysteresis band current controller to generate pulses for switching pattern of the inverter. The advantage of instantaneous p-q theory shows that it is instantaneous and works in time domain. MATLAB/Simulink computer simulation (version R2016a) is used as a simulation tool for this study. The simulation results before and after the compensation is compared to specified IEEE 519-1992 power quality standards.In three phase, three wire configurations, the result shows that THD in the load current is reduced from 37.46% to 3.56% and THD in the source voltage is reduced from 26.91% to 2.74% and power factor is improved from 0.869 to 0.949 under non ideal voltage source conditions while the reactive power is reduced from 1,178.04KVAr to 746.05KVAr