Three-phase Power Quality Device for Weak Systems Based on SRF and p-q theory Controller

This paper investigates on a three-phase Transformerless Hybrid Series Active Filter (THSeAF) to address major power quality issues related to residential and commercial buildings and presents an affordable solution to overcome current related issues as well as integrating renewables to ensure a sustainable supply. The controller based on a novel combination of Synchronous Reference Frame (SRF) and p-q theory to extract voltage and current harmonics and unbalances is developed in the paper. To produce gate switching signals for the three-phase THSeAF a conventional Proportional-Integral controller (PI) is used to produce reference waveforms produced earlier to rectify harmonic currents initiated from typical nonlinear loads. The device ensures a reliable and dynamically restored power supply on the load's point of common coupling (PCC) by means of three auxiliary DC supplies. This paper describes mitigation of power quality related issues into a micro grid system. Combination of simulation results and analysis arc carried out on a typical study case.