THD mitigation and power quality enhancement in a hybrid wind-PV system affected by grid imbalance and EV fast charging

Abstract The modernization of grid with inclusion of renewable energies and electric vehicle (EV) charging faces challenges due to the intermittent nature of renewable energies and the unpredictable load demand of EVs. This is expected to impose more severe impacts in next decades. A MATLAB Simulink model is designed for Hybrid Wind-Photovoltaic System (HWPVS) where wind energy conversion system is based on doubly-fed induction generator (DFIG). Photovoltaic (PV) rated at 2.8 MW is interconnected at DC link of rotor side converter (RSC) and grid side converter (GSC) of DFIG rated at 9 MW. A voltage unbalance of 0.5 pu is introduced in one phase at the generating end of 120 kv, 50 Hz. At the point of common coupling (PCC), DFIG and electric vehicle charging system (EVCS) consisting of 100 EVs are connected together. The grid imbalance and the EV charging effect, causing harmonics and deterioration in power quality are addressed by PI driven Adaptive Neuro Fuzzy Inference System (PI-ANFIS). The simulation results prove that the voltage and current profile is regulated and total harmonic distortion (THD) is suppressed at PCC, leading to sustainable and efficient power network. Also, PV support plays a crucial role in meeting the EV load demand.