Assessment of Voltage Unbalance and Power Losses in Distribution Network Integrated With PVs and EV Charging Stations

ABSTRACT Unequal load distribution in three‐phase power distribution networks leads to voltage unbalance and decreased network efficiency. Integration of photovoltaics (PVs) and electric vehicle charging stations (EVCSs) into such networks is a challenging task as their penetration affects the power quality of the system. Considering the varying load demand and PV generation alongside the stochastic nature of electric vehicles (EVs), this study presents a technique for the precise placement of the PV system and EVCS inside the unbalanced networks to enhance the performance of the system. The optimal placement of PVs and EVCSs is carried out by considering real Pakistani 60‐bus unbalanced radial distribution systems (URDS), whereas to minimize the voltage unbalanced factor (VUF) and active power loss (APL), a metaheuristic technique, improved grey wolf optimization (IGWO) was used. Six different case studies of the integration of PVs and EVCSs inside the system are considered in this work. The simulation results demonstrate that the integration of the single‐phase PVs and EVCSs resulted in an increase of APL by 18.04% and VUF by 21.78%. However, the APL and VUF decreased by 14.82% and 3.96%, respectively, for the three‐phase integration of the same size of PVs and EVCSs. Hence, the integration of three‐phase PVs and EVCSs enhanced the system performance in comparison to the single‐phase integration.