The rapid growth of electric vehicles (EVs) and renewable energy integration has significantly transformed modern power systems. Solar photovoltaic (PV) based EV charging infrastructure has emerged as an environmentally sustainable solution for transportation electrification. However, the integration of solar generation and EV charging loads introduces several power quality issues such as voltage fluctuations, harmonic distortion, reactive power imbalance, and load instability. These disturbances arise primarily due to the use of power electronic converters and the intermittent nature of solar energy generation. Poor power quality may lead to reduced efficiency of electrical equipment, overheating of devices, malfunction of protection systems, and instability in distribution networks. Therefore, improving power quality in solar-integrated EV charging stations is essential for ensuring reliable and efficient operation of the electrical grid. This research investigates the application of a Unified Power Quality Conditioner (UPQC) for mitigating power quality issues in solar-integrated EV charging systems. The UPQC is a custom power device consisting of series and shunt active power filters that operate simultaneously to compensate voltage and current disturbances. In the proposed system, a solar photovoltaic array is connected to a grid-integrated EV charging station through power electronic converters. The UPQC is installed at the point of common coupling (PCC) to regulate voltage variations, suppress current harmonics, and improve the power factor. The proposed model is implemented using simulation tools to analyze system performance under different operating conditions. Key parameters such as Total Harmonic Distortion (THD), voltage sag/swell, reactive power compensation, and load stability are evaluated. Simulation results demonstrate that the UPQC effectively reduces current harmonics, stabilizes voltage profiles, and improves overall system efficiency. The integration of UPQC also ensures compliance with power quality standards and enhances the reliability of solar-powered EV charging infrastructure. The findings of this study highlight the potential of UPQC-based compensation techniques in addressing the growing power quality challenges associated with renewable energy-based EV charging stations.
Roy et al. (Sat,) studied this question.