The rapid growth of renewable energy sources such as solar photovoltaic and wind power has significantly transformed modern electrical distribution networks. Although renewable energy integration offers environmental and economic advantages, it also introduces several operational challenges related to power quality. Variations in generation, intermittent output, and power electronic interfaces often cause voltage fluctuations, harmonic distortion, and reactive power imbalance in distribution systems. These issues can adversely affect system reliability, equipment performance, and overall grid stability. Therefore, advanced power conditioning techniques are required to maintain acceptable power quality levels in renewable energy integrated networks. This research investigates the application of a Unified Power Quality Conditioner (UPQC) for improving power quality in renewable energy integrated distribution systems. The UPQC combines series and shunt active power filters to mitigate voltage disturbances and current harmonics simultaneously. The proposed system integrates renewable energy sources with a distribution feeder and employs UPQC to regulate voltage, compensate reactive power, and reduce harmonic distortion. A detailed system model was developed and analyzed using a simulation platform to evaluate the effectiveness of the proposed approach. The study examines system behavior under different operating conditions including renewable generation variability and nonlinear load disturbances. Simulation results demonstrate that the UPQC significantly reduces harmonic distortion, stabilizes voltage profiles, and enhances overall power quality performance. The results confirm that the integration of UPQC in renewable energy distribution networks provides a reliable and efficient solution for mitigating power quality issues. The proposed approach contributes to improving the operational stability of renewable energy based power systems and supports the development of resilient smart grid infrastructures.
Mishra et al. (Thu,) studied this question.