A Particle Swarm Optimization–Based Volt-VAR Control Strategy for Distribution System Incorporating Conservation Voltage Reduction

Abstract

The distribution network faces significant operational challenges in maintaining acceptable voltage levels under dynamic load conditions. Rapid load fluctuations often degrade the performance of localized voltage control schemes, leading to voltage instability and increased power losses. To address this issue, this paper proposes a centralized, optimization-based Volt-VAR control strategy that integrates Particle Swarm Optimization (PSO) with Conservation Voltage Reduction (CVR) for enhanced voltage regulation and energy efficiency in distribution systems. The proposed approach determines optimal tap positions of Automatic Voltage Regulators and On-Load Tap Changers using a system-wide optimization framework implemented in OpenDSS. A voltage-dependent load model is employed to realistically capture the impact of voltage variations on active and reactive power consumption. Simulation studies conducted on the IEEE-123 bus distribution system demonstrate that the PSO-based centralized control improves voltage regulation. It also reduces active power losses compared with conventional localized control. Additionally, peak load reduction is observed as a secondary benefit of CVR implementation. The proposed PSO-based control reduces active power losses from 4.72% to 4.59% and improves the minimum bus voltage from 0.8714 p.u. to 0.9459 p.u., ensuring voltage profiles remain within acceptable limits while enabling effective load reduction under CVR operation. The proposed framework provides a scalable and practical solution for advanced distribution management systems to improve voltage quality and energy efficiency.