Multi-Objective Optimization Simulation of Unified Power Quality Conditioner (UPQC)

Abstract

This research paper proposes a multi-objective optimization approach for enhancing power system stability using a Unified Power Quality Conditioner (UPQC). The UPQC parameters and control strategies are optimized under various operating conditions and constraints using Pareto optimality and particle swarm optimization techniques. MATLAB/Simulink simulations confirm the effectiveness of the proposed method in improving power quality and stability. The results demonstrate a substantial reduction in voltage total harmonic distortion at the point of common coupling, tight regulation of load voltage within acceptable limits, significant power factor correction, and an optimized VA rating of the UPQC device, while satisfying all optimization constraints. Sensitivity analysis reveals the UPQC performance is most sensitive to source impedance and DC link voltage variations. The proposed multi-objective optimization framework provides a systematic approach for optimal planning and operation of UPQC systems in power distribution networks. It enables finding the best tradeoffs among conflicting objectives such as voltage distortion, voltage regulation, power factor, and equipment rating. The optimization procedure is carried out for different scenarios including distorted grid conditions and VA rating limitations. This study underscores the importance of optimizing UPQC design and control, considering multiple criteria, to maximize power quality improvement and voltage stability in modern distribution grids with increasing penetration of nonlinear loads and distributed generation.