PERFORMANCE ENHANCEMENT OF PMSG-BASED SMALL HYDRO POWER SYSTEMS USING BATTERY-SUPPORTED UPQC

Abstract

The growing penetration of renewable energy sources, power electronic interfaces, and nonlinear as well as unbalanced loads has significantly increased power quality (PQ) challenges in modern distribution systems. Addressing these PQ issues is essential to ensure reliable operation, improved efficiency, and reduced operational costs. This paper presents a unified power quality conditioner (UPQC) integrated with a standalone hydro-electric power generation system to simultaneously improve voltage and current quality. A permanent magnet synchronous generator (PMSG), driven by a hydro turbine, supplies power to sensitive local loads. A model predictive control (MPC) strategy is employed to generate optimal switching signals for the UPQC converters. The series compensator mitigates voltage disturbances and maintains load voltage at a constant rated magnitude with low harmonic distortion under varying operating conditions. Meanwhile, the shunt compensator ensures sinusoidal generator currents, supplies reactive power demand, and enforces unity power factor operation of the PMSG, thereby reducing system losses. In addition, a battery energy storage system supports stable operation during transient and load variations. The proposed system is validated through detailed MATLAB/Simulink simulations under multiple test conditions.