Paper Title
Optimization-Based Control of Unified Power Flow Controller for Grid Stability

Abstract
The Unified Power Flow Controller (UPFC) plays a pivotal role in modern power systems, designed to enhance the controllability, flexibility, and efficiency of electrical power transmission. By leveraging advanced power electronic converters and intelligent control strategies, the UPFC enables real-time regulation of voltage magnitude, phase angle, and line impedance, allowing for optimal power flow management across transmission lines. This research focuses on the impact of UPFC on power quality and network stability, emphasizing its ability to mitigate voltage variations, reduce transmission losses, and improve dynamic system performance. Furthermore, the UPFC demonstrates high effectiveness in compensating disturbances such as voltage sags, swells, and flickers, thereby reinforcing the reliability and resilience of the power supply. comparative study isconducted on the performance of classical PIDand Fractional-Order PID (FO-PID) controllers applied to UPFC regulation foractive and reactive power control. Simulation results confirm that optimized UPFC control significantly enhances power flow stability, voltage profile, and overall power Keywords - FACTS, UPFC, PID Controller, Active power, Reactive power, FO-PID controllers