1.1 Introduction
The Unified Power Flow Controller (UPFC) is a groundbreaking device in the realm of electrical power systems, designed to enhance the control and optimization of power flow across transmission lines. The Unified Power Flow Controller (UPFC) represents one of the most versatile and effective devices in the field of power system engineering. Introduced by Gyugyi in 1991, the UPFC integrates the functionalities of a shunt compensator (STATCOM) and a series compensator (SSSC) into a single device, allowing for simultaneous control of voltage, impedance, and phase angle in the transmission line. This capability significantly enhances the stability, reliability, and efficiency of power systems, making the UPFC a critical component in modern power flow management.
The UPFC operates through two voltage source converters (VSCs) that are connected back-to-back by a common DC link. One VSC is connected in shunt with the transmission line, while the other is connected in series. The shunt converter is responsible for injecting or absorbing reactive power to maintain the voltage at the connection point, whereas the series converter manages the power flow by injecting a voltage with controllable magnitude and phase angle. This dual functionality enables the UPFC to independently control the line impedance, voltage, and phase angle, thereby providing unparalleled flexibility in power flow management.
This chapter will address the background information that motivated this study, the challenges that prompted it, its aim, and its objectives as a preface to subsequent sections of the study. Additional factors include the study's significance, scope, limitations, and the definition of technical terms.
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