Enhancement of Voltage Stability in Power System Using Unified Power Flow Controller

Voltage instability is one of the phenomenons that could happen in a power system due to stressed loading condition. The result would lead to the occurrence of voltage collapse which is nothing but the total blackout. Therefore voltage collapse possibilities and predictions are important in power system planning and operation so that the occurrence of voltage collapse due to voltage instability could be avoided. This paper presents a methodology of fast voltage stability index (FVSI) to identify the critical lines and buses to install the FACTS controllers. The line that gives FVSI value close to one will be taken as the most critical line corresponding to the bus, simulation results by using PSAT Software for the IEEE-14 bus system shows the location of UPFC in a particular line connected to the most critical bus to maintain the stability of the system.