A Study on Voltage Stability Improvement using STATCOM and UPFC

Voltage stability is one of the most important criteria that is needed to be considered in the transmission lines so that it could provide a reliable electrical energy to the users. The occurrence of voltage instability is mostly cause by high demand of electrical energy and the power system is unable to meet certain reactive power demands alongside with the difficulties of the system to keep up the desired or demanded voltages. Flexible AC Transmission Lines or known as FACTS devices are one of the best methods to improve voltage stability in the transmission lines by controlling some related parameters. This paper focus on improving the voltage stability in the IEEE-14 bus Static Synchronous Compensator (STATCOM) and Unified Power Flow Controller (UPFC) besides determine the most effective locations for the placement of FACTS in the IEEE-14 bus by analysing the voltage stability of bus 4 and bus 14 during pre-fault, fault, and post-fault condition. The simulation is performed using PSAT toolbox in the MATLAB software. To conclude, Static Synchronous Compensator (STATCOM) and Unified Power Flow Controller (UPFC) improve the voltage instability of IEEE-14 bus by controlling the voltage and phase angle and deliver constant reactive power to the system.