Techno-Economic Assessment of Voltage Stability Improvement Using SSSC and STATCOM in a Wind-Dominated Power System

The wind penetration level into the traditional existing transmission grid is posing new voltage stability challenges to Transmission System Operators. Wind power plants are required to meet the reactive power demands and the voltage control strategy. Shunt and Series FACTS devices are being used to increase the maximum transfer capability of a transmission line and the improvement of voltage stability. With the use of the aforementioned, voltage magnitudes, phase angles, and line impedances can be controlled. Worldwide, electric utilities use five popular types of FACTS devices for this purpose: STATCOM, SSSC, TCSC, SVC, and UPFC. For an electric utility, it would be practical if the voltage stability criterion is met using the most beneficial FACTS device. In this paper, the amelioration of the steady-state voltage stability of a wind-dominated power system using STATCOM and SSSC is compared in a modified IEEE-14 bus system. CCT amelioration with the use of SSSC is pointed out. Improvement of the loading margin of the weakest bus of the system is done by using STATCOM. Finally, some conclusions about the use of STATCOM and SSSC for voltage stability and power flow followed by the economic feasibility of the proposed solution are provided.