Enhancement of voltage stability and transmission congestion management with UPFC

Abstract

In the expanding transmission network, Congestion management and voltage stability are significant issues to be handled. Congestion management can be improved by increasing the power transfer capability or by reducing the system losses. With proper VAR support, the issue of voltage instability can be vanquished. Adaption of Flexible AC Transmission System (FACTS) devices is a techno-commercial manner to overcome the above issues. Unified Power Flow Controller (UPFC) is a pliable FACTS device which can control active power, reactive power and voltage injections concurrently in an efficient manner. In this paper power flow model of UPFC is described, location of UPFC is determined by Line Utilization Factor (LUF) and Line Voltage Stability Index (Lmn index) in order to find out the lines which are more vulnerable for congestion and voltage instability. The effectiveness of UPFC is tested on IEEE-14 bus system using MATLAB software. The results are compared with Placement and without placement of FACTS device.