Comparison of Integration of Phase Shift Transformer (PST) and Flexible Alternative Current Transmission System (FACTS) Devices in the Power System Network. Case Study Rwanda Power Transmission Network

This study presents the comparison of the integration of PST, UPFC, and STATCOM in Rwanda's transmission line for reactive power compensation. The study utilized MATLAB/SIMULINK (2013a) to model Rwanda's 110kV north hub transmission line. The design without compensation showed the voltage magnitude of buses at 0. 8 Per unit voltage; with PST, STATCOM, and UPFC per unit voltage varying between 0.988 to 0.997,0.9 to 1.1, and 0.9 to 1.2 respectively. The findings of real and reactive power showed that the real power of the model with PST and STATCOM was reduced at all buses as its operation caused real power losses. The real power of UPFC increased on all buses, UPFC can adjust the transmission of power flow and decrease the real power losses. The result of this study after comparison indicated that UPFC performs better and controls the real and reactive power more than PST and STATCOM.