Determination of the power transfer capacity of a UPFC with consideration of the system and equipment constraints and of installation locations

In this paper. power transfer capacity is investigated for systems with a unified power flow controller (UPFC). The combined effects of equipment constraints, system topology and installation locations on the UPFC real power transfer are studied. The R-Q characteristics of UPFC operation under different sets of constraints are determined. The admissible operational ranges of UPFC control outputs (in terms of the magnitude and phase angle of its series-injected voltage) are investigated, and the maximum power transfer and the maximum admissible range of power flow change are also found.