UPFC Power Frequency Model for Power System Stability Analysis

Abstract In this paper a power frequency model is derived for unified power flow controller (UPFC). The UPFC capacitor charging dynamics is considered. Its shunt part control is to keep constant the UPFC terminal bus voltage magnitude and the UPFC capacitor voltage respectively. Its series part control is to keep constant real and reactive power flow of the UPFC-installed line or to act as a series compensator. The integrated UPFC model has been incorporated into power system transient stability program with a novel interface. Computer tests on a 4-generator power system show that the suggested UPFC model and the UPFC-network interface method work very well in transient stability analysis. The tests also show that the different control strategies might have distinct effects on system stability performance.