Index TermsaModaIControITheory, SSR, FACTS I. INTRODUCTION SERIES capacitor compensation is employed in electric power ... However, so far, little work has been done due to the SSR problems of a power system installed with a UPFC. ... transfonner (ET), a boosting transformer (BT), two three-phase GTO based voltage source converters (V SCs) and a DC link capacitor. ... K6, , = 2.822 M X = 0.063433 DH=D!=DA=DB=DG=DX=0.l Turbine torques and govemor F, ., = 0.