The stability of interconnected power system is compared with normal or stable operation after subjected to some form of disturbance. With interconnected systems continually growing in size and extending over vast geographical regions, it is becoming increasingly more difficult to maintain synchronism between various parts of the power system. This project investigates the Custom Power Active Transformer (CPAT) capability to provide UPFC services which includes power flow control, reactive power compensation, voltage regulation and harmonics elimination. Simulations of the Fuzzy- UPFC with a...