The Interline Power Flow Controller (IPFC) is one of the recently developed Flexible AC Transmission System (FACTS) devices. The IPFC is realized by two voltage source converters connected by a common DC link. Fuzzy logic (FL) controllers are designed to operate the controls of IPFC for damping the power system oscillations. The proposed FL controller uses machine speed and its integral as its inputs and the output of the controller controls the input signal of the IPFC. The effectiveness of the fuzzy controller is tested on a single machine infinite bus power system operating with an IPFC for various disturbances and operating conditions. The performance of the proposed controller is compared with the conventional controller of the IPFC and the results of time-domain simulation studies show that the designed FL controller provides enhanced damping of power system oscillations. © 2010 Praise Worthy Prize S.r.l.