Large power systems stability enhancement using a delayed operation fuzzy logic power system stabilizer

This paper presents a novel control operation of fuzzy logic pourer system stabilizer (FLPSS) for stability enhancement of a large-scale pourer system. The FLPSS is applied for each machine in the system while its operation is delayed for a short period almost equal to the first half cycle of the power system electromechanical oscillations. The application of this controller is successful in damping large-scale power system oscillations. In order to accomplish best damping characteristics, two signals are chosen as inputs to the FLPSS; deviation of power angle (Delta(delta)over dot) and deviation of speed derivative (Delta(omega)over dot),of each synchronous machine in the system. These two variables have efficient effects on damping the oscillations of both frequency and terminal voltage signals and hence the system gives better stability. The effectiveness of this delayed operation FLPSS controller is demonstrated by a digital computer simulation of a large-scale power system.