Mohammad Hadi Tofighi - School of Mechanics, Electrical and Computer engineering Science and Research Branch Islamic Azad University,SRBIAU Tehran,Iran
Faramarz Faghihi - School of Mechanics, Electrical and Computer engineering Science and Research Branch Islamic Azad University,SRBIAU Tehran,Iran
Fatemeh Tofighi - School of Electrical and computer engineering University of Science and Technology of Mazandaran, MAZUSTBehshahr,Iran

Small changes in load cause disorders in the powersystem, which ultimately leads to instability of power systems.The disturbances caused by the load cause low frequencyoscillations and create inappropriate levels of transmissionpower. In this paper, an adaptive fuzzy sliding mode powerstabilizer (PSS) is presented to reduce the oscillation for a twoareafour machine power system. The input signals of the fuzzylogic controller are deviation of the generator speed and itsderivative, and the integral regulator is used to filter the slippingcollisions. The stabilizer function of the power system designedwith adaptive fuzzy sliding mode for the two-area four machinepower system different types of turbulence has been investigatedand evaluated. Simulation is implemented in MATLAB software.The simulation results of the proposed method have beencompared with the results obtained from a conventional powersystem stabilizer (CPSS) and a sliding mode based power systemstabilizer. The results show the robustness and performance ofthe proposed method.

Sliding mode control; Fuzzy logic; Adaptive control; Power system stabilizer