Arman Fattollahi - Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
Majid Dehghani - Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran
Mohamad Reza Yousefi - Department of Electrical Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran

Power system is a nonlinear and temporal variable system. Different parts of the system change at different times and times with changing loads or loss of generators and disturbances. Power system stability and attenuation of low frequency fluctuations are very important. To increase the damping power and stability of the dynamic system, power system stabilizers are used to reduce fluctuations by generating additional control signals for the generator excitation system. In this paper, to improve the stability of the power system dynamic, a power system stabilizer based on synergistic control theory with an excitation system stabilizer according to a simplified nonlinear power system is used. The power system stabilizer has been studied in a single machine system connected to an infinite bus. The results show that the use of power system stabilizer and excita-tion system stabilizer for all nonlinear dynamic systems performs better than synergistic PSS, conventional PSS, and a system without stabilizer.

Stability, Power system stabilizer (PSS), excitation system stabilizer (ESS), Dynamic Behavior