Optimal Design of robust Power System Stabilizers Using Hybrid Big Bang-Big Crunch Algorithm

Power systems are subjected to disturbance that may cause unacceptable power variations in transmission lines. Thus there is a need to find a way to damp these oscillations. Using a Power System Stabilizer (PSS) is a way for damping oscillations. The action of a PSS is to extend the angular stability limits of a power system by providing supplemental damping to the oscillation of synchronous machine rotors through the generator excitation. This damping is provided by an electric torque applied to the rotor that is in phase with the speed variation. A coordinated PSS setting will have an influence on the system performance. This paper presents a Hybrid Big Bang-Big Crunch (HBB-BC) algorithm to tune optimal power system stabilizer which leads to damp low frequency oscillation (LFO) following a 70ms three phase to the ground fault in power systems. To ensure performance and robustness of the proposed control strategy to stabilize low frequency oscillations the design process takes a wide range of operating conditions. The results show the effectiveness of the proposed PSS in damping power system oscillations over a wide range of power system operation and it is superior to the other PSSs.