Design of Power System Stabilizer using Fuzzy Based Sliding Mode Control Technique

Power systems are usually large non-linear systems, which are often subjected to low frequency electromechanical oscillations. Power System Stabilizers (PSSs) are often used as effective and economic means for damping the generators’ electromechanical oscillations and enhance the overall stability of power systems. Power system stabilizers have been applied for several decades in utilities and they can extend power transfer stability limits by adding modulation signal through excitation control system. Sliding mode control is one of the main methods employed to overcome the uncertainty of the system. This controller can be applied very well in presence of both parameter uncertainties and unknown nonlinear function such as disturbance. To enhance stability and improve dynamic response of the system operating in faulty conditions a Fuzzy based Sliding Mode Control PSS is developed for a multimachine system with two generators and it is compared with the Conventional PSS, Fuzzy based PSS, Sliding Mode based PSS.