Design of Power System Stabilizer using Sliding Mode Control Technique for Low Frequency Oscillations Damping

This paper proposes a novel and robust sliding mode controlled power system stabilizer (SMCPSS) for damping the oscillations of low frequency in interconnected power system. The unique characteristic of sliding mode controlled stabilizer is its robustness and its insensitivity to the system parameter variations, when there is an occurrence of perturbations in the system. The input signal considered for the SMCPSS is the speed deviation of the synchronous generator. The closed loop characteristics of the SMC have derived with the help of phase portrait obtained from the sliding trajectory and control law has been defined. The proposed method is tested in single machine and multiple machine system. A comparison of the performance of the proposed approach has been carried out with different conventional techniques. Simulation results shows that SMCPSS is more effective than other conventional control techniques, in damping the oscillations.