PSSs design based on PMUs signals to enhance the stability of inter-area oscillations of interconnected power systems

Poorly damped or unstable mode of inter-area oscillations is undesirable as they result in inefficient operation of the power systems. Without proper remedial actions, these oscillations can result in power systems separation or major blackouts. Adequate damping of these oscillations is a pre-requisite for secure operation of power systems. An available solution to damp out these inter-area oscillations is the addition of power system stabilizers (PSSs) to the excitation systems of the generators. Although conventional PSSs exist on many generators, their effect is only on the damping of local oscillations and do not effectively damp out inter-area oscillations. In this paper a robust PSS based on PMU signals is proposed to ensure satisfactory damping of inter-area oscillations which result in enhancing system stability and maximizing power transfer capacity. The signal input to the proposed PSSs are detected and transmitted by the PMUs. Modal analysis and time-domain transient simulation results show that inter-area oscillation damping was improved effectively with the proposed PSSs.