Power system stabilizer for single machine infinite bus system for robustness against inertia constant variations

Abstract

Now a days the complexity of power systems increases drastically because of the growth of industries and domestic consumers. One of the major problems that can arise, in the contest of this growth, is low frequency oscillation, which can adversely affect stability of system. Power System Stabilizer (PSS) is generally used to repress the low frequency oscillation. It improves the system dynamic stability. PSS generates component of electrical torque in phase with the rotor speed variation. Variations in system inertia constant, significantly play a role in causing the low frequency oscillations, which in turn affect the power system frequency. The inertia constant also affects the manner in which a disturbed system regains its steady state. So in order to achieve a good frequency stability for single machine infinite bus(SMIB) system, it is important to have a robust PSS which can attain robustness against variations in inertia constant. This paper elucidates the design of the PSS for a simplified SMIB model using robust controller and robustness of the system against parameter variation in inertia constant. The ensuing Robust Power System Stabilizer (RPSS) ensures the stability and has superior oscillation damping capacity against system inertia constant.