Design of Power System Stabilizer based on Partial Parameter Identification

Abstract

In this paper a design method of the robust PSS (Power system Stabilizer) is presented on the basis of the identified model. The basic idea is to partially identify each generator, which connects with a large-scale power system, as a single-machine infinity-bus system. Whereas the structure of mathematical model and parameters of each generator are regarded as already known, the only unknown parameters are equivalent reactance of transmission lines, the voltage and the phase angle of infinity bus system. The novel idea is that known and unknown parameters are coded in one system matrix, and the guessed values of unknown parameters are estimated by identification process. The controller is designed by applying H^∞ control theory to the identified model and the obtained controller is reduced to the reasonable order. It is found that the time response of identified model closely resemble the simulated response, and the controller are almost not degraded by order reduction. Effectiveness of the proposed method is verified through some nonlinear simulations for the three machine system of radial type.