Basic Issues in Identification Scheme of a Self-Tuning Power System Stabilizer

Power system stabilizers have been widely used and successfully implemented for the improvement of power system damping. However, a fixed parameter power system stabilizer tends to be sensitive to variations in generator dynamics so that, for operating conditions away from those used for design, the effectiveness of the stabilizer can be greatly impaired. With the advent of microprocessor technology an adaptive controller, a controller which adapts itself to the changes in system dynamic characteristics, offers an attractive proposition in power system control. The heart of the so-called an adaptive self-tuning power system stabilizer is its identification scheme by which unknown system controller parameters are estimated. This paper addresses some of the basic issues in implementation of a recursive least square estimator, when applied to an unknown power system. Digital simulation results are presented.