Selftuning techniques for load frequency control

Abstract

The load frequency control of inter-connected power systems using the self tuning control techniques is presented in this thesis. Different self tuning techniques are analyzed and it is shown that with some controllers the integral action, which is essential to provide the zero steady state condition, is achieved as a result of the chosen predictive model. Some schemes where the integral action is achieved through the choice of the cost function and the predictive model as well as schemes with the integral action built into the control algorithm are presented. It is shown that the requirement of the integral action can be avoided by using a predicted load level variations as a feedback signal. It is also shown that for slow sampling rates the basic minimum variance controller can function but as the sampling rate is increased to cover the required band width, the controller fails. The application of pole assignment techniques and generalised minimum variance control techniques are considered and it is shown that a stable control situation can be achieved with sampling rates at which the minimum variance controller is unstable.