DESIGN OF A REDUCED-ORDER ADAPTIVE LOAD-FREQUENCY CONTROLLER FOR AN INTERCONNECTED HYDROTHERMAL POWER-SYSTEM

This paper proposes an adaptive controller for load-frequency control of interconnected power systems. The proposed controller uses a signal synthesis adaptation approach such that the performance of the contro lled system is insensitive to the changing load and system parameter v ariations. It is designed such that only the outputs of the controlled plant are fed back to the controller. A reduced reference model is us ed to simplify the design, making the controller easier to implement. The effectiveness of the proposed controller is illustrated by digital simulation of an interconnected power system consisting of a hydro pl ant and a steam plant. The results show that the performance of the pr oposed controller is comparable with that obtained from a full state f eedback optimal controller, and the performance is rather insensitive to the variations of system parameters.