A decentralized robust approach is proposed for the Automatic Generation Control (AGC) system based on a generalized AGC structure. This work addresses a new strategy to adapt well-tested classical AGC scheme to the changing environment of power system operation under deregulation. The effect of bilateral contracts is taken into Account in each control area dynamical model as a set of new input signals. In this paper, the PI-based AGC synthesis is formulated via an H∞ static output control problem and is solved using an iterative linear matrix inequalities (ILMI) algorithm. A three area power system example with possible contract scenarios and wide range of load changes is given to illustrate the proposed approach. The resulting controllers are shown to minimize the effect of disturbances and maintain the robust performance.
