Lyapunov based Η∞ controller design in multimachine power systems

In this paper, nonlinear H_∞ controller problem in large-scale systems is investigated. The paper needs to find an energy function which satisfies the Hamilton Jacobi inequality. The energy function of the whole large scale system is considered to be the sum of the energy functions of the isolated subsystems. When the inequality is solved, a decentralized state feedback controller for each subsystem is obtained. The controller can be implemented locally in each subsystem. The method is tested on a sample multi-machine power system model. Simulation results show the effectiveness, robustness and good performance of the proposed controller.