Robust controller design for generator excitation systems

This paper deals with the design and evaluation of a robust controller for generator excitation systems to improve the steady-state and transient stabilities. The unique approach used is to first treat the nonlinear characteristics of the system as model uncertainties, and then to take into account such uncertainties at the controller design stage using a robust control methodology. The performance of the controller has been evaluated extensively by nonlinear simulation. It is concluded that the robust controller provides better damping to the oscillatory modes of the system than the conventional PSS in all the cases studied