Immersion and Invariance-Based nonlinear controller for a Power System with the excitation and STATCOM

In this paper, based on Immersion and Invariance (I&I) methodology, a nonlinear excitation and Static Synchronous Compensator (STATCOM) controller is proposed for the transient stability enhancement of an electrical power system. In particular, the simplified nonlinear model of power system elements and I&I design method are used to achieve not only power angle stability but also frequency and voltage regulations during a large (disturbance) perturbation (a symmetrical three-phase short circuit fault) on the transmission lines. The simulation results show that the proposed controller can not only keep the system transiently stable under severe disturbances but also simultaneously achieve power angle stability as well as frequency and voltage regulation.