Controller design for voltage regulation and stabilization in multimachine power systems

This paper deals with the problem to guarantee system stability and voltage regulation in multimachine power systems. The power system is decomposed in n subsystems each one containing a synchronous generator. For each subsystem two input-output models of low order are derived modelling the electrical and mechanical dynamics, respectively. Each model presents parameter uncertainties and input disturbance. A voltage controller based on the internal model control is designed and sequentially a stabilizing controller (PSS) is designed so as to enhance swing damping. According to the decentralized approach, the controllers use only locally available measurements. Numerical simulation studies conducted on a three machine test power system show the performance obtained in the presence of severe contingencies.