Robust design of excitation controller for transient stability and voltage regulation in power systems

This paper deals with the problem of transient stability and voltage regulation in power systems control. When a large change of operating point occurs, caused for example by short-circuit fault, the parameters of the power system model vary. Their variations are unknown but limited to a given interval. A robust control technique based on the solution of a Riccati equation is adopted to design a state feedback excitation controller which guarantees both stability and voltage regulation objectives. The control objectives are achieved in spite of the presence of unknown bounded L1 disturbances in the power system model. To evaluate the performance achieved by the designed controller, a three-phase short-circuit fault near the generator terminal in a four-buses power system is simulated.