An Optimal Centralized Controller With Nonlinear Voltage Control

Power system multiswing transient stability during a disturbance may be substantially improved through proper control of power system bus voltages. These bus voltages are normally nonlinear functions of state variables defined for the generators and their control elements. Postfault changes in the power system may also require a power system operating point different from the prefault value. An optimal centralized controller capable of tracking these changes and controlling the nonlinear elements of the power system state vector is proposed in this paper. The primary role played by voltage control and the need to represent the dynamics of the external system are shown from the results of simulation case studies.