Global control of multi-machine power systems for transient stability enhancement

This paper presents a global control strategy for multi-machine power systems to enhance transient stability. The global control system models are proposed to represent the power systems with abrupt structure changes. Multi-machine power systems are first represented by interconnected subsystems with uncertainties and nonlinearities. Then each subsystem is decomposed into four nonlinear partial systems according to switching actions of breakers under a severe disturbance. The partial feedback controllers are respectively designed for partial models and the decentralized controllers for each subsystem are obtained through membership functions. Finally, the global controller is the summation of all the control actions from every subsystem. A three-machine power system is used as an example to demonstrate the effectiveness of the proposed global control strategy for multi-machine power systems.