Decentralized coordinated control for large power system based on transient stability assessment

For the purpose of enhancing transient stability of large power systems, this paper focuses on an issue of decentralized coordinated control. A modified equal area criterion (MEAC) is firstly proposed as the transient stability judgment criterion of multi-machine power systems. Then, a hierarchical decentralized coordinated excitation control is designed, which consists of both upper level coordinated control and lower level decentralized control. Based on the transient stability assessment, the coordinated controller determines whether to send coordinated control signal to lower level decentralized controllers. Moreover, the decentralized coordinated controller is designed by using H∞ robust control method so as to deal with the uncertainties of system. Finally, simulation studies test effectiveness of the proposed control.

► The transient stability judgment criterion of multi-machine system is presented. ► A decentralized coordinated control is developed based on the judgment criterion ► A DFL compensator is employed to deal with the nonlinear interconnected model. ► H∞ robust method is proposed to handle the uncertainties of model. ► The H∞ control problem is transformed into minimization problem of LMIs.