Grey prediction theory and extension strategy-based excitation control for generator

•The grey prediction technology and extension control strategy are used to design excitation controller.•The nonlinear characteristics and time-varying conditions of modern power system are all considered.•Effectiveness of proposed scheme is validated under various operating mode.•Comparison of proposed scheme with classical PID controller and single extension controller.

The nonlinear characteristics and time-varying conditions of modern power system make the classic linear control method incapable of action, meanwhile the existing nonlinear control methods and the intelligent control technology cannot obtain satisfactory control effect. A novel excitation controller is proposed based on grey prediction technology and extension control strategy, which can improve the power system stability to a greater degree because it combines the former ‘prior control’ and the latter’s advantage that does not require a precise mathematical model and the real-time performance is good. The simulation results on a single machine infinite bus power system and multi-machine system show that the grey prediction extension excitation controller has better control effect compared with traditional control mode and general extension control method.