Due to the change of working conditions, external interference and modeling errors, it is difficult to obtain an accurate model of the actual industrial process, and various failures of the system will also lead to the uncertainty of the model, so it can be said that the uncertainty of the model widely exists in the control system. How to design a fixed controller to make uncertain objects meet the control quality, that is, robust control, has become a research topic for researchers at home and abroad.
198 1: Zames takes the H∞ norm as the performance index, and puts forward the minimum sensitivity control problem-H ∞ control problem;
1988: The state feedback control solution of the H∞ control problem is obtained every week;
1989: Doyle published a famous DGKF paper, and obtained the output feedback control solution of H∞ control problem-the formation of H ∞ control theory.