Design of robust H∞ PI controller for hydro turbine speed governor

This paper presents the design of the H_∞ robust performance of a hydro turbine speed governor. It can be used to solve the H_∞ robustness problems of the hydro turbine speed governor, which can´t be done by the conventional H_∞ double-Loop robust performance designs. High frequency oscillation and large amplitude of output and control variable of the control system of the hydro turbine speed governor are exhibited by a conventional H_∞ double-Loop robust performance design method. It is pointed out that the design of the robust performance of the hydro turbine speed governor can be formulated as an optimization H_∞ mixed sensitivity method, if the uncertainty weighting function and the performance weighting function of the hydro turbine speed governor are revised appropriately. The selections of the weighting functions are studied and the optimization H_∞ mixed sensitivity robust PI controllers of the hydro turbine speed governor are solved. The simulation results of the hydro turbine speed governor show that the proposed method is valid. The realization of the controllers doesn´t involve extra cost to the control equipment of the hydro turbine speed governor.