Robust multivariable-cascade governors for hydroturbine controls

摘要

This paper proposes a new robust multivariable-cascade governor that is based on the polynomial H{sub}∞ optimisation method for hydroturbine speed controls. Only the bound of uncertainty is required to design a robust governor. Impacts of disturbance and uncertainties are briefly discussed to investigate robustness and performance measures of the system. A nonlinear turbine model that includes effects of water hammer, travelling waves and inelastic water penstocks, and disturbance models is considered in the robust design procedure. The robust governor ensures that the overall system remains asymptotically stable for all permissible norm-bounded uncertainties and for system oscillations. Simulation results illustrated in time and frequency domains show the feasibility of the approach and the factors involved in design such that the proposed robust governor even in the presence of norm-bounded uncertainties improves the performance significantly.