The Design of Reduced-order Observer for Systems with Monotone Nonlinearities

<正>Based on the discussion about the existence and design method of full-order observer for systems with monotone nonlinearities,a reduced-order observer design method is developed under the assumption that a linear matrix inequality(LMI) has positive definite matrix solution and the reduced-order observer gain matrix is computed by the solution of LMI.By a linear transformation,a reduced-order observer which does not contain the information of the derivative of the system output is provided. A model is simulated and some conclusions are drawn based on the comparison of the results of reduced-order observer to that of full-order observer.The simulation shows that the design method developed by this paper has good performance.