Numerical Solution of H∞ Observer Gain in Electro-hydraulic Servo Systems

In this paper, we study the iterative technique to find the solution of the $H$ ∞ filter gain in electro-hydraulic servo systems. Firstly, a full-state observer is introduced in the electro-hydraulic servo systems for fault diagnosis. Secondly, the $H$ ∞ filter is used to determine the performance index of the observer. Finally, a novel iterative method is constructed for solving the associated algebraic Riccati matrix equation, and the observer gain is obtained. In addition, a practical example is given to demonstrate the efficiency of the proposed method.