An Iterative Unknown Input Observer Design

Abstract:

Based on the thought of iterative control, this paper presents a method to design an unknown input observer for linear continuous time systems with unknown input. In each step of iteration, the current input of iteration is known, so the traditional Luenberger observer is used to estimate the current system state and corresponding output. Based on D type iterative learning control algorithm, the iterative method to estimate the unknown input of next step is proposed by using the current output error and estimated input, and the Luenberger observer is redesigned by using the estimated value to estimate the next step system state. The convergence of the iterative algorithm is analyzed, and the sufficient condition for its convergence is given. Finally, a numerical simulation of a practical model is given to illustrate the effectiveness of the proposed methods.