Tube-based Robust Fault Estimation Integrating Unknown Inputs Decoupling and Set-membership Approach

摘要

This paper proposes a novel tube-based robust fault estimation (FE) method for dynamic systems by decoupling unknown inputs and using set-membership approach. FE problems are considered in a novel prospective in this paper. Instead of estimating a specific fault value like most of FE methods, in order to guarantee the FE robustness, we compute a fault tube to contain the real fault at each time instant under an assumption that the system uncertainties (i.e., modeling errors, process disturbances and measurement noises) are bounded. Theoretically, any trajectory in the fault tube can be used as an estimation of the real fault. The size of the tube indicates the performance of FE. That is, the smaller the tube is, the better the obtained FE results are. At the end of this paper, a numerical example is used to show the effectiveness of the proposed robust FE approach.