Abstract Interval fault estimation in linear dynamic systems under measurement noise and external disturbances is considered. This problem is solved using the methods of optimal control and interval observers by transforming the original system into a reduced model that is sensitive to faults and insensitive to disturbances. An astatic mode in the observer is used to improve the estimation accuracy. This theory is illustrated by the well-known example of the three tank system.
Zhirabok et al. (Wed,) studied this question.