Distributed Unknown Input Observers for Fault Detection and Isolation
Sam Nazari, Bahram Shafai · 2019
This paper considers observer based fault detection and isolation in a distributed setting with agents under consensus dynamics. The distributed fault detection and isolation problem is introduced along with system models to represent nominal and faulty conditions. It is shown that the positive unknown input observer (PUIO) effectively estimates the fault signal in an agent and that it can be used for residual generation and fault isolation. The conditions under which fault isolation is achievable are derived as a function of the distributed topology of the agents in the network. An LMI is derived that can be used to conveniently obtain the residual generator gains. The distributed PUIO design approach is illustrated with an example.