Distributed Fault Detection for Large-Scale Systems: A Subspace Intersection-Based Scheme to Accurately Monitor the Impact of Fault Propagation

Considering that the interaction information between neighbor subsystems is unmeasurable, this article investigates the problem of distributed fault detection (FD) for individual subsystems in a large-scale system. Unmeasurable interaction terms as unknown inputs to subsystems pose a challenge for distributed FD. To cope with this problem, in this article, a distributed FD scheme for large-scale systems is proposed, which utilizes only local and neighbor input and output data information to achieve the estimation of the unknown input term by subspace intersection. In addition, a data-driven distributed residual generator construction method is designed based on the estimated unknown input term. Meanwhile, the rank conditions that need to be satisfied by the distributed method are provided. Finally, the effectiveness of the proposed method is verified and discussed in a simulation example and a real manufacturing case.