An Eigenstructure Assignment Approach to the Design of Unknown Input Fault Isolation Observer (UIFIO)

• Main Authors: Li-Cheng Shen, 沈里正
• Other Authors: Pau-Lo Hsu
• Format: Others
• Language: en_US
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/22950787411084909628

碩士 === 國立交通大學 === 控制工程系 === 82 === As the demands on safety and reliablity of automatically co- ntrolled system become more stringent,a good control system has to not only achieve the performacne requirements but also guara- tee the safety concern. In this thesis, an UIFIO (unknown input fault isolation obs- erver) will be firstly proposed with eigenstructure assignment and the corresponding numerical algorithm will also be summari- zed. With the flexiblity provided by output feedback in multiva- riable systems beyond closed-loop eigenvalure assignment, the f- ault diagnostic observer decouples the structured uncertanity f- rom residual outputs and performs isolation for any possible co- mbination of failure occurrences. Furthermore, since the robust- ness of the diagnostic observer relative to unstructured uncert- ainty depends on the condition number of closed-loop eigenvecto- r set, two constrained approximations for minimizing condition number of closed-loop eigenvector assignment based on the UIFIO are proposed. With these two approximation methods, a locally optimal solution of closed- loop eigenvector set can be found to suppress the effects induced by unstructured uncertanity.