Robust fault diagnosis for large-scale analog circuits with measurement noises

A hierarchical frequency-domain robust component failure detection (RCFD) scheme is proposed for the diagnosis of large-scale analog circuits with measurement noises based on the design of robust detection filters and robust residual thresholds. The robust residuals generated by the robust detection filters are employed to realize both fault isolation (FI) and component failure detection (CFD). A procedure for the design of robust detection filters is proposed and the associated rule for the selection of measurement variables is suggested. Furthermore, the effect of the measurement noises to the diagnostic result can be reduced by the proper design of residual thresholds, and the robustness of the diagnosis is enhanced. Finally, an example is illustrated to show the efficacy of the proposed method.