Hierarchical frequency-domain robust component failure detection scheme for large-scale analogue circuits with component tolerances

A hierarchical frequency-domain robust component failure detection (RCFD) scheme is proposed for the robust fault diagnosis of large-scale analogue circuits with both component tolerances and measurement errors. In the proposed scheme, robust detection filters designed by using the full-rank measurement for each hierarchy of the stratified circuit are employed to generate the robust residuals for fault isolation (FI), and the effect of both component tolerances and measurement errors to the diagnostic result is reduced by using the carefully evaluated residual thresholds, and the RCFD is achieved. In the paper, the design of the robust detection filters and the evaluation of the residual thresholds are presented and a circuit-hierarchical full-rank measurement condition is proposed. A large-scale analogue circuit is illustrated. The results indicate that, without any a priori information about the type of component failure, precise diagnosis for a large-scale circuit with both component tolerances and measurement errors is accomplished at low measurement cost