Frequency Domain Approaches to Fault Detection in Closed-Loop Systems

[摘要] This thesis describes fault detection techniques which can be applied to closed-loop automatic control systems. Particular emphasis is placed upon frequency domain methods. Digital simulation is used for the evaluation of on-line techniques for fault detection using pseudo-random-binary test signals. This simulation work involves a simple process model based on a two tank liquid flow control system. Frequency-domain identification using pseudo-random-binary test signals is performed by means of a mixed radix-2 fast Fourier transformation technique. This technique avoids the synchronisation problems which arise when the more conventional radix-2 transformation is used with pseudo-random binary test signals. A novel method of parameter sensitivity analysis is investigated both in terms of the identification of faults and for system optimisation following fault occurrence.

[发布机构] University:University of Glasgow

[关键词] Electrical engineering