Fuzzy Evidential Approximate Reasoning Scheme for fault diagnosis of complex processes (original) (raw)

An intelligent diagnostic scheme using sensor network for incipient faults is proposed using a holistic approach which integrates model-, fuzzy logic-, neural networkbased schemes. In case the system is highly non-linear and there are enough training data available, a neural network based scheme is preferred; where the rules relating the input and output can be derived, a Fuzzy-logic approach is chosen; and where a model is available, a linearized model is employed. These three schemes are integrated sequentially ensuring thereby that critical information about the presence or absence of a fault is monitored in the shortest possible time, and the complete status regarding the fault is unfolded in time. The proposed scheme is evaluated extensively on simulated examples and on a physical system exemplified by a benchmarked laboratoryscale two-tank system to detect and isolate faults including sensor, actuator and leakage ones.