Patent ID: 6192352
Filing Date: 2001-02-20
Classification: G05B,G06N,Y10S

Abstract:
A process for determining the occurrence and location of a boiler tube leak event in industrial/utility boilers, said process comprising:(a) determining for a boiler, a set of tube universal leak sensitive variables ULSVs;(b) calibrating the relationship between teaching data consisting of a plurality of known output patterns for each of said ULSVs in said set determined in step (a), and learning sample data consisting of a plurality of sample patterns obtained from actual boiler tube leak events, or simulated boiler tube leak events, or both, by training a universal leak detection system (ULDS) Artificial Neural Network (ANN) by supplying said learning data thereto and comparing said learning data with the corresponding teaching data patterns to thereby achieve a predetermined degree of convergence towards maximum pattern learning recognition;(c) determining for said boiler, a set of tube local leak sensitive variables LLSVs;(d) for each of said LLSVs determined in step (c), calibrating the relationship between teaching data consisting of a plurality of known output patterns for each individual variable of said LLSVs and learning sample data consisting of a plurality of sample patterns obtained from actual boiler tube leak events, or simulated boiler tube leak events, or both, by training, for each such LLSV, a corresponding a local leak detection system (LLDS) ANN forming a part of a group of LLDS ANNs by supplying said learning data thereto and comparing same with the corresponding teaching data patterns to thereby achieve a predetermined degree of convergence towards maximum pattern learning recognition;(e) thereafter monitoring said industrial/utility boilers for the occurrence of a leak event by observing changes in values in a given boiler for each of said ULSVs and supplying said observed changes in values to said ULDS ANN for calculating a possibility that a leak event is occurring in the given boiler;(f) comparing the possibility calculated in step (e) to a predetermined confidence threshold;(g) if the possibility compared in step (f) is greater than said confidence threshold, concluding that a leak event is occurring and thereafter observing changes in values from said boiler for each of said LLSVs and supplying said observed changes in values to each of said corresponding local leak detection system (LLDS) ANNs for simultaneously calculating a possibility that the leak event is occurring at the location corresponding to one of a subsystem of the boiler; and(h) comparing each possibility calculated by each LLDS ANN in step (g), one with the other, and concluding from said comparisons the location, in said boiler, of said leak event.