Method for designing industrial alarm on basis of alarm evidence fusion

Abstract

The invention relates to a method for designing an industrial alarm on basis of alarm evidence fusion, which belongs to the technical field of industrial alarm design. The method is based on a fuzzy subjection function to construct a fuzzy threshold, the measured values of a process variable at each moment are compared with the fuzzy threshold to calculate an alarm evidence, and the alarm evidence shows the uncertainty degree that the value of the process variable exceeds or is lower than the fuzzy threshold; a linear weighting evidence is utilized to update rules, the alarm evidence of the current moment is fused with the alarm evidence in the past time, so the whole alarm evidence of the current moment is obtained, the alarm is judged to be sent out or not according to related judgment standards, the fusion process can effectively reduce the influence of uncertainty, so the alarm accuracy is improved; and a test sample is extracted according to the measured data of the process variable. A method for finding out the optimal fuzzy threshold under the lowest false alarm rate and missing report rate standards is provided.

Description

technical field [0001] The invention relates to an industrial alarm design method based on alarm evidence fusion filtering, and belongs to the technical field of industrial alarm design. Background technique [0002] In petrochemical and other industrial fields, the over-limit alarm of the main operating process variables of large-scale equipment is an important means to grasp the operation of the equipment and find out the abnormality or failure of the equipment in time. The alarm generated by the alarm can remind the equipment operator or maintenance personnel to take measures such as shutting down or degrading operation in time to ensure that the equipment is not subject to more serious damage. Whether the alarm will alarm or not depends on whether the monitored process variable triggers the set alarm threshold. However, in practical applications, when the alarm threshold is not designed properly, false positives or even alarm floods and missed negatives often occur. Th...

AI Technical Summary

Problems solved by technology

Several commonly used alarm design methods such as digital filtering, time delay, and dead zone setting have been given in the standards of the British Engineering Equipment and Materials Users Association, but the discrimination methods of these traditional methods are based on absolute thresholds, that is, process variables If the threshold is exceeded, the alarm will be issued immediately, and if the alarm is lower than the threshold, the alarm will be released immediately

However, the design idea of ​​this absolute threshold cannot well eliminate various uncertainties in equipment operation and sensor information collection, so it cannot completely and effectively reduce the rate of false alarms and false negatives, and ultimately improve the accuracy of alarms. the goal of

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