CONTROL SYSTEM AND METHOD FOR DETECTING PLUGGING IN DIFFERENTIAL PRESSURE CELLS

摘要

A method and control system that monitors the high frequency or commonly referred to as the "noise" component of a measurement signal to detect plugging conditions in fluid flow systems monitored by DP-cell based sensors. This high frequency component has contributions from the process factors like disturbances, user actions and random effects like turbulence. A test statistic theta(t) has been developed that monitors the proportion of variance introduced by the first two factors and the third factor. By monitoring this proportion, it is possible to detect a frozen sensor that is characterized by a dramatic reduction in the variance due to process factors over a sufficiently long detection window. The method and control system uses random sampling intervals to improve data quality. The sampling rate is also reduced by taking samples at a lower rate and then reconstructing the original signal from fewer data points.