Fault Detection Strategy of Partial Least Squares Based on Temporal Neighborhood Difference

Abstract

Aiming at the difficulty of detecting time-lag faults in dynamic processes, a fault detection strategy based on time neighborhood difference (TND) is proposed, and it is introduced into the partial least squares (PLS) method to suggest the PLS-TND fault detection method. The TND method takes the mean to the multibatch training set to obtain a baseline training set, and it constructs the mean squared Euclidean distance (MSED) statistic by calculating the average distance between the sample's first k-moments neighborhood samples and samples at the same moment in the baseline training set. The TND method can help the PLS method to effectively detect time-lag faults and significantly improve the fault detection capability of PLS by measuring the overall positional difference between the temporal neighborhood sample set of the sample and its temporal neighborhood sample set in the baseline training set. The PLS-TND method is compared with some classical fault detection methods through a numerical simulation process and a Continuous Stirred Tank Reactor (CSTR) system design fault detection experiment. The PLS-TND method gives the best performance of fault detection.