Causality analysis in process control based on denoising and periodicity-removing CCM

Abstract

Purpose1. To improve the causality analysis performance, a novel causality detector based on time-delayed convergent cross mapping (TD-CCM) is proposed in this work. 2. Identify the root cause of plant-wide oscillations in process control system.Design/methodology/approachA novel causality analysis framework is proposed based on denoising and periodicity-removing TD-CCM (time-delayed convergent cross mapping). We first point out that noise and periodicity have adverse effects on causality detection. Then, the empirical mode decomposition (EMD) and detrended fluctuation analysis (FDA) are combined to achieve denoising. The periodicities are effectively removed through singular spectrum analysis (SSA). Following, the TD-CCM can accurately capture the causalities and locate the root cause by analyzing the filtered signals.Findings1. A novel causality detector based on denoising and periodicity-removing time-delayed convergent cross mapping (TD-CCM) is proposed. 2. Simulation studies show that the proposed method is able to improve the causality analysis performance. 3. Industrial case study shows the proposed method can be used to analyze the root cause of plant-wide oscillations in process control system.Originality/value1. A novel causality detector based on denoising and periodicity-removing time-delayed convergent cross mapping (TD-CCM) is proposed. 2. The influences of noise and periodicity on causality analysis are investigated. 3. Simulations and industrial case shows that the proposed method can improve the causality analysis performance and can be used to identify the root cause of plant-wide oscillations in process control system.

Controller Performance Monitoring: A Survey of Problems and a Review of Approaches from a Data-Driven Perspective with a Focus on Oscillations Detection and Diagnosis

“…This method outperforms GC regarding its unrealistic assumptions and transfer entropy in terms of computational costs. Chen et al 186 attempted to bridge this gap by employing denoising and periodicity-removing time-delayed convergent cross mapping (TD-CCM). TD-CCM is a new variant of CCM that incorporates a time lag between the cause and effect in order to get a more accurate causality inference.…”

Detecting and Diagnosing Process Nonlinearity- Induced Unit-Wide Oscillations Based on an Optimized Multivariate Variational Mode Decomposition Method

“…It was an orifice plate flow meter but there was no weep-hole in the plate which had the effect that condensate collected on the upstream side until it reached a critical level, and the accumulated liquid would then periodically clear itself by siphoning through the orifice [41]. The challenge for the analysis of this system is to verify that the nonlinearity faulty steam flow loop is the root cause of the unit-wide oscillations [4].…”

“…They may be caused by excessive controller gain or external disturbance, but a more common cause of oscillation is valve stiction, which is the most typical nonlinear fault in process control system [2], [3]. Due to the interconnection between loops, the oscillation generated by one control loop is easy to be transmitted to other loops to form unit-wide oscillations [4]. Therefore, the motivation of this work is to detect and diagnose the nonlinearity-induced unit-wide oscillations in the process control system to improve the safety and economy.…”