MNCMD-based Causality Analysis of Plant-wide Oscillations for Industrial Process Control System

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.

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Nitrogen removal in a SBR using the OGAR process control system

Water Science & Technology ◽

10.2166/wst.2002.0567 ◽

2002 ◽

Vol 46 (4-5) ◽

pp. 125-130 ◽

Cited By ~ 2

Author(s):

Z. Tomlins ◽

M. Thomas ◽

J. Keller ◽

J.-M. Audic ◽

V. Urbain

Keyword(s):

Control System ◽

Process Control ◽

Total Nitrogen ◽

Environmental Protection Agency ◽

Batch Reactor ◽

Industrial Process ◽

Ammonia Concentration ◽

Process Control System ◽

Treated Effluent ◽

On Line

OGAR® is an industrial process control system that utilises on-line redox measurements to control the aeration sequence in an activated sludge process. Compared to conventional process control systems that use dissolved oxygen, OGAR® makes use of redox as a control parameter during both aerobic and anoxic conditions. This paper reports on its first application in a sequencing batch reactor. The principal aim of this project is to demonstrate the capability of OGAR® to achieve concentrations of total nitrogen in the treated effluent of less than 10 mg/L, which are typically stipulated by Queensland's Environmental Protection Agency (EPA). In this study the use of the control system resulted in the following SBR performance: consistent effluent total nitrogen less than 5.0 mg/L; ammonia concentration reduced from 31.6 mg/L to 0.32 mg/L, effluent nitrate 2.8 mg/L; DO setpoint 1.5 mg/L had 10% higher effluent total nitrogen compared to DO setpoint 4.0 mg/L and redox end-points for nitrification 400 mV, denitrification 150 mV.

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Development of Resilient Control Systems for Technological Plants

Problems of the Regional Energetics ◽

10.52254/1857-0070.2021.2-50.10 ◽

2021 ◽

Vol 2(50) ◽

Author(s):

Andrey Stopakevych ◽

◽

Aleksey Stopakevych ◽

Keyword(s):

Control System ◽

Process Control ◽

Control Systems ◽

Distillation Column ◽

Production Systems ◽

Industrial Process ◽

Modern Theory ◽

Linear Quadratic ◽

Process Control Systems ◽

Industrial Process Control

The aims of the research are increasing resiliency of industrial process control systems, the de-velopment of methods of creating resilient industrial process control systems and creating a resil-ient control system of the distillation column for the production of food alcohol. The set of ob-jectives were achieved without the use of hardware backup, but using the developed algorithms which were based on the use of the model of dynamics of technological plants in the software of the control system and modern theory of multivariable automatic control systems. The opti-mal linear-quadratic controller with disturbances model and a state observer was used as a full controller. The most important result was improvement of the survivability of industrial process control systems using the developed algorithm. Also, the resilient distillation column control sys-tem was developed. For the further researches significant results are formulas which allow de-fining new mode values of controls in a distillation column at failure event of corresponding control output channels and formulas of logic algebra for a choice of optimum configuration of control system of a distillation column of food spirit industry. The basis of the developed tech-nique was reconfiguration of the control system with inclusion, instead of the failed, additional devices, which were not being used in a current configuration, but were carried out the similar function taking into account dynamics coupling of a technological plant. The significance of these results is that they can be applied to the development of cyber-production systems that do not require permanent maintenance by personnel.

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