Tag Archive: process

Jun
10

Application of Kalman Filtering in DeltaV

Kalman Filter

A paper published in 1960 by Rudolf Kálmán “A New Approach to Linear Filtering and Prediction Problems” is the basis for the Kalman Filter. The Kalman filter has been successfully used in a wide variety of applications: • The guidance of commercial airplanes • Seismic data processing • Nuclear power plant instrumentation • Vehicle navigation …

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May
27

Commissioning PI Control – Integrating Process

Three Element Drum Level Control

When the control objective is to maintain the controlled parameter of an integrating process at setpoint under all operating conditions, then using PI (proportional-integral or proportional plus reset) controller, it is possible to automatically compensate for changes in disturbance inputs and maintain the controlled parameter at setpoint. However, the application of PI control to an …

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May
06

On-demand Tuning Example

On-Demand Tuning Example

Control system manufacturers have adopted different technologies to implement on-demand tuning. Because these tools are designed to work in a noisy process measurement environment, the tuning results are usually better than those achieved through manual tuning techniques. To illustrate the features that may be included in on-demand tuning capability, the on-demand tuning capability of the …

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Apr
22

Capturing Process Dynamics

Structuring On-demand Tuning

When the on-demand tuning application resides in a DCS workstation, communications between the controller and the workstation can introduce variable delay and jitter in the observed process response. As addressed in Chapter 4 of Advanced Control Foundation – Tools, Techniques, and Applications, the process may be more accurately identified by distributing the on-demand tuning functionality …

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Apr
15

On-Demand Tuning

Self Regulating Response

During the commissioning of feedback control based on the PID algorithm, the PID tuning parameters (that is, the proportional, integral, and derivative gain) must be set to specific values to achieve the best controller response to setpoint and disturbance input changes. To minimize process variations and the response time to setpoint and disturbance input changes …

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Mar
04

Addressing Incorrect Tuning

DCS tuning Support

A Loop tuning has a significant impact on control loop utilization and performance. Controller tuning parameters can be easily changed over a wide range to adjust loop operation for various process requirements. However, some expertise in tuning is required even when advanced control tools are used, and there is a chance that the behavior of …

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Jan
14

Evaluating Control System Performance

Process Control System

The operation of industrial process control systems often involves the control of multiple unit operations with hundreds of measurements and control loops, as illustrated below. Although these systems are designed to automatically archive operational data in an historian, it is time consuming to examine historical data to determine if there has been a change in …

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Oct
22

Continuous Data Analytics – Impact of Transport Delay

Continuous Digester

When developing a PLS models for quality parameter prediction, the deviation of measurement values from their mean must be shifted in time to account for the time required for a change in the input to impact the quality parameter. Similarly, these delays should be taken into account in the processing of the deviation values used …

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Jun
18

Impact of ISA106 on Process Automation

One of the side discussions at the SC65E WG7 meeting in Meisdorf, Germany, May, 2012 was the work by ISA106 and its potential impact on process automation. The formation of the ISA106 committee was first announced by ISA in May, 2010. Since that time this committee has been very active. The purpose of this committe …

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Dec
05

Commissioning Highly Interactive Process

Commissioning Highly Interactive Process

At Emerson Exchange, 2011, I had the pleasure of working with Eric Chen, Research Associate, Pickle Research Center, University of Texas at Austin SRP and Willy Wojsznis, Senior Technologist, Emerson Process Management, to host a workshop that addresses commissioning of a skid process that is characterized by a high degree of process interaction. The size …

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