Tag Archive: performance

Feb
24

Wireless Control – ACC 2014

The 2014 American Control Conference, ACC, will be held Wednesday through Friday, June 4 – 6, at the Hilton Portland & Executive Tower, Portland, OR. As noted on the conference web site, the ACC is internationally recognized as a premier scientific and engineering conference dedicated to the advancement of control theory and practice. Last year …

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Nov
04

Utilizing DeltaV Advanced Control Innovations

Utilizing DeltaV Innovations

Several Meet the Expects workshops are schedule on the last day of Emerson Exchange. As part of this effort, Willy Wojsznis and I co-hosted a workshop this year titled Utilizing DeltaV Advanced Control Innovations to Improve Control Performance. In this workshop we explore and discuss innovative features of the DeltaV PID and embedded Advanced Control …

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Oct
07

Addressing Control in the Presence of Process and Measurement Noise

Application of Kalman Filter in DeltaV

When a measurement used in a control application is characterized by a significant amount of process or measurement noise then to avoid taking control action on noise filtering may be applied in the transmitter or in the control system. However, when traditional filtering techniques are used it is necessary to increase the PID reset time …

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Sep
09

Control Using Wireless Measurements

Kalman Filter In Wireless Control

A number of technical challenges must be addressed when using a wireless measurement in closed loop control. In DeltaV v11 we introduced a PID option known as PIDPlus that may be selected when a wireless transmitter is used in a control application. When the PIDPlus option is selected then the same quality control as wired …

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Aug
19

Fuzzy Logic Control – Example

Process for Fuzzy Logic Workshop

In this fuzzy logic control workshop contained in Chapter 6 of Advanced Control Foundation – Tools, Techniques, and Applications, the control performance of fuzzy logic control is be compared to the performance of PID control. For this example, the control objective is to reach setpoint in minimum time with no overshoot. Two identical process heaters …

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Aug
12

Fuzzy Logic Control – Commissioning

Tuner Interface for Fuzzy Logic Control

To allow consistent implementation of control applications, fuzzy logic control may be implemented as a function block. The fuzzy rules and membership functions can be predefined except for the scaling of the membership functions for error, change in error, and change in output.  As addressed in Chapter 6 of Advanced Control Foundation – Tools, Techniques, …

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Aug
05

Fuzzy Logic Control – Implementation

Predefined Fuzzy Logic Control Function Block

To minimize the time needed to apply fuzzy logic control, most manufacturers offer a version of fuzzy logic control in which the rules and membership functions are pre-defined. As described in Chapter 6 of Advanced Control Foundation – Tools, Techniques, and Applications, , a manufacturer can provide support for auto-tuning by restricting the fuzzy logic …

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Jul
08

Adaptive Tuning – Models Identified

Viewing Identified Models

The basis of adaptive tuning is the identification of the process step response based on operator changes in the loop operation. For example, when a control loop is in Automatic mode, changes made in the setpoint can trigger process model identification. If the loop mode has been changed to Manual, then changes by the operator …

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Jul
01

Adaptive Tuning – Model Switching

Adaptive PID Controller With Model Switching and Parameter Interpolation

During the development of the DeltaV adaptive tuning capability, we researched and evaluated many of the most common techniques for implementing adaptive tuning. Also, as part of this research we came across a number of technical articles on a relative new adaptive tuning technique known as model switching. This technique depends on the evaluation of …

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Apr
09

Performance Monitoring Tools

Performance Monitoring Overview

Many control system manufacturers and third party companies now offer tools that are designed to monitor process control and instrumentation performance. In addition to providing on-line information that summarizes control utilization, the user may access other information that may be helpful in determining the cause of, and solution to, poor control utilization. In section 3.4 …

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