Tag Archive: filtering

Oct
07

Addressing Control in the Presence of Process and Measurement Noise

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
16

Application of the Kalman Filter in Process Control

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 uses a dynamics model, measured control input(s) and process measurement(s) to estimate the process output. A wide variety of applications have successfully utilized Kalman filtering:  The guidance of …

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Jun
10

Application of Kalman Filtering in DeltaV

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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Jul
11

Commissioning Control Systems – Input Filtering

The method used to process analog inputs and outputs is unique to each control system.  Also, controller and IO bus design influence how often measurement and outputs are updated and thus dictate the control execution rate that is supported by the control system. Understanding the limitations imposed by the basic control system design (i.e., controller …

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Oct
14

Guidelines for Setting Filtering and Module Execution Rate

Many digital controllers used in the process industry today allow the end user to specify the control loop period of execution. However, books on process control often provide little or no information on how execution period impacts control performance. Also, no mention is made of the fact that the amount of filtering needed to avoid …

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