Abstract
Oscillations in process control loops are a very common problem. Oscillations often indicate a more severe problem than irregular variability. The presence of oscillations in a control loop increases the deviations from the setpoint of the process variables, thus causing inferior products, larger rejection rates, increased energy consumption and reduced average throughput. There are several reasons for oscillations in control loops. They may be caused by excessively high controller gains, oscillating disturbances or interactions, but a very common reason for oscillations is friction in control valves. Detection and diagnosis of oscillatory behaviour in a production process is of importance because process variability has an impact on profit. In the context of performance assessment and troubleshooting, the objectives of oscillation diagnostics of control loops can be stated as to i) identify sustained oscillations in a control loop, and ii) distinctly detect and quantify the root-cause(s) once the loop is confirmed to be oscillatory. In this chapter, the methods that are present in the literature to identify oscillations in process variables are discussed in detail. Their applicability to industrial control-loop diagnosis is critically evaluated on various simulation and industrial case studies.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2010 Springer-Verlag London Limited
About this chapter
Cite this chapter
Karra, S., Jelali, M., Karim, M., Horch, A. (2010). Detection of Oscillating Control Loops. In: Jelali, M., Huang, B. (eds) Detection and Diagnosis of Stiction in Control Loops. Advances in Industrial Control. Springer, London. https://doi.org/10.1007/978-1-84882-775-2_4
Download citation
DOI: https://doi.org/10.1007/978-1-84882-775-2_4
Publisher Name: Springer, London
Print ISBN: 978-1-84882-774-5
Online ISBN: 978-1-84882-775-2
eBook Packages: EngineeringEngineering (R0)