The paper reviews adaptive tuning techniques which have been implemented in commercial controllers, and successfully applied to a variety of industrial processes. Some characteristics of industrial processes which cause problems for adaptive tuners are discussed, together with solutions to these prablems.
Gain-scheduling is shown to be a useful alternative to continuously adaptive techniques where robustness is required with changing plant conditions. The closed-loop cycling method is discussed both as an independent auto-tuning technique, and as a pre-tune for parameterising continuously adaptive tuners. The strengths and weaknesses of waveform analysis techniques and model-based predictive controllers are highlighted.
A novel self-tuning output algorithm for driving motorised valves is proposed as a solution to problems encountered in controlling processes using these actuators.
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