A Model Free Approach for Online Stiction Compensation
نویسندگان
چکیده
Stiction is one of the most adverse non-linearities that can affect a control valve. It impacts both valve longevity and product quality. Currently available stiction compensation methods either reduce the amplitude of oscillation at a cost of increased frequency or require knowledge about process and valve models. In this study a novel stiction compensation scheme is developed which reduces both oscillation amplitude and frequency, obtains good set point tracking and disturbance rejection, and yet requires minimal information about the process and is simple-to-implement online. The method has been successfully evaluated on a pilot plant interfaced to a commercial DCS system.
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