화학공학소재연구정보센터
Journal of Process Control, Vol.22, No.9, 1800-1819, 2012
Compensation of control valve stiction through controller tuning
Despite numerous studies on modeling and detection of static friction (stiction) in control valves, compensation methods for this problem are limited. In this work, a stiction compensation framework is proposed which is based on the oscillation condition introduced in [17]. This condition was used as a tool to predict occurrence and severity of stiction-induced oscillations in control systems. The aim of this paper is to suggest re-tuning guidelines for controllers with regard to the presence of stiction in the control valve, to eliminate or reduce oscillations. A variety of processes and controllers are studied and recommendations are made in order to eliminate the stiction-induced oscillations. For oscillations that cannot be removed, the proposed method will reduce the frequency and magnitude of oscillations. This compensation framework has also been validated using two different pilot-scale experiments with different types of processes and an industrial control system. (C) 2012 Elsevier Ltd. All rights reserved.