Design of Auto-tuning Relay Feedback controller for Shell Heavy Oil Fractionator

Abstract

Auto-tuning relay feedback is one of the control techniques, which is used to solve the non-linear, long delay time, and disturbance's problems. This control technique is the development of Ziegler-Nichols that can be done automatically without doing system modeling. In this paper, auto-tuning relay feedback is used in the control system response to optimization of Shell Heavy Oil Fractionator (SHOF) system so the output of product composition as expected. SHOF is a distillation column type used to separate crude oil into desired products based on the difference in the boiling point of each product. PI regulators of relay feedback are used to control the valves on the SHOF with three inputs and three outputs that has been decoupled. Based on the tests, the average values of IAE at top end point composition (Y1) obtained with disturbance and no disturbance are 83.17 and 10.933, respectively. At the side end point composition (Y2), the average values of IAE with disturbance and no disturbance are obtained respectively, 336.38 and 42.3467. The average values of IAE at bottom reflux temperature (Y3) with disturbance and no disturbance are obtained 0.15 and 0.13, respectively.