Design of Feedforward-Feedback Controller for Reactive Distillation Column having Inverse Response

Inverse response occurs due to the two opposing processes working at the same time. This inverse response can occur because of a step change either in a load variable or a manipulated variable. In this paper inverse response due to a load variable is considered for a reactive distillation column carrying an esterification reaction. A feedforward-feedback controller is designed to eliminate the effect of inverse response in the process. The results showed a decrease in sluggishness and integral errors while using a feedforward-feedback controller instead of a feedback controller in the closed loop.