Conventional Proportional–Integral (PI) Control of Dividing Wall Distillation Columns: Systematic Tuning

This work addresses the systematic tuning of proportional–integral (PI) controllers for dividing wall distillation columns. By following an approach of stable pole assignment to a linear dynamics that approximately describes the control system convergence, a technique results that forces the gains of controllers to be dependent on well-known parameters for each control loop: a static gain and a time constant that characterize the open-loop response of the output with respect to the control input, and a damping factor and a response velocity that outline the path of the closed-loop response. Then, it becomes possible to tune all the controllers in a simultaneous way, substantially reducing trial-and-error activities on tuning the entire control system. Via simulation, the control system performance is illustrated for disturbance rejection and set-point tracking in a representative dividing wall distillation column, showing that this tuning technique is an effective choice.