Robust Control of a Distillation Column

Abstract

AbstractIn this chapter we present the design of a robust control system for a high-purity distillation column. The original nonlinear model of the column is of high order and it includes parametric gain and time-delay uncertainty. A low-order linearized distillation column model is used in the design of a 1-degree-of-freedom \(\mathcal{H}_{\infty}\) loop-shaping controller and a 2-degree-of-freedom (2DOF) μ-controller. Both controllers ensure robust stability of the closed-loop system and fulfillment of a mixture of time-domain and frequency-domain specifications. A reduced order μ-controller is then found that preserves the robust stability and robust performance of the closed-loop system. The simulation of the closed-loop system with the nonlinear distillation column model shows very good performance for different reference and disturbance signals as well as for different values of the uncertain parameters.KeywordsRobust StabilityDistillation ColumnLiquid HoldupTransfer Function MatrixComplementary Sensitivity FunctionThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.