Control of supersaturation in batch cooling crystallization by robust state feedback linearization

This paper discusses control of seeded batch cooling crystallizers by supersaturation tracking control. Batch crystallization is characterized by nonlinear behavior throughout the complete batch period. In this paper, state feedback linearization is used to create a linear input-output mapping for the absolute supersaturation. It is shown that by implementation of a nominal state feedback law, the nonlinear model can be represented by an uncertain linear model with an input disturbance. This method can be used to account for parametric model uncertainty in the design of a robust ℋ_∞-controller. Simulation results of control with an ℋ_∞-controller and a Model Predictive Controller (MPC) in combination with state feedback linearization reported.