Robust controller design for batch polymerization reactors

This paper discusses several robust controller design methods for the batch polymerization reactors. The dynamic characteristics of batch polymerization reactors considerably change according to the progress of reaction because the reactors have strong nonlinearity. The reactor models have parameter uncertainty. On the other hand, both reactor temperature control and polymer quality control are important specifications for batch polymerization. In this paper we propose robust controllers which are designed to satisfy the above specifications. The controllers are composed of a feedforward controller based on a nonlinear process model and a H^∞ feedback controller based on linearized models along optimal trajectories. Moreover, the H^∞ controller is designed to be robust to the dynamics change caused by both nonlinearity and parameter uncertainty. The effectiveness of our control strategy is illustrated by simulation study.