A Multivariable and Multi-Objective Approach for the Control of Hot-Strip Mills

Abstract

The control of a hot strip rolling mill is quite a complex problem due to the presence of many simultaneous control tasks. This is the main motivation that spurred the major steel corporations to adopt more sophisticated control techniques based on multi-variable concepts. The main drawback of most multi-variable approaches is the lack of transparency of the resulting controller that, consequently, can turn out hard to tune on site. In this paper we solve the tuning problem by adopting a multi-objective control approach that allows explicitly taking into account the existence of actuator limitations and nonlinear dynamics. Furthermore, the application of the proposed control technique to a narrow hot strip mill is here described.