MULTIVARIABLE H_∞ FORCE/LEVEL CONTROL OF THE TWIN-ROLLER STRIP CASTER

摘要

Twin-roller steel strip casters may offer some advantages with respect to classical continuous casting hot rolling processes. Some works have reported control aspects of this process and, although the process has been found to be highly interactive and nonlinear, little or no attention has been given to its multivariable characteristics. The purpose of this work is to design a multivariable control capable of decoupling the system. This paper presents some important aspects of the strip caster modeling and reports the simulation results of the application of the multivariable H_∞-optimal control for nominal performance to force/level control. Various controllers have been designed for different pool level heights, and it is shown that they can decouple the system, allowing the application of PI decentralized controllers to considerably improve performance.