Robust Gauge Control for Hot Finishing Mills

Abstract

A new gauge control system for hot finishing mills has been developed to distribute the mill motor power of each stand. The new system has the following features :
(a) Interstand exit gauge is calculated based on the law of mass flow constancy using the exit thickness gauge. (b) The design strategy of the new system are to cope with a detection time delay, and to simplify the controller to easily tune during actual implementation. (c) The H_∞, controller with two degrees of freedom is designed to obtain high responses of the reference and disturbance. The performance of the controller is evaluated by numerical simulation. The effectiveness of the new system has been shown by application in an actual plant.