On the reheat furnace control problem

This paper develops a model and control algorithm for the temperature control of steel blocks (slabs) passing through a furnace burner zone. The slab temperature is controlled by varying the zone temperature. A model for a single slab passing through the furnace is developed and the parameters of this model are estimated. Data from the reheat furnace no. 2 at The Danish Steel Work Ltd. are used for the identification. The single slab model is used for building a model for all slabs in the burner zone. A slab temperature reference function (heating curve) is found from the slab temperature model. A nonlinear controller is designed to minimize the deviation from this heating curve. The stability and controllability of the system is also analyzed