Atmosphere Dynamics Modeling and Hydrogen Ratio Control of Horizontal Continuous Annealing Furnace

Abstract

This paper is concerned with the hydrogen ratio control in a horizontal continuous annealing furnace used in steelmaking. We first model the nonlinear dynamics of the atmosphere in the furnace so that the hydrogen ratio control may be carried out by applying control theory. We then determine an appropriate equilibrium around which its linearized model is determined. We then take a two-step procedure for designing a linear controller, in which we first apply a minor feedback loop for pressure control and then apply integral compensation so that the hydrogen ratio tracks the reference input without any steady state error. The effectiveness of the resulting controller is verified through a simulation with the original nonlinear model of the furnace.