Speed disturbance compenation in the secondary cooling zone in continuous casting

The continuous casting process is used for the solidification of molten ste el into semi-finished shapes. Several factors influence the quality of cast steel, including mould level oscillation and cooling patterns in the secon dary cooling zone. This article presents a dynamic model that can be used t o study heat transfer in the continuous casting process. Temperature measur ements in the secondary cooling zone are infeasible due to the effects of s cale and steam on the measurement equipment. Two different feedforward cont rollers are proposed and compared to eliminate the effects of varying casti ng speed on the strand temperature; thus reducing the defects in the finish ed product. The first controller is based on typical controllers found in p ractice and a design methodology is proposed for the design of this control ler The second controller has dynamic properties and makes full use of the plant and disturbance transfer functions in its design. It is shown that di sturbance rejection of the second controller is better than that of the fir st controller.