Comparison of bilinear and PID control on a test furnace at British Steel

This paper details the findings of a comparative study when a single-input single-output bilinear self-tuning controller, which has been developed by the Control Theory and Applications Centre of Coventry University, is applied to a re-heat furnace at British Steel, Swinden Technology Centre, Moorgate, Rotherham. The performance of the bilinear self-tuner is compared to that of an industry standard PID controller which had been previously tuned manually to achieve optimum performance. Whilst the performances of the two schemes are not dissimilar the bilinear approach with its online tuning facilities offers potential advantages over existing commercially available automatic loop tuning devices It is recommended that the bilinear controller should be further developed and extensively evaluated under demonstrator and real-time plant trials on continuously operated furnaces.