Abstract
This report discusses the development of promising system control technologies which have been mainly applied to thickness control after late 70 mainly. In the late 1970 s, modern control theory and optimization technique were introduced into the field of thickness control in earnest and they greatly contributed to the quantitative expansion of the domestic steel industry. As the examples, the AGC gain by optimum regulator theory and thickness and inter stands tension control system by multivariable control technique are shown.
After the 90 s, the high added value and function improvements of the control system become more and more important for steel industry including the thickness control and they were indispensable for manufacturing of the high-strength steel. Here, the mill balance control for the tandem cold mill and the highly precise rolling load model by Genetic Programming are explained.
As future problems, it is mentioned that practical use of the operation know-how is important and the development of the operation support system using them is significant.
