Algorithmic design and application of feedback control for coiling temperature in hot strip mill

Abstract

Microstructure and mechanical properties of hot-rolled strips are directly influenced by coiling temperature, and feedback control is one of the most significant approaches to improve coiling temperature control precision. Laminar cooling control system was introduced, and the novel feedback control algorithm based on proportional–integral controller and Smith predictor was designed, respectively, and the online adaptive algorithm was used to optimize parameters of proportional–integral controller. This control system has been successfully applied in a hot strip mill, and the record curves indicate that the novel feedback control system can get better dynamic characteristic. The coiling temperature can be precisely controlled with a high accuracy of ±15°C over 98.3%.