Multi-resolution hardness feed-forward automatic gauge control for hot-rolling mill based on wavelets

In hot-rolling process, the hardness (temperature) variations of entry strip is the major factor effecting final thickness, however it is not easy to counteract using conventional automatic gauge control (AGC) method. This paper presents a novel hardness feed-forward automatic gauge control method based on multi-resolution decomposition using wavelets (MR-HFF-AGC), the roll force of F1 stand are decomposed into signals at different scales using wavelets, then signals containing hardness information is converted into control decisions used for feed-forward control in latter stands. The performance improvement of MR-HFF-AGC method is shown via the simulation using the real coil data.