FREQUENCY-DEPENDENT DISTRIBUTION OF MANIPULATED VARIABLES FOR CHANGING THE ROLLED STRIP CROSS SECTION IN A ROLLING MILL

摘要

A rolling stock (2) made of metal is rolled in roll stands (3a to 3f) of a rolling train (1). Due to a variable (δQ) that is characteristic of the change in the cross-section with which the rolling stock (2) is to run out of a specific roll stand (3e) of the rolling train (1), for this roll stand (3e) and upstream roll stands (3b to 3d ) first provisional manipulated variables (Sb to Se) and, with their utilization, final manipulated variables (Sb 'to Se') that influence the cross-section with which the rolling stock (2) runs out of the respective roll stand (3b to 3e). The roll stands (3b to 3e) are controlled accordingly. The preliminary manipulated variables (Sb to Sd) for the upstream roll stands (3b to 3d) are determined by frequency filtering the characteristic variable (δQ) or a respective intermediate variable (Zb to Zd) determined therefrom. The frequency filterings are designed in such a way that only frequency components of the characteristic variable (δQ) that are below a respective limit frequency (fb to fd) are included in the determination of the respective preliminary manipulated variable (Sb to Sd). The cut-off frequency (fb to fd) remains the same or increases from roll stand (3b to 3d) to roll stand (3b to 3e). The preliminary manipulated variable (Se) for the specific roll stand (3e) is determined in such a way that at least those frequency components of the characteristic variable (δQ) are included in its determination that are above the cutoff frequency (fd) of the roll stand (3e) immediately upstream of the specific roll stand (3e). 3d) lie.