A New Method to Compensate the Zero Drift of HGC System for Rolling Mills

摘要

HGC (hydraulic gap control) is the kernel module in an AGC (automatic gauge control) precision of HGC system. Adopting a PI controller to compensate the drift will decrease the response speed of the system, which is not conducive to last adjusting of AGC. In this article, a. dynamic compensation method is developed to solve this problem, which identify and compensate the aero drift by studying the control valve change of HGC and the pressure change between servo valves. Simulations show that the precision of HGC system has been improved greatly by this method, without decreasing the response speed of the system. This method is successfully applied in a 550 mm hot rolling mill in Taiyuan Iron & Steel (group) Co. LTD of China.