A Thickness Control Method for Hot Continuous Rolling Based on Improved Internal Model Controller

Abstract

The invention relates to a hot continuous rolling thickness control method based on an improved internal mold controller. The method comprises the steps that a mathematical model of a machine frame hydraulic roll gap control system (HGC) is established, and the HGC system model is identified through a particle swarm optimization algorithm (PSO); a traditional internal model monitoring AGC controller is designed based on the model, and the traditional internal model monitoring AGC controller is improved into a two-degree-of-freedom controller; and an iterative learning algorithm is introduced into a monitoring AGC system based on the improved internal model controller. The iterative learning algorithm can make full use of historical cycle information of the monitoring AGC system, and modifythe control quantity of the internal model monitoring AGC system through a certain learning law, so that the monitoring AGC system automatically adapt to the model parameter mismatch condition duringhot continuous rolling. According to the technical scheme provided by the embodiments of the present invention, the control quality and robustness of the hot continuous rolling monitoring AGC systemcan be improved.

Description

technical field [0001] The invention relates to the new technology field of hot continuous rolling processing of iron and steel plates, in particular to a method for controlling the thickness of hot continuous rolling based on an improved internal model controller. Background technique [0002] Thickness accuracy is an important index for assessing the quality of strips. Automatic thickness control technology (AGC), as the most important means to improve the thickness accuracy of strip products, has become an indispensable and important component in modern hot strip production. part. The monitoring AGC is based on the closed-loop control of the thickness of the rack outlet by the thickness gauge on the outlet side of the final rack, so the monitoring AGC ensures that the thickness of the finished product is consistent with the target thickness in terms of trend. Therefore, the monitoring AGC is irreplaceable compared with other types of AGC, but due to the installation posi...

AI Technical Summary

Problems solved by technology

Therefore, the monitoring AGC is irreplaceable compared with other types of AGC, but due to the installation position of the thickness gauge on the outlet side of the final frame, there is a certain lag time in the detection of the outlet thickness, so that there is a pure lag in the control closed loop of the monitoring AGC link, which in turn degrades the performance of the monitoring AGC

Especially as the pure lag time becomes larger, the robustness of the system will become worse and worse, and may cause system instability

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