液压弯辊控制系统的建模及辨识

通过分析液压弯辊控制系统的结构,给出了系统各个环节的传递函数,建立了液压弯辊控制系统的传递函数.针对理论模型中参数难以确定的问题,以某四辊冷轧机为对象设计了系统辨识方案,采用自回归历遍(auto regressive exogenous,ARX)模型辨识出液压弯辊控制系统模型.辨识的输入和输出数据分别为弯辊闭环系统的弯辊油压给定值和弯辊油压实际值,模型参数估计采用最小二乘法.通过残差分析检验了模型的有效性,结果表明:辨识模型的输出响应能很好地反映实际系统的动态输出特性,并具有较高的精度,证明ARX辨识算法对于弯辊系统的辨识是可行的.

Modeling and Identification of Hydraulic Bending Roll Control System

Based on the analysis of a hydraulic bending roll control system,a transfer function of every link in the system was constructed,and then a theoretical model of the whole control system was established.In view of the difficulty in determining theoretical model parameters,a system identification method for a four-high mill was presented,with an accurate model of bending roll control system achieved using ARX(auto regressive exogenous) model.In the hydraulic bending roll closed-loop control system,an oil pressure setting and actual oil pressure were respectively used as the system’s input and output,and the model parameters were estimated by least squares estimation method.The results showed that the output response of the identification model can reflect the dynamic characteristics of actual system well,which proves the feasibility of the ARX identification method for bending roll control system.