基于波函数模型的设限频域前馈板厚控制研究

The plate production is accounting for half of the number of total steel production and the thickness precision is one of the most important quality indexes of cold rolling strip. To improve automatic gauge control (AGC) technique is the thesis and research focus which urgently need to be solved. The feed-forward AGC has already been confronted by the bottleneck of the model problem ,the antinoise problem is one of the difficulties of the feed-forward AGC technique. In this project,the main research contents and innovations include:(1)The model problem will be solved by establishing the expression of the wave-function model of thickness location in rolling process and driving its solving algorithm to achieve a complete description of thickness location in rolling process in the form of wave-function, which obtain time and space two-dimensional mapping of strip thickness.(2)Based on the foundation that the model problem have been solved ,according to two class parameters including frequency stationarity and wavelength stationarity in rolling process,the expression patterns of the sphere of action of the frequency domain is extended ,which introduce the concept of wavelength type(λ-type) on the basis of the frequency type (f-type);the traditional feed-forward AGC is improved throuth restricting the frequency domain of the feed-forward AGC,so as to solve the antinoise problem.The mathematical model of thickness location in rolling process which is complete and easy to analyze is expected to set up and the new algorithm of the feed-forward AGC which has better performance is expected to be obtained by the study in this project. The study will provide a new way to increase thickness precision and has important practical value and academic significance to solve similar technical problems.

板带产品占钢材总量之半，厚度精度是冷轧带钢最重要的质量指标之一，改进板厚控制技术是迫切需要解决的课题和研究热点。模型问题是制约前馈板厚控制技术发展的瓶颈，抗噪问题是前馈板厚控制技术的难点。本项目主要研究内容及创新点为：（1）通过建立轧制过程厚度定位波函数模型表达式并推导其求解算法，实现以波函数形式完整地描述轧制过程厚度定位，即获得带钢厚度时空二维映射，从而解决模型问题。（2）在解决模型问题的基础上，针对轧制过程包含频率平稳性和波长平稳性两类参数，扩展频域作用范围表达类型，即在频率型（f型）基础上引入波长型（λ型）表达；通过对前馈板厚控制频域设限，实现对传统前馈板厚控制算法的改进，从而解决抗噪问题。通过本项目的研究可望建立便于数学分析和处理的完整的轧制过程厚度定位数学模型，获得性能更佳的新型前馈板厚控制算法，为提高板厚控制精度提供新途径，对解决类似工程技术难题具有重要理论意义和实际价值。

板带产品占钢材总量之半，厚度精度是冷轧带钢最重要的质量指标之一，改进板厚控制技术是迫切需要解决的课题和研究热点，轧制过程厚度模型是制约板厚控制技术发展的瓶颈。. 首先建立了轧制过程厚度波函数模型的偏微分方程，该表达能够描述轧制变速与变形时厚度信息。由轧制过程厚度波函数偏微分方程推导得到其变换属性、求解算法及解的存在区域。采用云图实现了对轧制过程波函数的几何描述，由此创建了基于波函数的多观测线分析法，能够简化轧机变速时的厚度信息处理。. 针对轧机板厚多环路控制系统控制器投切转换时出现的扰动冲击，首先构造范数以量化切换冲击，再以切换冲击范数为目标函数，构造了切换频域设限算子，并构建了设限频域控制策略，可有效减小多环路控制系统控制器的切换冲击。相较于传统滤波器，其优点在于兼顾了信号相位偏移。. 波函数模型和设限频域控制策略在轧机秒流量控制和轧辊偏心补偿控制等系统中获得了成功应用。采用轧制过程厚度波函数模型实现轧机厚度精准定位和秒流量计算模型的优化，提高了秒流量厚度计算精度，并通过设限频域控制策略改进了秒流量控制器的投切性能。采用波函数模型亦可简化在变速情况下对轧辊偏心信号的提取与处理，从而提高轧辊偏心补偿系统性能。. 波函数模型的实质在于在较高维空间中简化数据分析与处理。因此，波函数模型可在针对具有变速特性的平移或旋转系统的分析与设计领域得到很好应用。设限频域控制策略的实质是通过各控制器控制量的正交化（或准正交化），实现在不降低控制性能的前提下减小控制器投切或转换时的冲击扰动。因此，设限频域控制策略可在多环路控制系统中得到很好应用。. 通过基于增益辨识的动态保性能控制策略有效减小了材质硬度不确定性对板厚精度的影响。通过基于观测的状态反馈条件下的控制器优化提高轧机液压伺服系统动态性能满足了系统改进后高响应的需求。. 对上述控制算法和策略开发了应用软件，在生产轧机运行中取得了良好效果。