面向远程仿真的电阻炉建模研究

Modeling of Electric Resistance Furnace in a Remote Simulation and Control Laboratory

实验对象模型的建立是远程仿真系统中极其重要的部分,研究了电阻炉远程仿真与控制实验室系统中远程仿真模块的电阻炉建模方案,分析了远程仿真系统与一般工业过程控制中建模需求的区别,探讨了系统的远程特性赋予建模工作的新的特点.根据实验设备的结构和远程特性设计了建模实验,在尝试并比较了多种建模方案及模型结构之后,提出采用多项式拟合方法获得电阻炉针对远程仿真的二阶模型.为验证仿真模型的有效性,将PID控制典型情况下的实时控制曲线与不同阶次、不同结构模型的仿真曲线进行比较.结果表明,采用多项式拟合方法获得的二阶模型与实时控制曲线最一致,能反映电阻炉控制系统的动态特性,并提出了采用插值方法进一步完善仿真模型的设计方案.

Modeling plays an important role in a remote simulation system.A modeling scheme for electric resistance furnace in a remote simulation and control laboratory is investigated in this paper.There exist some differences in modeling requirement between remote simulation systems and general industrial process control systems.Remote control brings more characteristics to the modeling.An experiment is designed to collect proper data for identification and eliminate some difficulties that may arise during modeling.After attempts and comparisons of several modeling methods and model structures,two-order simulation model is obtained using polynomial fitting method.In order to verify the model,actual control results of typical cases of PID control and simulation results of several models with different orders or structures are compared,which proves that the two-order model produced by polynomial fitting method fits characteristics of the furnace control system best.Finally,further improvement method for simulation model with interpolation is presented.