美文网首页PCTP
Building a Process Model-Using t

Building a Process Model-Using t

作者: 橡果 | 来源:发表于2016-09-04 19:52 被阅读12次

    Import Most Recent(导入最新)按钮让应用程序忽略来源导入最新的传递函数。
    左下角的下拉菜单列表用于根据需要导入变量选择导入描述的具体行为。
    Ignore Descriptions(忽略描述) 不导入描述。
    Import Descriptions(导入描述) 当在预先存在模型里描述为空时选择导入描述。
    Overwrite Descriptions(覆盖描述) 始终导入描述,若有需要将覆盖预先存在模型的描述。
    单击Finish按钮后,将显示导入过程状态。如果成功完成导入过程,对话框显示消息“Import Complete. Do you wish to see the import log?(导入完成,你是否希望查看导入日志?)”。单击Yes按钮显示导入日志文件,否则单击No继续。


    如果你选择显示日志文件,包含在AIDAPro文件中的每个选中导入输入输出传递函数都将得到显示。若在导入过程中遇到任何问题,他们也会显示。


    导入过程完成后,用户可以使用图形模型构建器方便地工作。可用选项包括:
    •编译 - 提供模型检查和编译,即不可测量扰动的输入以及适合仿真生产的模型展示。
    •曲线 - 显示了模型输入到输出动态的脉冲/阶跃响应曲线。
    •分析 - 介绍了模型的操作和测量干扰输入与模型输出之间的增益矩阵。
    •报告 – 详细描述了模型传递函数的类型,参数及相应的连接,使得生成的报告足以重新绘制整个模型。
    在模型搭建时使用变换
    工厂本身是非线性的。然而在许多情况下,工厂可以在其操作点根据合适的变换线性化。例如,对输入和输出变量使用对数变换可使得在转换坐标后工厂行为变为线性。在仅作输入变换的情况下(下图的输入变换),MVs/DVs都是变换后的坐标,SMOCPro中标识的模型的POV都是工程单位,而MV/DV是变换后坐标。在当前输入和输出都作变换的情况下(下图的输入—输出变换),SMOCPro中辨识模型的POV和MV/DV都处于变换坐标下。
    为进行转换,SMOCPro提供了一个工具选择分段线性变换(查找表)。当输入在范围内时,变换将在两个连续点之间进行线性内插,当输入在范围外时,变换将进行最后两个点的外推。从理论上说,如果点的数目足够大,分段线性变换可以模仿任何函数。

    原文:
    The Import Most Recent button lets the application import the most recent transfer functions regardless of their origin.
    The drop-down menu list at the bottom left hand corner is used to choose specific actions for importing the descriptions of the variables to be imported.
    Ignore Descriptions Do not import descriptions.
    Import Descriptions Import descriptions when the descriptions in the pre-existing model are empty.
    Overwrite Descriptions Always import descriptions anyway, overwriting the pre-existing description when necessary.
    After clicking on the Finish button, the import process status is displayed. If the import process finished successfully, a dialog box displays the message “Import Complete. Do you wish to see the import log?” click the Yes button to display the Import Log file, otherwise click No to continue.
    If you have chosen to display the log file, all the input-to-output transfer functions contained in each of the AIDAPro files selected-for-import are displayed. If there were any problems encountered during the import process, they are also displayed.
    After the import process has been completed, the user can easily work with the model using the graphical model builder. The available options include:
    •Compile – Provides model checking and compilation, i.e. incorporation of unmeasured disturbance inputs and production of the model representation suited for simulation.
    • Plot – Shows the impulse/step response plots of the model input-to-output dynamics.
    • Analysis – Presents the gain matrix between the model’s manipulated and measured disturbance inputs, and the model’s outputs.
    • Report – Details the model’s transfer functions types, their parameters and the corresponding connections so that the resulting report is sufficient to re-draw the whole model at once.
    Using transforms for model building
    Plants are inherently nonlinear. However, in many cases, the plant can be linearized about its operating point by a suitable transform. For example, a logarithmic transform can be applied to the input and output variables such that in the transformed coordinates the plant behavior is linear. In the case of only input transform (Figure Input Transfer below), the MVs/DVs are in the transformed coordinates and the identified model in SMOCPro is between the POV in Engineering Units and the MV/DV in Transformed coordinates. In case where both input and output transforms are present (Figure Input-Output Transform below), the identified model in SMOCPro is between the POV in Transformed coordinates and the MV/DV also in Transformed coordinates.
    To carry out the transforms, SMOCPro provides a tool with the option of piecewise linear transform (lookup table). This transform linearly interpolates between two consecutive points when the input is in the range or linearly extrapolates the last two points when the input is out of the range. Theoretically, piecewise linear transform can mimic any function if the number of the points is sufficiently large.


    2016.9.4

    相关文章

      网友评论

        本文标题:Building a Process Model-Using t

        本文链接:https://www.haomeiwen.com/subject/bsnlettx.html