A2.2 Control Terminology and Fun

 定义文件

PCTP中SMOC控制器的定义文件是格式为“controller name. EXA”的文件。使用PCTP搭建的EXA文件将被加载到在线Exasmoc中以供使用。“控制器名称”最大限制为“非空格的”10个字符。整定参数被保存在Exasmoc引用的.EXA文件中。含有新保存整定参数的.EXA文件可以再次与PCTP一起使用。该文件可以在PCTP和Exasmoc之间互相使用。Exasmoc文件* .EXA是zip文件。所以当通过Exasmoc调度程序面板的append命令注册时，.EXA文件解压缩为* .CON和* DEF文件。

 位号名称

DCS位号名被用于定义文件。可用的位号名需要满足以下条件。
 位号名应该有一个'.'（点）特征字符。
 总位号名长度等于或小于64个字符。
 可用的字符是“大写字母”，“数字”，“ - ”（连字符），“_”（下划线）和“@”。
 使用调度程序面板上的清单功能检查DCS位号名。
 提供了一个工程工具用于处理其他特殊字符。请咨询横河电机工程办公室。

A2.2控制术语和功能

MV - 控制器通过计算操作变量动作，以将CV保持在设定值或限制范围内，并优化过程动态。控制器总是保证MV在限制范围内。可以将Exasmoc中的MV输出配置为DCS PID控制块中的设定点或直接输出。
例如在蒸馏过程中，顶部回流流量控制器（PID）设定值或所需的控制阀位为MV。
参见图2.1a“回流”流量控制器，以区分DCS控制器的MV和Exasmoc控制器的MV。
DV - 扰动变量是不受Exasmoc控制器控制的可测量变量，但它们影响控制器的CV。控制器的前馈预测动作可防止CV从设定的限制发生变化。
例如。在蒸馏过程中，典型的DV是进料速率，进料温度和进料质量。
POV - 过程输出变量包括被控变量和中间变量。
例如。在蒸馏过程中，顶部产品质量是被控变量（由Exasmoc直接控制），另一方面，顶部塔盘温度是不被Exasmoc直接控制的中间变量。
CV – 被控变量是必须保持在某个值或限制范围内的过程变量，并且是需要优化的过程变量。 CV由控制器输入，可以是测量值或计算值。
例如，塔顶产品质量是蒸馏过程中的CV。
EF - 经济函数是要优化的过程函数。经济功能和经济系数定义优化目标。
EFs仅在Exasmoc控制器的优化操作模式下有效。 EF的优化功能将
在下一节进一步说明。

原文：

 Definition file

The definition file of the SMOC controller with PCTP is made as a “controller name. EXA “file. EXA file made with PCTP to be loaded in Online Exasmoc for use. The “controller name” is limited to be ‘non-space’ 10 characters at maximum. The tuning parameters are saved in the .EXA file referred in Exasmoc. The .EXA file with new saved tuning parameter can be used with PCTP again. This file can be mutually used between PCTP and Exasmoc online. Exasmoc file *.EXA is the zip file. So when registered by the use of the append command of the Exasmoc scheduler panel, .EXA file is unzipped to *.CON and *DEF file.

 Tag name

DCS tag name is used in the definition file. Available tag name are restricted to satisfy the following items.
 Tag name should have a ‘.’ (dot) character.*
 Total tag name length is equal or less than 64 characters.
 Available character is ‘capital alphabet ’, ‘numerical’ ,‘-‘ (hyphen), ‘_’ (underscore) and ‘@’.
 DCS tag name is checked using the checklist function on the scheduler panel.
 For other special character, an engineering tool is provided. Please consult with Yokogawa engineering office.

A2.2 Control Terminology and Functionality

MV – The controller computes Manipulated Variables to keep the CV’s at setpoint or within limit and to optimize the process behavior. The controller always keeps the MV’s within their limits. The MV output from Exasmoc can be configured to go on to any set point or directly output control connection of a DCS PID controller block.
e.g. In a distillation process Top Reflux Flow Controller (PID) Setpoint or desired control valve position is MV.
Refer Figure 2.1a “Reflux” Flow Controller for distinguishing MV of DCS Controller and MV of Exasmoc Controller.
DV – Disturbance variables are measured variables not under the control of Exasmoc controller but they affect the CV’s of the controller. The feed forward predictive action of the controller prevents the CV’s to be changed from the set limits.
E.g. In a distillation process typical DV’s are feed rate, feed temperature and feed quality.
POV – Process Output Variables are those, which includes Controlled Variables and Intermediate variables.
E.g. In a distillation process product top quality is a Controlled Variable (which is directly controlled by Exasmoc), on other hand top tray temperature is an intermediate variable not directly controlled by Exasmoc.
CV – Controlled Variables are the Process variables that must be maintained at some value or within limits, and/or are to be optimized. CV’s are input by the controller and may be measured or calculated values.
E.g. Top product Quality is the CV in a distillation process.
EF – Economic Functions are process function to be optimized. Economic Functions and Economic Coefficients define targets for optimization.
EFs are effective only during Exasmoc controller’s optimization mode of operation. EF is further explained in the following section along with optimization function.

2017.3.26