基于PLC的小型高精度多相流实验装置测控系统设计  

Design of measurement and control system of experimental apparatus for PLC-based small high-precision multiphase flow

作　　者：李小亭[1] 张琛[1] 方立德[1] 张垚[1] 梁玉娇[1] 何青[1] 

机构地区：[1]河北大学质量技术监督学院,保定071002

出　　处：《电子测量与仪器学报》2014年第6期670-674,共5页Journal of Electronic Measurement and Instrumentation

基　　金：国家自然基金(61074174;61340028);河北省自然基金(F2011201040);河北省教育部重点项目(ZH2012064)资助

摘　　要：设计了1套小型高精度油气水三相流实验装置,重点讨论该装置的测控系统设计及实现。通过比较可编程控制器(programmable logic controller,PLC)以及单片机测控系统的特性,选择PLC为基础构件测控系统硬件,分析了输入输出设备的数量和性质,根据系统的I/O点数和估算的内存字数的要求,选择了西门子S7-224XP CPU,其程序存储器和数据存储器较大,内置集成了2AI/1AO,2个RS485通信端口,设计了数据采集及PID闭环流量控制等功能,可以实现油气水三相流实验室装置的自动控制,用户在由VB编写的上位机上输入理想的流量值,经过PLC程序运算经模拟量模块输出来控制电动调节阀的开度至达到理想流量。According to the research needs,an experimental apparatus for small high-precision gas-water threephase flow is designed.This paper focuses on the control system design and implementation of the apparatus.By comparing the programmable controller （programmable logic controller,PLC） and the characteristics of the SCM control system,the PLC-based control system hardware component is selected.By analyzing the quantity and the characteristics of the input and output devices,and according to the system I/O points and the estimated requirement of memory words,the Siemens S7-224XP CPU is selected,which has large program memory and data memory,built-in integrated 2AI/1AO,two RS485 communication ports.The data acquisition and PID closed-loop flow control and other functions are designed,which can achieve the automatic control of the gas-water three-phase flow laboratory apparatus,communications by the VB PC user on the host computer enter the desired flow value.After the operation program on the PLC via analog output modules the electric control valve opening degree is controlled to achieve the desired flow rate.

关 键 词：三相流装置 测控系统 PLC PID 

分 类 号：TM93[电气工程—电力电子与电力传动] TN911[电子电信—通信与信息系统]