基于虚拟仪器的过程控制系统的设计

Design of Process Control System Based on Virtual Instrument

设计一个硬件在环控制平台,被控象为双容水箱液位系统。采用以计算为核心的虚拟义器替代传统的仪器仪表进行控制,直接与硬件互连,进行硬件在环仿真实验。由于软硬件不能直接互联,通过调用动态链接库函数的方式,解决一般采集卡与LabView软件的接口问题,建立控制界面进行人机交换。采用PID控制策略进行液位控制,对数据进行读取,存储并且实时图形显示。该软件程序模块化,维护方便,提高了开发效率,充分体现出虚拟仪器在控制领域中的独特优势。

This paper designed a control system to control a water level system of two tanks. It took LabVIEW which was a kind of virtual instrument produced by NI as a tool to control the object mentioned above, established hardware in loop platform. Because the data acquisition system was not compatible with LabVIEW, the drive platform was established in order to exchange data with each other correctly. Then it used the data acquired by data acquisition system to create the relation between software and hardware. The PID controller was designed to control the water lever system. It stores and receives data on real time, and at the same time they are showing on graphic. The program can be divided into several parts, they can be maintained easily. And they can load into other ECU or PC directly. From all above,it displays the special advantages of LabVIEW in control field.