【摘要】 以S7-200 PLC为控制器,精馏塔为被控对象,开发了基于PLC的精馏过程控制实验平台。介绍了该实验平台的组成、各组成部分的作用及结构参数等。设计了基于PLC的控制方案和安全联锁系统,实现了对精馏塔的塔釜液位、塔釜加热功率、进料温度、回流比等典型参数的实时检测和自动控制以及发生异常情况时系统会自动启动安全保护措施;描述了监控软件对精馏过程的实时监控等功能。应用结果表明,基于PLC的精馏过程控制实验平台操作简单,人机界面友好,可实现多个教学项目。更多还原

【Abstract】 With the S7-200 PLC as the controller and the distillation tower as the controlled object, the PLC-based distillation process control experiment platform was developed. The composition of the experiment platform, the role of various components, and the structural parameters were introduced. A PLC-based control scheme and safety interlock system was designed to achieve real-time detection and automatic control of typical parameters such as the tower bottom level, tower bottom heating power, feed temperature, and reflux ratio. Besides, the system automatically starts security measures when abnormal situations occur. The monitoring software’s real-time monitoring of the distillation process was also described. The application results show that the PLC-based distillation process control experiment platform is simple in operation, friendly in man-machine interface, and can achieve multiple teaching goals.更多还原