分子筛氧浓缩器实验台集散控制系统的设计

Distributed Control System Design in Molecular Sieve Function Experiment Station

进行分子筛性能实验时,需要精确控制入口冲压空气的温度、压力以满足国军标要求,同时为了解决小流量冲压空气的温度难于控制的问题,设计了基于串行总线结构的集散式控制系统;采用RS-485协议实现管理台和下位智能仪表的通讯和控制,通过仪表控制和数字PID控制相结合的办法实现了小流量冲压空气温度的精确控制;实验效果表明,该实验台的温度、压力控制效果良好,具有精度高、调节速度快的优点;这种控制办法是合理有效的,对于类似的控制问题具有参考价值。

Molecular sieve function experiment requires accurate control of the temperature and pressure of the ram air at entrance, so as to meet the GJB requirements. Since it is difficult to control the temperature of low mass flow ram-air, distributed control system based on serial input output bus is designed, and communications and control of management station and intelligent meters in field station are realized by adopting RS- 485 protocol. In this way, the temperature of low mass flow ram air is controlled in an accurate manner through combining meters control and digital PID control. The results of the experiment prove that the experiment table can control the temperature and pres sure accurately and quickly. This control method is reasonable and effective, and can be of reference to similar control issues.