模糊+PID控制在换热器进水流量控制研究

Research on Fuzzy+PID Control in Water Flow of Heat Exchanger

为了实现对换热器进水流量控制,通过对换热器系统的动态结构进行分析研究,得到了换热器系统的动态数学模型。进口水流量的数学模型是与水位高度的平方成正比的一个关系式,利用动态结构图来对其进行构造;在进口水流量控制中,设计一个模糊控制器和PID控制器,通过设定阈值,实现自动切换机制,可将模糊控制+PID控制自动进行最优工作。经过试验表明,该控制系统算法精度高,响应时间快,稳定性好。

In order to control the flow of water into the heat exchanger,the dynamic structure of the heat exchanger system is analyzed,and the dynamic mathematical model of the heat exchanger system is obtained.The mathematical model of the inlet water flow is a relation which is directly proportional to the square of the water level height,and it is constructed by using the dynamic structure chart.In the inlet water flow control,a fuzzy controller and a PID controller are set up.By setting the threshold value,the automatic switching mechanism is realized,and the fuzzy control+PID control can automatically carry out the optimal work.The experimental results show that the control system has high accuracy,fast response time and good stability.