列管式热交换器的特征模型控制

Tubular heat exchanger based on characteristic-model control

列管式热交换器具有时滞和大惯性的特点,其出口温度会受到冷热流体流量和入口温度等的干扰,一般的PID控制系统的超调量大,过渡时间长,动态特性较差;本文通过研究热交换器的过程特性,建立对象特征模型,利用在线辨识构建自适应控制律,实时更新控制器参数,使用西门子SIMATIC PCS7对热交换器对象进行出料口的温度控制。结果表明,用该方法建立的热交换器控制系统能够很好地克服对象存在的各种扰动,缩短了过渡过程时间,具有良好的动态性能。

The tubular heat exchanger has the characteristics of time delay and strong inertia, and the temperature of its discharge port is often disturbed by the fluid flow and their entrance temperature of cold and hot. Generally, PID control system has a large overshoot and long transient time with a bad dynamic performance for the objects. The characteristic of a heat exchanger is studied and an intelligent adaptive control law based on characteristic model is proposed by updating its parameters using the on-line parameter identification. SIMATIC PCS7 is used to control a temperatu3＂e of the discharge port in a tubular heat exchanger. The results show that the heat exchanger control system can be well adaptive to the change of production conditions, and make shorten the time of the transition process, as well as has a good dynamic performance.