以中等纯度的精馏塔为研究对象，考虑到不等分子溢流的影响和非理想的汽液平衡，可以得到塔顶产品轻组分含量Y与回流量L之间的传递函数为：



控制要求：

1.采用积分分离 PID控制算法将塔顶轻组分含量Y控制在0.99

2.采用继电法整定PID参数

3.整定效果验证：当被控过程参数时变时，如滞后时间由4→8，开环增益由3.4→6时, 讨论PID控制的响应速度及鲁棒性问题，考察当系统参数发生改变时，上述PID参数是否选取合适。

-Moderate purity fractionator as the object of study, taking into account the ranging molecular overflowing and non-ideal vapor-liquid equilibrium can be obtained by the transfer function between the content of light components of the overhead product Y and back to the flow L: Control Requirements: 1. integral separation PID control algorithm to control the top of the tower light component content Y 0.99 2. relay Law tuning PID parameters. tuning effect is verified: change When accused of process parameters, such as the lag time from 4 → 8, the open loop gain discussed from 3.4 → 6, the PID control of the response speed and robustness issues investigated when the system parameters are changed, the PID parameters select appropriate.