When fast gas chromatography (GC) in temperature programming,due to the characteristics of chromatographic columns with low heat capacity,linearity and overshoot of warming up are difficult to control,affect repeat ability of instrument,resulting in overlapping peaks.In order to solve this problem,a kind of temperature control system based on intelligent PID algorithm is developed.The system selects LTM column,with the platinum temperature measuring wire as temperature sensor component,the temperature acquisition and control circuit is designed.On the basis of incremental PID,target temperature segment is divided into several sub regions,and the temperature compensation is introduced.The compensation value is linear with the heating rate.The experimental results show that the error of the temperature rising rate after compensation is 2.58 ％,the linearity is 99.92 ％,and the overshoot is less than 3 ℃,which meets the requirement of the system.%针对快速气相色谱仪(GC)在程序升温时,由于色谱柱低热容,导致升温的线性度和超调难以控制,影响仪器的可重复性,产生峰重叠的问题,开发了一种基于智能比例-积分-微分(PID)算法的色谱柱温控系统.系统选用LTM柱,以该柱自带的铂测温丝作为温度传感器元件,设计了温度采集和控制电路.算法上,在增量式PID的基础上,将目标温度段划分为多个子区间段,引入温度补偿控制,补偿值的大小与升温速率呈线性关系.实验结果表明:补偿后,算法升温速率误差为2.58％,线性度达到99.92％,超调在3℃以内,满足系统需求.
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