油溶解气体色谱分析中的小型真空在线脱气技术

A Small Vacuum On-line Extraction Technology for the Automatic Chromatographic Analysis of Gas Dissolved in Insulating Oil

基于当前气相色谱分析技术的发展,针对变压器绝缘油中溶解气体色谱在线分析的状况,提出了色谱系统对气相中气体组分体积分数最小检测值极限算法的数学模型。应用该模型,可对脱气室和集气室体积进行小型化计算和试验典型配置。在此基础上,文中设计了一种新型的小型真空在线脱气系统(10cm×10cm×20cm)和新型的全自动进样器(5cm×5cm×2cm)。系统采用全自动化控制。用标准气体试验确定了定量器体积(0.769mL),用样品气体试验对整个系统进行了检测。试验结果表明,文中所设计的小型真空脱气系统能较好地用于变压器绝缘油中溶解气体在线色谱分析。

Based on the current development of the gas chromatographic analysis technology and the status quo of the automatic chromatographic analysis of gas dissolved in transformer＇s insulating oil, a mathematical model for the lowest concentration of gas components in the gas phase is proposed, which can be detected by gas chromatography. By using the mathematical model and conforming with the lowest detectable concentration specification of gas components in oil and the sensitivity limit to the chromatographic analysis system, the minimum volume of the oil chamber and gas chamber can be calculated and designed. Based on this, a novel small vacuum on-line extraction system （10 cm× 10 cm× 20 cm） and a novel automatic instrument （5 cm×5 cm×2 cm） for the sample gases transmission is designed. The volume （0. 769 mL） of the quantity fixing vessel is determined by experiment on standard gases and the whole system is examined by experiment on the sample gases. The result shows that the small vacuum extraction system can be satisfactorily used for the on-line application of the chromatographic analysis of gas dissolved in transformer insulating oil.