高效液相色谱法测定绝缘油中糠醛含量的不确定度评定

Uncertainty Evaluation for the Furfural Content in Transformer Oil by HPLC

绝缘油中的糠醛含量能够评估变压器绝缘纸的老化状况,并反映其绝缘性能。通过高效液相色谱法对绝缘油中糠醛含量进行定量分析,建立数学模型,确定测定结果的不确定度来源为糠醛标准物质、标准油液的配制、标准曲线的拟合、样品制备、回收率、测量重复性,并对测试结果进行不确定度评定。实验结果表明,绝缘油中糠醛样品浓度为1.05 mg/kg,其扩展不确定度U_(95)=0.03 mg/kg,其中标准曲线的拟合是高效液相色谱法测定糠醛结果不确定度的主要来源。

Furfural content in transformer oil can evaluate the aging condition of transformer insulating paper and reflect its insulation performance.Through the quantitative analysis of furfural content in transformer oil by high performance liquid chromatography,the mathematical model was established.It was determined that the uncertainty sources of the determination results are furfural reference material,preparation of standard oil,fitting of standard curve,sample preparation,recovery and measurement repeatability,and the uncertainty of the test results was evaluated.The experimental results showed that the concentration of furfural in the electric insulating oil is 1.05 mg/kg,and its extended uncertainty U_(95)=0.03 mg/kg,the fitting of standard curve is the main source of uncertainty in the determination of furfural by HPLC.