Statistic Distribution Law of the Chromatographic Data of 110 kV Running Current Transformer

This paper mainly analyzes the oil chromatographic test data of 110 kV oil-immersed current transformer in Guangzhou Power Grid from 2005 to 2023, and finds that it mainly obeys approximate Lognormal distribution or approximate Weibull distribution. The 95% quantile values of H2, CH4, C2H6, C2H4, CO, CO2 and total hydrocarbon are 164 u L/L, 22 u L/L, 7.2 u L/L, 2.2 u L/L, 639 u L/L, 2400 u L/L and 27.2 uL/L respectively. Through the analysis of the influence of manufacturers and equipment models on the 95% quantile value of different gas content, it is concluded that for alkane gas, the 95% quantile value of LCWB6 oil transformer is higher than that of LB7, and CO and CO2 have no obvious law. By analyzing the 95% quantile value, it can provide reference for the selection of early warning value and differential operation and maintenance of equipment.