Multivariate Statistical Analysis of Thermal Aging Characteristic Parameters of Oil-paper Insulation
Ke Wang · Gao dianya jishu · 2010
The oil-paper samples constituted by #25 mineral oil and ordinary Kraft paper were thermally aged at temperatures of 90°C,110°C and 130°C.The degree of polymerization of insulation paper and some aging characteristics parameters,such as furfural,dissolved gas content in oil,and acid,water content in oil,were regularly sampled and measured during the aging process.Stepwise regression analysis and factor analysis of multivariable statistical analytics were introduced to analyze various aging characteristic parameters of oil-paper insulation.Stepwise regression results on the test data indicate that a closer linear correlation exists between logarithm of furfural and DP which represents the aging condition of oil-paper insulation than the linear relationship between acid content and DP.Moreover,other characteristic parameters have no linear relationship with DP.Meanwhile,factor analysis results demonstrate that thermal aging characteristic parameters of oil-paper insulation can be grouped in two principal component factors which have not only definite physical meaning but also exponential relationship with DP of insulation paper.