Abstract:In order to realize the intelligent evaluation of power transformer insulation status,an evaluation method for oil - paper insulation of transformer is proposed based on kernel principal component analysis and random forest algorithm. Recovery voltage method ( RVM) is to study insulation aging status of power transformer. In order to overcome the limitations of single classifier,random forest ( RF) is introduced to get classifier groups. The randomness of training samples and feature selection can avoid the problem of overfitting. The differences are small among classifiers built with features when there are few features available. The original samples are analyzed by using kernel principle component analysis ( KPCA) so as to increase the number of features. Then random forests are constructed to get classifier groups in high dimensional kernel space. Finally,the voting results show that,the differences among classifier groups are improved effectively by KPCA. And results of the state diagnosis based on KPCA and random forests have a higher accuracy.