Grey relational analysis using Gaussian process regression method for dissolved gas concentration prediction

The prediction of the dissolved gases content in an oil-immersed power transformer is very important for early fault detection. However, it is quite difficult to obtain accurate predictions due to the non-linearity of gas data. Different machine learning technics have been used to solve this problem, but they neither consider the relationship of different gases nor the sampling errors. In this paper, we propose to use Grey relational analysis (GRA) to calculate grey relational coefficients for gas feature selection and a Gaussian process regression (GPR) to predict dissolved gas value. In this method, both the relationship of gas features and sampling errors are considered. Four algorithms of ANN, SVM, LSSVM and GPR are used in gas prediction. We conducted experiments on eight dissolved gas datasets. The comparison results have shown that the GRA method is effective in selecting good gas features. The performance of prediction of gas values is significantly improved.