Prediction of current in a substation in order to schedule thermography

Abstract

It is important to predict the current in a line in the electrical grid for example when planning thermography or handling dynamic rating. This paper takes data from a Swedish substation from 10 years and applies analysis of variance (ANOVA) to construct a linear model. The factors are the time of the day, the day of the week and the week number. About two thirds of the variance in the data can be explained by the model, but the means are too low to attain a current of at least one third of the current for which the equipment is rated. Thus the model is not good enough to plan thermography for the studied bay in the substation. However the model is able to predict the current and can also be used to predict power flows in the electric network.