A New Method to Evaluate Residual Flux Thanks to Leakage Flux, Application to a Transformer

Abstract

This paper presents a new method to estimate the residual flux in the magnetic circuit of a transformer, which is the key data to determine the ideal closing time for the re-energization of a transformer. The methodology described is based on the measurement with fluxgate sensors of the magnetic field induced by the leakage flux around a single-phase transformer.