Magnetising inrush current in transformers: an overview

In India, the failure rate of distribution transformers has been reported very high especially in the rural and remote areas. In these areas, frequent inrush current is produced in distribution transformers during their energisation. The generation of inrush current during each energisation may be dangerous for health of the distribution transformers. This has motivated the authors for extensive study on inrush current such as causes, modelling, effects and reduction techniques. A case study has also been given on role of creep in the windings due to inrush current as one of the reasons for failure of distribution transformers.

Keywords: creep, energisation, inrush current, power system restoration, failure rate, distribution transformers, winders, rural areas, India, electricity distribution