Obtaining the magnetization characteristic of a transformer using inrush current waveforms

Abstract

The magnetization characteristics of installed transformers are quite often unknown, or different from those documented due to ageing. Further, a precise method of modelling the nonlinear flux-curve of a transformer is a requirement for electromagnetic transient studies. A reliable method is thus needed to determine the magnetization characteristics of installed three-phase transformers. Transformer parameters are usually determined in the manufactory, mainly using the open circuit and short circuit tests. However, it is not possible to conduct these tests in the field.