Determining the traveling wave coefficients in power transformers using detailed model

Abstract

One of the powerful methods by transformer transient analysis is traveling wave theory. Two important factors named reflection and transmission coefficients are defined in this method, so that the applying of theory is been easier. These coefficients are given usually in frequency domain with help of executing some tests on transformer. Since such tests are difficult, costly and even sometimes impossible, using a model to calculate the above mentioned coefficients is very helpful. This paper shows the validity of detailed model based on self and mutual inductances by calculating of these coefficients. A three phase 2.5 MVA and 6300/420 V transformer is used by this investigation.