Deriving and validating an electrodynamic model of a voltage transformer from scratch

Abstract

Comprehending the in-depth functioning of a voltage transformer beyond the trivial voltage ratio, generally deducted from the application of Faraday’s law to an open secondary circuit, can be quite challenging for both students and teachers. In this paper, the authors propose an approach that uses Faraday’s and Ohm’s laws alone to derive an electric equivalent circuit for a transformer, with which is possible to accurately explain and predict currents and voltages in its primary and secondary coils under different load resistors connected to the secondary. The authors intend to use a common real-world application as motivation for students to learn Faraday’s law in the context of a modelling and simulation framework, which consists of deriving a model from fundamental physical laws that, after experimental validation, is capable of accurately predicting and explaining a complex phenomenon.