Estimation of Electrical Characteristics in Equivalent Circuit Model of Non-ideal Potential Transformer

Abstract

In this paper equivalent circuit model of a non-ideal potential transformer (PT) with the model parameters determined practically using open-circuit and short-circuit tests. The experimental setup for determining the equivalent circuit parameters is presented.  As an example of the usefulness of the non-ideal equivalent circuit of the PT, the parameters evaluated in the lab are used to calculate two important transformer characteristic; percentage regulation and maximum efficiency. The equivalent circuit of the tested transformer is also simulated using the LTspice/SwCAD III simulator to study some electrical characteristics of the PT.  For instance, the frequency behavior of some parameters in the equivalent circuit is investigated accordingly.  The parameters behaviors at frequencies up to 100 Hz, such as copper loss, iron loss, series impedance and shunt impedance, has been indicated in this paper.

Keywords: Potential transformers, equivalent circuit model, parametric identification, Electrical simulation, transformer characteristics.