Transformer modeling suitable for DC/AC and AC/DC conversion chains

Abstract

The aim of this work is to compute a transformer model capable of reproducing some real aspects and phenomena specifically in DC/AC and AC/DC power conversion applications. This issue is incited by the increasing presence of power converters in modern networks leading to more harmonics and loss. Actually, the connection of photovoltaic or wind systems to the grid is notably growing up in addition of HVDC links. All of the cited systems need power converters to insure proper working. The suggested transformer model is developed using MATLAB/Simulink/SimPowerSystems software based on 10 kVA 230/230 V transformer data. Magnetic core geometry is supported as well as core saturation, dynamic iron resistance, winding impedance frequency dependency and capacitive effects. Parameter validation was made through several tests such as transformer unbalanced supply and load and transformer insertion in some power conversion chains. Results have shown that the model is suitable for calculating windings and iron loss under non sinusoidal excitations.