© 2021, International Organization on 'Technical and Physical Problems of Engineering'. All rights reserved.Transformers are the main components of electrical systems and are widely used in renewable energy systems that transfer the energy they produce to the grid. Recently, due to the lack of fossil fuels, governments have encouraged utilities to seek alternative energy sources. In this respect, PV (Photovoltaic) power plants have become more important in recent years. Accordingly, transformers are one of the most critical equipment of PV plants, and their safe operation and stability in the electrical network are important. This type of transformer is energized from the inverter and needs to be customized to work with each system. The main purpose of this study is to analyze and model the magnetic field behavior of a special type PV transformer. This transformer has two similar separate windings on the low voltage side and one winding on the high voltage side. The simulation results are compared with those obtained from the experiments. The effects of the unbalanced operation of the inverters on the transformer performance were also investigated in this study.