Analysis of Lightning Impulse Effects on Three Winding Transformer Used in Solar System Based Ansys Maxwell

Abstract

Transformers are in more critical applications in the renewable energy world and having a transformer fail in such a cyclical power station can be disastrous. Over voltage or voltage strike is the most important phenomena for the transformers. Thus, the evaluating and estimating the effects and stresses of these sudden high voltages is important during the transformers life time operation and design stage. Accordingly in this paper the electromagnetic field analyses of the lightning impulse on Photovoltaic (PV) transformer are investigated using ANSYS Maxwell software. The 3D and 2D model simulation of the PV transformer is carried out to determine the electric field and voltage distribution on critical regions which can cause breakdown on insulation material and damage transformer windings and affects transformer working. Afterwards according to the simulation result, the subjected transformer was designed considering the relative critical regions and performs the full wave lightning impulse test in factory area to verify the dielectric strength of the transformer. This study provides better understanding of the lightning impulse voltage effects with localization of the critical regions on the PV transformer and helps to improve the withstand capability of the transformer against the lightning impulse voltages during the design and production stage.