Finite Element Modelling of Flux Density Distribution in Three Phase Transformer Under Nonlinear Load Condition

Abstract

For a transformer under linear load operation, the current into the magnetic material core consists of only fundamental component. However under nonlinear load, the current consists of fundamental and harmonic components with certain percentage of harmonic distortion. It changes flux density as the current is no longer sinusoidal. This paper explores the in-similarity of flux density reading of three phase three limb power transformer under linear and nonlinear load conditions. A finite element model is designed and solved using Opera, a Finite Element solver in order to illustrate flux density values under variation of loads. Results of this paper points to the need to make changes towards dimensions of power transformer core in order to avoid potential malfunction.

Keywords

• current harmonic
• flux density
• nonlinear loads
• total harmonic distortion (thd)
• transformer core