Predicting the Effect of Voltage Harmonic Phase Angle on Transformer Core Losses

Although the integration of power electronics in today’s power grids has brought numerous benefits, it has also favored the emergence of harmonics components which degrade power quality and give rise to extra losses. This article analyzes the effect of the harmonics of the applied voltage and their respective phase angles on the core losses of power transformers. For the determination of transformer core losses under nonsinusoidal voltage supply, a method based on the absolute mean value of the applied voltage is proposed and its accuracy is compared with conventional methods found in the technical literature. Experimental results obtained at different levels of total harmonic distortion confirm the improved accuracy of the method proposed in this article, which requires only the knowledge of the applied voltage to determine the core losses, combining simplicity and accuracy.