Study of energy efficiency in dry-type transformer under sub- and interharmonic in the power supply voltage

Additional losses in transformers due to harmonic distortion cause further heating in their structural parts, and damage their suitable operation, thereby reducing their lifetime. This paper proposes an energy efficiency study in transformer, by comparing the temperature measurements obtained from a 10 kVA three-phase dry transformer under sinusoidal voltage and current conditions, and under power supply voltage with sub- and interharmonic. It is also performed a comparison between experimental and simulation results obtained from a model 3D transformer developed in COMSOL Multiphysics software.