Power loss due to high harmonics in power transformer when use for dc drive of hoisting machines

The paper presents the investigated results of performance of power transformers when used for converters supply of DC drive of hosting machines. Particular attention was paid on the power loss due to deformed current and voltage waveforms. The active and reactive power losses were compared for the newly employed transformer to this working more that 16 years. On the basis of the measurements the conclusions and recommendations for use in practice are formulated.