Investigations of no-load and load losses in amorphous core dry-type transformers

Abstract

Amorphous metal core dry-type distribution transformers have a significant place in today power market since they exhibit 60-70% lower no-load losses when compared to the standard steel based transformers. At typical loading regimes these losses are the most significant ones for a distribution transformer. In order to improve the design and to shorten significantly the time to market of such products numerical analysis of the no-load as well as of the load tests are of paramount importance. The present manuscript describes the FEM based numerical analysis performed on a 1 MVA unit, in an industrial environment, with the emphasis on the importance of non-linear and anisotropic magnetic modeling as opposed to isotropic for the accurate computation of no-load losses. The choices for the analysis regime and the specific analysis tools are described in details - and results are given to prove the salient points of this particular design of a transformer.