Distribution transformers performance

This paper present the results of a survey of load, no-load losses and dielectric strength of 123 new and repaired distribution transformers tested by the High Voltage Laboratory of the Federal University of Itajuba within a Research and Development Project in partnership with the AES-SUL - Distribuidora Gaucha de Energia S.A.. Based on these results were defined transformer efficiency curves. These curves were compared with the European Standard PROPHET, in order of supplying data to evaluate the possibilities of reduction of losses of the distribution transformers manufactured in Brazil. The results show the necessity of a new evaluation of the Brazilian National Transformer Standards and support the claim for a rigorous quality control of the manufacturing process of distribution transformers.