For an Improved Evaluation of Conventional Losses of Transformers for Converters

Evaluation of conventional losses in rectifier transformers, as performed according to the various national standards, and particularly as performed according to International Electrotechnical Commission (IEC) recommendations, is scarcely satisfactory because it does not take into proper consideration the pulsating nature of the current and neglects some elements that give a fair contribution to total losses. Some test elaboration methods are proposed, as well as a test circuit to evaluate in a more accurate way the losses in transformers, interphase transformers, and saturable reactors. Some examples are given, and the available experimental result is in a good agreement with the calculations.