Reducing Losses in Distribution Transformers

Virginia Polytechnic Institute and State University; CINVESTAV; Katholieke Universiteit Leuven; Universidad Autonoma Metropolitana-Azcapotzalco;
IEEE Power Engineering Review 10/2002; 22(9):61-61. DOI: 10.1109/MPER.2002.4312601
Source: IEEE Xplore

ABSTRACT This paper examines three methods of reducing distribution transformer losses. The first method analyzes the effects of using aluminum electromagnetic shields in a distribution transformer. The goal of placing electromagnetic shields in the distribution-transformer tank walls is to reduce the stray losses. A 500 kVA shell-type transformer was used in the experiments. The overall results presented indicate that stray losses can be considerably reduced when electromagnetic shielding is applied in the transformer tank. In the experiment, the tank walls were lined with aluminum foil. The possibility of reducing the dielectric losses was shown through experiments in the second method. The third method analyzes the behavior of wound-cores losses in distribution transformers as a function of joint configuration design parameters. The joint configuration used in this paper is called step-lap joint.

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