Perda Adicional no Núcleo em Transformadores Trifásicos Alimentando Cargas Não-Lineares (Additional Loss in the Core of Three Phase Transformers Feeding Non Linear Loads)

Luiz Roberto Lisita (lisita@eee.ufg.br), José Wilson Lima Nerys (jwilson@eee.ufg.br), Adalberto José Batista (batista@eee.ufg.br), Antonio Melo de Oliveira (melo@eee.ufg.br), Alexandre Cândido Moreira (amoreira@dsce.fee.unicamp.br)


Escola de Engenharia Elétrica e de Computação, Universidade Federal de Goiás, Brazil
This paper appears in: Revista IEEE América Latina

Publication Date: March 2004
Volume: 2,   Issue: 1 
ISSN: 1548-0992


Abstract:
As a consequence of the increasing technological development of electrical and electronic equipments, which are supplied by distribution transformers, the current and the voltage of transformers have presented distorted waveforms. These non-sinusoidal currents and voltages in transformers result in additional losses, which cause increase in temperature and reduction to the transformer insulation and lifetime. One of these losses is located in the transformer core, which may cause increase in the excitation current and in the audible noise. The purpose of this work is to analyse the behaviour of the voltages and currents of distribution transformers when they are supplying energy to non-linear loads and, from this analysis, to calculate the Core Loss (PNL). The measurements are performed using the back-to-back configuration and the adopted model is the three-phase instantaneous model with measurements and calculus made per phase. This work is implemented using a Data Acquisition System (DAQ) and the LabVIEW programming language.

Index Terms:
digital measurement, harmonics, non-linear loads, transformer losses, core losses, derating   


Documents that cite this document
This function is not implemented yet.


[PDF Full-Text (506)]