Analysis of the Influence of Electric Field on Current Error of High-Voltage Three-Phase Three-Element Combined Transformer

Abstract:

High voltage three-phase three-element combined transformer, widely used in power systems of 10kV, 35kV and the like, is important in guaranteeing the safe and stable operation of power system, and ensuring the fair and equitable metering of electric power. At present, when verified by single-phase verification method, combined transformer exposed to the situation which doesn’t match its actual operation situation, as a result, verification results can’t reflect the true error characteristics of combined transformer. So, it is suggested to adopt three-phase verification method to verify combined transformer. However, when combined transformer is verified by three-phase verification method, it has not been clear yet that what influence electric field generated by voltage has on current error. In this paper, through current error test on combined transformer with three-phase verification method at different voltage, it is discovered that electric field has a larger influence on current error at lower current (especially at 1% rated current),with the increase of current, the influence of electric field on current error decrease gradually till negligible. The use of three-phase verification method and appropriate modification of current error limits are recommended when combined transformer is verified.

• Periodical: Applied Mechanics and Materials (Volumes 672-674)
• Pages: 755-761
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.672-674.755
• Online since: October 2014
• Authors: Gang Liu*, Bo Jiang, Lin Dong Ren, Fu Zhou Zhang, Bing Ai, Wei Jiang
• Keywords: Combined Transformer, Current Error, Electric Field, Three-Phase Three-Element

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