Transient Transformer Inrush Currents due to Closing Time- and Residual Flux Measurement- Deviations if Controlled Switching is used
نویسنده
چکیده
During energisation of power transformers, transient inrush currents with peaks up to the short-circuit current may arise. Using controlled switching taking into account the residual flux, the transients can – in theory – be eliminated completely. Real factors such as closing time scatter and residual flux measurement uncertainty have to be considered when checking the suitability of controlled switching in the field. On account of this, a systematic transformer inrush current study depending on closing timeand residual flux measurement deviations for a 400 kVA dry-type distribution transformer will be presented in this paper. To carry out the systematic study for the energisation of the first phase, an interface between MATLAB and EMTP-ATP was implemented to share the strengths of both tools. Finally, recommendations for acceptable closing timeand residual flux measurement-deviations depending on the tolerable inrush current peak are given.
منابع مشابه
Determination of Acceptable Closing Time Scatter and Residual Flux Measurement Uncertainty for Controlled Switching of Transformers
Theoretically, controlled switching taking into account the residual flux is able to fully eliminate inrush currents. Due to non-idealities in the field (closing time scatter, residual flux measurement uncertainty) that significantly affect the performance of controlled switching, inrush currents of 1.0 pu must be tolerated. To calculate the maximum acceptable tolerances of both nonidealities i...
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