Analysis of switching on selected electrical high voltage circuits
Journal Title: Mining – Informatics, Automation and Electrical Engineering - Year 2016, Vol 525, Issue 1
Abstract
Physical phenomena occurring in high-current contact systems of electric switches, when switching on unloaded transformers and capacitor banks, are much more dangerous than the phenomena occurring in the contact switch systems installed in other electric power systems. Switching on unloaded transformers may be accompanied by significant over-currents, greatly exceeding the nominal currents of the transformer. Connecting the capacities of capacitor banks causes transients in the circuit, leading to significant, fast over-currents and over-voltages. High-frequency currents may be transmitted by electromagnetic couplings to control circuits and other low-voltage circuits. The subject of the paper is the analysis of transient processes during switching on unloaded transformers and the capacities of capacitor banks. Additionally, the authors assess the impact of the power switching phase in particular circuits on the over-currents which arise there.
Authors and Affiliations
Stanisław Jan Kulas, Hendryk Supronowicz
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