Neutral Point Overvoltages in Wye-Wye Connected Distribution Transformer Caused by Lightning Current in Low-Voltage Winding
نویسندگان
چکیده
Lightning strokes are a main source of transformer failures in distribution systems. The discharge lightning current through transformer's high-voltage (HV) side arresters leads to ground potential rise the tank. In case wye-wye connected with ungrounded HV neutral point, can drive low-voltage (LV) windings that an excessive voltage point by inductive transformation. Simulations measurement-based model demonstrate several times impulse test arise close strike overhead line. use LV surge combination proper grounding on HV-side effective ways reducing overvoltage.
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ژورنال
عنوان ژورنال: IEEE Transactions on Power Delivery
سال: 2021
ISSN: ['1937-4208', '0885-8977']
DOI: https://doi.org/10.1109/tpwrd.2020.3027960