配電用柱上変圧器モデルと誘導雷現象

抄録

Induction by a vertical lightning channel on an overhead wire over lossy ground is calculated in accordance with Agrawal's model, and the effect of pole-type distribution transformers on the induced voltage waveform is studied.
A transformer decreases the induced voltage and at the same time it increases the rise time of the voltage waveform. As far as the induced voltage waveforms on a medium voltage line are concerned, a transformer can be represented by its capacitive component only in most of the cases. Resonance of a transformer, usually its frequencies being higher than 1MHz, influences the induced voltage waveforms in cases that transformers or surge arresters are connected with an interval of less than 100m and that the rise time of a return stroke current waveform is much shorter than 1μs.