Observation of Natural Lightning-Induced Voltage on Overhead Power Lines

This paper presents the analysis and observation results of the induced voltage waveforms caused by nearby natural lightning on overhead power lines in the Guangzhou field experiment site during the summer of 2008. Peak values of the induced voltage for 36 natural lightning return strokes ranged from 0.21 to 3.87 kV. And the double-peak oscillation phenomenon can be found in the waveforms. The interval time of adjacent return strokes ranged from 17.1 to 430.1 ms. The average 10%-10% peak value duration time of induced voltage waveform of the first return strokes is 244.6 mu s, and that of the subsequent return strokes is 83.2 mu s. The induced voltage waveforms on the live and neutral conductors are almost the same, while the induced voltage amplitude on the live conductor is slightly larger than that on the neutral conductor. The lightning location system data indicate that the induced voltage on the live and neutral conductor may be of either positive or negative polarity, depending on the lightning ground strike points. However, the amplitude of the induced voltage calculated by the Rusck model is smaller than those of the observation results, with the former being 60% of the latter.