Influence of corona on the voltages induced by nearby lightning on overhead distribution lines

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Without loss of generality, the return stroke can be treated as a current pulse propagating along the leader channel while undergoing attenuation and dispersion. According to the measurements, the return stroke travels along the leader channel with a speed less than the speed of light. However, if the return stroke speed were to be lower than the speed of light, the propagating return stroke would generate an electric field traveling ahead of the return stroke front with the speed of light. Since the leader

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The voltages induced by nearby lightning strikes are a major cause of outages in power distribution systems. We compute such voltages taking into account the effects of the dart leaders that precede subsequent return strokes in both natural and rocket-triggered discharges. The results show that for stroke locations that are approximately alone, the line prolongation, the leader electric field change has a significant influence on the amplitude and shape of the induced voltages. The taking into account of th

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A model for the calculation of lightning-induced voltages is presented allowing the assessment of the effect of corona when power distribution lines are illuminated by lightning electromagnetic fields. It is shown that, as far as corona can be described by means of an increase of capacitance after the voltage has reached a threshold value, corona can produce an increase in the peak amplitude of the induced voltage. An explanation of this result is given. The need for experimental results to test this theore

The paper presents a modelling procedure for evaluating the voltages and currents induced on transmission lines by nearby lightning. Models are needed in order to evaluate lightning effects where experimental results are not available. These models allow better design and coordination of the protection of power and telecommunication networks against lightning induced effects

Influence of corona on the voltages induced by nearby lightning on overhead distribution lines

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Influence of corona on lightning-induced voltages on overhead power lines

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