DRAWING THE MAXIMUM LIGHTNING OVERVOLTAGE PROFILE IN TRANSMISSION LINE

Lightning is one of the factors producing overvoltages in power systems. In order to be prevented from its damaging effects, it should be considered as a serious factor for insulation coordination in power systems especially transmission lines. Therefore, the assessment of lightning overvoltages in transmission lines is a serious necessity. For this purpose, we used the transmission line theory. The distribution of the currents and voltages resulting from lightning on overhead lines in unload and matched line position and on overhead-cable line , also the distribution of currents and voltages resulting from several pulses of lightning have been assessed. In this paper, in addition to distribution of currents and voltages using the above mentioned theory, drawing the maximum overvoltage profile as function of the distance from exposed end, also overvoltage at a specific point of line have been take into consideration. Finally, voltage at the exposed end of line and maximum overvoltage profile have been drawn.

کلیدواژه ها:

Transmission Line Theory ، Distribution ofCurrents and Voltages ، Maximum Overvoltage Profile