Lightning Withstand of Medium Voltage Switches and Cut-Out Fuses Considering Standard and Nonstandard Impulse Shapes

Lightning discharge activity causes overvoltages in the electric power system, which may result in damage to the equipment and apparatus of the system. The lightning incidence is divided into two types: direct strikes and side strikes [1-4]. Direct strikes are lightning discharges that directly hit the line, structure or equipment, resulting in overvoltages of higher amplitudes. However, they are less common than side strikes, which are discharges that occur near the electric system and induce overvoltages of lower amplitudes than direct strikes, but may also cause damage in the distribution network. In this way, many works have evaluated the effect of side strikes on the insulation of electric power system equipment [5-8]. © 2006 IEEE.