Transient overvoltages on distribution underground cable inserted in overhead line

In recent years, an increased number of windstorms has led to a surge in damage of 22 kV and 35 kV lines caused by fallen trees. Those incidents result frequently in long power outages and increased maintenance costs of distribution networks. This paper is inspired by a recent trend consisting in the replacement of concerned sections of overhead lines by cables. Such an approach is called “cable sections inserted in overhead lines” or, simply, “cables inserted in lines”. This solution brings numerous changes concerning the operation of distribution networks and it can be a potential source of faults due to the increased danger of the penetration of lightning overvoltage to the cable and of the subsequent breakdown of its insulation..