As the basic part of power system, 10kV distribution network has a great influence on the power transmission status, and its operation stability has an impact on the practical ability and power supply reliability of later users.
2.1 single-phase ground fault
Single-phase ground fault conditions for many reasons, including: thunderstorms, air humidity is too large and other conditions, by the line breakdown, joint fusing, corrosion and other issues caused by oxidation damage, including single-phase disconnection caused damage.
2.2 short circuit fault
(1) Under the external force, such as the damage caused by the mechanical force, the vehicle impact, the cul-de-sac hanging wire, the foreign body caused by the collapse of the pole and other conditions are common problems.
(2) The number of lightning strikes and overhead insulated wires is more and more increasing the frequency of lightning accidents. In urban buildings, there are many lightning protection facilities and facilities, and the corresponding distribution lines are generally not affected by lightning strikes. However, the area covered by the line is wide, including the fields such as the fields and hillsides. As a result, the damage in the entire surrounding area is influenced by the location, and the area easily becomes the lightning current channel. Lightning strike voltage is very high, the current moment is very large, distribution lines and the phase distance between the insulation performance simply can not afford, so the line phase arc short circuit or insulation breakdown, resulting in short circuit between the ground.
2.3 bird damage problem
Line corner pole, isolating switch and other locations are generally easy to become bird stay area, corresponding to its higher contact density, prone to accidents. The distance between the general to meet the requirements of 30cm, but lack of safety margin, will lead to the whereabouts of birds, flying process, prone to short-circuit problem.