雷击跳闸率毕业论文

In recent years, guangdong individual areas of 10 kv distribution line ray against accidents occur frequently, serious harm to the distribution network power supply reliability and safety of power grid, the impact of the people in the life and production of electricity, and even brings personal casualties, the accident area considerable economic losses. Therefore, we should be to the dangers of lightning is clear enough cognition, so this paper describes 10 kv overhead distribution line lightning discharge, this paper introduces the principle of lightning the formation and development of the process, ray voltage and the formation process of lightning current, and gives the lightning parameters and lightning resistant level, lightning trip-out rate, induction thunder and the main calculation method of the direct lightning. And according to 10 kv overhead line often occur fault characteristics, and combined with 10 kv power distribution line operation characteristics, study 10 kv power distribution line lightning protection measures, to ensure the safe operation of the 10 kv power distribution line has important practical significance. 应该差不多。

雷击跳闸是过压保护

雷击跳闸率n 的概念：每百公里线路、40雷电日，由于雷击引起的开断数（重合成功也算一次），称为该线路的雷击跳闸率，简称跳闸率，跳闸率是衡量线路防雷性能好坏的综合指标，它可定性地用下式表示：n=N×P1×η式中，N——线路上的总落雷数P1——是雷电流幅值等于或大于耐雷水平的概率η——建弧率NP1——表示会引起闪络的雷击数。所以NP1η表示会引出开关跳闸的雷击次数，即跳闸率 。

电力输电线路雷击跳闸是因为雷电击中输电线路后，基于输电线路或杆塔的等效阻抗产生的过电压而保护电力设备的断路动作。根据相关研究输电线路的等效阻抗远远大于杆塔的等效阻抗，因此雷电绕击对于输电线路的过电压危害也远远大于直击雷的危害。