基于雷电行波时域特征的输电线路雷击类型辨识方法

Identification of Back Striking and Shielding Failure on Transmission Line Based on Time Domain Characteristics of Traveling Wave

雷击类型的识别可为线路运维人员提供方向性指导。根据输电线路雷击过电压原理和输电线路边界条件构建输电线路在雷击和线路故障条件下,三相故障行波极性满足的对应关系,提出根据三相电流行波的极性异同来识别线路反击。进一步通过比较雷电和线路故障时,其暂态行波能量变化的特点,提出基于修正能量比的输电线路故障和绕击的判断方法,最终完成线路雷击类型的识别。通过仿真和现场实验验证了此方法的正确性,具有较好的应用价值。

Identification of lightning type can provide directive guidance for the operation and maintenance of transmission lines. In this study, the correspondence is constructed satisfied by the three-phase polarities of fault traveling wave currents when a fault of transmission line is caused by lightning. On the basis of the lightning overvoltage theory and the boundary conditions of transmission line, the back striking is identified according to the differences and similarities in three-phase polarities of current traveling waves. A judgment method is proposed for the transmission line fault caused by lightning and shielding failure based on modified energy ratio, considering the energy variation features of transient traveling wave. Finally, the identification on lightning types of the transmission line is achieved. Simulation and field experiment verify the proposed method.