输电线路杆塔接地极冲击接地电阻特性分析

为研究雷电流流经输电线路杆塔接地极的冲击特性,运用CDEGS软件仿真分析杆塔接地极在冲击电流作用下的冲击特性。分析水平接地极及四种改进接地极的冲击特性,探讨不同接地极尺寸以及不同土壤电阻率对冲击接地电阻的影响规律。得到接地极长度及半径对水平接地极冲击接地电阻的影响规律,接地极冲击接地电阻随水平接地极长度的增加而降低,但逐渐趋于稳定;同时获得垂直接地极对四种改进接地极的冲击接地电阻特性,为实际工程中采用合适的方法降低杆塔冲击接地电阻提供了参考。

Analysis on Impulse Grounding Resistance Characteristics of Transmission Line Tower Grounding Electrode

In order to study the impulse characteristics of transmission line tower grounding electrodes under lightning currents,the impulse characteristics of grounding electrodes under impulse currents are simulated by CDEGS software.The impulse characteristics of the single horizontal grounding electrode and four improved grounding electrodes are analyzed,the influence law of different grounding electrode size and different soil resistivity on impulse grounding resistance is discussed.The influence law of grounding electrode length and radius on impulse grounding resistance of horizontal grounding electrode is obtained,the impulse grounding resistance decrease with the increase of the grounding electrode length,but tend to be a constant value;and the impulse grounding resistance characteristics of vertical grounding electrodes on four improved grounding electrodes are also obtained,a reference is provided for using proper method to decrease the impulse grounding resistance in practical project application.