土壤频变性对接地装置冲击系数的影响分析

Analysis on the Influence of Soil Frequency-Dependence Characteristics on the Impulse Coefficient of the Grounding Device

冲击系数是反映输电线路杆塔接地装置冲击特性的重要参数,对其进行准确计算是防雷优化设计和提升输电线路耐雷性能的基础。在深入分析土壤介质微观极化过程的基础上,引入Visacro-Alipio土壤频变特性公式,建立了考虑土壤电参数频变性的接地装置冲击特性数值模型;利用所建模型仿真分析了考虑土壤频变性时土壤电阻率、冲击电流波形等因素对接地装置冲击系数的影响规律。仿真数据分析表明考虑土壤频变性时接地装置的冲击系数与不考虑土壤频变性时的冲击系数相比有一定减小,在高土壤电阻率及陡波前冲击电流作用下其减小程度更明显。

The impulse coefficient is an important parameter to reflect the impact characteristic of grounding device of transmission line tower, accurate calculation of lightning protection is the basis of optimization design and improving the lightning performance of transmission lines. Based on the analysis of soil polarization process, the Visacro-Alipio soil electrical parameters frequency dependence formula is introduced, the grounding device impulse characteristics numerical model is established considering the ground soil electrical frequency degeneration; the simulation analysis effect law of factors such as soil resistivity, impulse current waveform on grounding device considering soil frequency degeneration. The simulation data shows that the impact coefficient of frequency when considering the soil degeneration impact coefficient of grounding device with the consideration of soil degeneration when compared with frequency a decrease in high soil resistivity and steep front impulse currents to reduce the degree is more obvious.