面向高压直流输电接地极设计的土壤电阻率遥感估算

Estimation of Soil Resistivity by Remote Sensing for Grounding Electrode Design of HVDC Transmission

土壤电阻率是影响特高压直流输电接地极极址选择的重要因素,如何快速获取土壤电阻率的空间分布,为接地极极址选择提供参考依据是目前特高压直流输电中面临的重要议题。该文以陕西省榆林市府谷县和山西省部分地区为研究区,通过Sentinel-1、Sentinel-2和SMAP卫星数据联合反演研究区的土壤体积含水量,结合土壤容重获取土壤重量含水量的空间分布,最后利用土壤电阻率的实测数据与遥感重量含水量数据建立估算模型,得出土壤电阻率与土壤重量含水量呈现幂函数形式的拟合关系,据此获取拟接地极极址及周边地区的土壤电阻率空间分布。研究结果表明,通过遥感方式能为大范围内接地极极址的选择提供一种新思路。

Soil resistivity is an important soil property that affects the selection of grounding electrode sites for HVDC transmission.How to quickly obtain the spatial distribution of soil resistivity and provide reference for the selection of grounding electrode sites is an important issue in HVDC transmission.This paper takes part of Shanxi Province and Fugu County,Yulin City,Shaanxi Province as the study area.The Sentinel-1,Sentinel-2 and SMAP satellite data are used to retrieve the soil volumetric water content in the study area,and the spatial distribution of soil gravimetric water content is obtained by combining the soil bulk density with volumetric water content.Finally,the estimation model is established by the field measurements of soil resistivity and soil gravimetric water content estimated based on remote sensing.Through the estimation model,the fitting relationship between soil resistivity and soil gravimetric water content in the form of power function is obtained,and the distribution of soil resistivity at the grounding electrode sites to be selected and its surrounding areas is obtained.The results show that remote sensing can assist in the selection of grounding electrode sites,which provides a new idea for the selection of grounding electrode sites in a large range of areas.