Abstract: HVDC is an important way to solve the electricity transmission over long distances.With the construction of the skeleton of HVDC network in recent years,a new interference anomaly in seismic geoelectric field observation is emerging in China.In this paper,we take Baoji,Qianling and Zhouzhi geoelctric field observations in Central Shaanxi as an example to analyze the changes in shape and characteristics of such anomalies interfered by the Baoji-Deyang ? 500kV DC transmission project,discuss their forming mechanism combined with the basic principles of HVDC,and calculate their possible effects to electric field observations with different distances,conductivities and current into the earth.The results show that,the theoretical and observed geoelectric field values match well when conductivity is 0.01.

Key words: HVDC, geoelectric field observation, interference anomaly, formation mechanism

摘要： 高压直流输电是解决长距离输送电的一种重要手段,近年来,随着中国高压直流输电骨架网的建设,在地震地电场观测中出现了一种新的干扰异常。以关中地区宝鸡、乾陵和周至地电场观测受宝鸡-德阳±500kV直流输电工程影响为例,分析了此类干扰异常的变化形态和特征,并结合高压直流输电的基本原理,对异常的形成机理进行了探讨,定量的计算了不同距离、影响区电导率和高压直流输电入地电流等对地电场观测的可能影响。结果表明,在理想状态下,电导率γ取0.01时理论值与实际观测值基本相符。

关键词: 高压直流输电, 地电场观测, 干扰异常, 形成机理