【摘要】 随着特高压直流输电工程的建设,直流输电线路对地磁台站地磁观测的影响是目前迫切需要解决的问题。基于地磁观测仪器的工作原理,分析了直流线路影响地磁观测的原因,认为直流线路上承载电流产生的磁场附加到仪器观测的空间磁场导致了对地磁观测的干扰。根据线路电流流动方向、线路和地磁台站的相对位置,研究了直流线路影响地磁观测的特点。建立了无限大均匀土壤和分层土壤情况下的入地电流磁场计算模型和极导线电流磁场模型,计算了不同距离点处的磁场幅值。分析结果表明,直流线路主要影响地磁Z分量的观测,具体影响幅度和线路不平衡电流大小有关。在计直流线路对地磁观测的干扰时,可不考虑大地土壤情况以及入地电流在大地内的传播情况。更多还原

【Abstract】 The influence of DC transmission lines on the geomagnetic observation is the urgent problem.Based on the principle of geomagnetic observation instrument,the influence is analyzed,and it is believed that the magnetic field of current on DC transmission line which is attached to the observed magnetic field of geomagnetic observation instrument is the main reason.According to the direction of current on DC transmission line and the relative position between geomagnetic station and transmission line,the influence characteristic is researched.A calculation model for magnetic field of current on polar conductor and a model for ground current in infinite homogeneous soil and in layer soil around earth electrode field are established.Calculated results of the magnetic field strength at different distance from earth electrode and polar conductor show that main influence of DC transmission line on geomagneic observation is its influence on Z component of geomagnetic,and the influential degree is related with imbalance current of DC transmission line.During the calculation of the influence,the soil conditions and the ground current could be ignored.更多还原