基于悬空场磨的空间直流合成电场测量研究

Research on Measuring Space DC Synthetic Electric Field With Ungrounded Rotating Field-mill

随着我国特高压直流输电工程规模的日益增长和低空域的逐渐开放,对输电线路周边的空间电磁环境监测需求日益迫切。然而,缺乏适用于空间直流电场的有效测量仪器和方法。场磨式电场传感器目前被广泛应用于地面直流合成电场的测量。直接将现有的场磨式合成电场传感器悬空应用于空间直流电场测量中可能会引起较大的测量误差。针对此,建立耦合空间电荷和风场因素的电场传感器解析模型和有限元计算模型。通过模型从理论上分析空间电荷累积和风场存在时对场磨式电场传感器测量空间合成电场的影响。并在直流模拟试验线段下搭建了实验平台,设计了4种实验场景。通过实验对比,分析耦合风场因素的空间电荷对悬空场磨式电场传感器的影响。定量研究悬空不接地方式的测量误差,并通过修正算法将该误差控制在一定的范围内。实验结果可以为高压直流输电线路空间电磁环境的准确测量提供参考。

With the increasing scale of UHV DC transmission projects and the gradual opening of low-altitude airspace in China,the demand for space electromagnetic environment monitoring around transmission lines is becoming more and more urgent.However,there is no instrument and method to measure spatial DC electric field effectively so far.Rotating field-mills are widely used in the measurement of ground-level DC synthetic electric field,but applying the existing field-mill to measure spatial DC electric field directly may cause large measurement error.Aiming at this,the electric field sensor analytical model and a finite element calculation model that couple space charge and wind factors to calculate and analyze the influence of space charge on measurement of spatial DC synthetic electric field.In addition,an experimental platform with DC test lines for the four experimental scenarios was established.The effects of space charge with wind on field-mill were analyzed in experimental comparisons,the sensor measurement errors were researched using ungrounded field-mill quantitatively,and the measurement errors were controlled within a certain range through the correction algorithm.The experimental results provide a useful reference for the accurate measurement of the spatial electromagnetic environment of the high-voltage DC transmission line.