The total electric field(TEF) at ground level induced by high-voltage direct current(HVDC) overhead transmission lines is one of the important indexes for evaluating the lines' electromagnetic environment.Based on...The total electric field(TEF) at ground level induced by high-voltage direct current(HVDC) overhead transmission lines is one of the important indexes for evaluating the lines' electromagnetic environment.Based on analyzing the existing TEF sensors and the measurement principle of ion-current density,the influence from ions on TEF measurements is quantitively studied.The results show that the ions generated by the corona from a HVDC transmission line in operation cause errors in the measurement of TEF.This error is determined through analyzing the component of total measuring current on the filed mill's sensing electrode: if no appropriate approach taken,the maximum measurement error reaches up to 4.3%.Furthermore,a method that can eliminate such error,and hence improve the accuracy of TEF sensors is designed.展开更多
有限元法是电场数值计算中普遍采用的一种方法,当求解域内实体较多且结构复杂时,整体模型的区域离散往往难度较大。为此,基于模型的基本几何形态,提出一种针对复杂模型电场数值分析的快速建模剖分方法。以简单2维模型为例,介绍外包区域...有限元法是电场数值计算中普遍采用的一种方法,当求解域内实体较多且结构复杂时,整体模型的区域离散往往难度较大。为此,基于模型的基本几何形态,提出一种针对复杂模型电场数值分析的快速建模剖分方法。以简单2维模型为例,介绍外包区域实体生成及相互位置关系判断算法,结合有限元电场计算时的网格剖分策略,参数化实现模型表面多层网格加密,剖分的效率及质量较高。将该方法应用于特高压直流(ultra high voltage direct current,UHVDC)阀厅设备表面电场计算中,计算结果表明:该方法较子模型法计算所得结果最大误差仅为3.80%,计算效率较子模型法大幅提高。该方法实现了大型复杂模型表面网格精细化控制,对大规模有限元电场计算的快速、准确建模具有一定指导意义。展开更多
基金Project supported by National Natural Science Foundation of China (61273165 51207005).
文摘The total electric field(TEF) at ground level induced by high-voltage direct current(HVDC) overhead transmission lines is one of the important indexes for evaluating the lines' electromagnetic environment.Based on analyzing the existing TEF sensors and the measurement principle of ion-current density,the influence from ions on TEF measurements is quantitively studied.The results show that the ions generated by the corona from a HVDC transmission line in operation cause errors in the measurement of TEF.This error is determined through analyzing the component of total measuring current on the filed mill's sensing electrode: if no appropriate approach taken,the maximum measurement error reaches up to 4.3%.Furthermore,a method that can eliminate such error,and hence improve the accuracy of TEF sensors is designed.
文摘有限元法是电场数值计算中普遍采用的一种方法,当求解域内实体较多且结构复杂时,整体模型的区域离散往往难度较大。为此,基于模型的基本几何形态,提出一种针对复杂模型电场数值分析的快速建模剖分方法。以简单2维模型为例,介绍外包区域实体生成及相互位置关系判断算法,结合有限元电场计算时的网格剖分策略,参数化实现模型表面多层网格加密,剖分的效率及质量较高。将该方法应用于特高压直流(ultra high voltage direct current,UHVDC)阀厅设备表面电场计算中,计算结果表明:该方法较子模型法计算所得结果最大误差仅为3.80%,计算效率较子模型法大幅提高。该方法实现了大型复杂模型表面网格精细化控制,对大规模有限元电场计算的快速、准确建模具有一定指导意义。