特高压直流长、短输电线路无线电干扰的转换关系分析

Analysis on Radio Interference Transformation Relation Between Long and Short UHVDC Transmission Lines

研究特高压直流长、短输电线路的无线电干扰转换关系,对于将特高压直流试验基地建设的试验线段和电晕笼内导线的试验结果用于预测实际特高压输电线路的无线电干扰有重要意义。推导了由无线电干扰激发函数表示的任意长度、任意终端阻抗输电线路上无线电干扰的计算公式。该计算公式在几种情况下简化后与国外文献结果的对比,可说明其可靠性。在此基础上,导出了中国特高压直流试验基地建设的试验线段和电晕笼内导线适用的长、短线无线电干扰转换关系。无限长线路的无线电干扰等于试验线段和电晕笼内导线的无线电干扰频率特性曲线极小值包络线乘以相应的转换系数。该研究结果对特高压直流输电工程的电磁环境评估有一定的参考作用。

The radio interference（RI） measurements made on the test lines and the lines in the test cages in the UHVDC test base can be used to predict the RI performance of the long lines,which makes it significant to study the RI transformation relation between long and short lines.The RI formula of the transmission line with arbitrary length and arbitrary terminated impedance expressed by the RI excitation function was derived,and it was verified by comparison with the existing results under certain circumstances.Furthermore,the RI transformation relations between long and short lines appropriate for the test line and the line in the test cage in the UHVDC test base of China were obtained.The RI current of the long line can be estimated by the envelope of minima of the RI current frequency spectrum of the test line or the line in the test cage multiplied by the corresponding transformation factor.The results can provide reference for the electromagnetic environment evaluation of UHVDC transmission projects.