中文摘要：

输电线路的可听噪声是发展特高压直流输电需要解决的关键技术问题之一。特高压直流试验线段和电晕笼是研究实际线路可听噪声的重要试验设施。研究特高压直流长、短输电线路可听噪声的转换关系,对于利用特高压直流试验基地建设的试验线段和电晕笼的试验结果预测实际特高压输电线路的可听噪声有重要意义。推导了由可听噪声产生功率表示的任意长度输电线路下方地面各位置处可听噪声的计算公式,并由此得出直流长、短输电线路可听噪声之间的关联关系。当单回直流试验线段的长度大于测量点到正极导线距离的10倍、测量点在线路纵向上偏移中心点不超过线路总长的20%时,可近似认为试验线段下可听噪声的测量结果为实际无限长线路相同位置处的可听噪声水平。

英文摘要：

Audible noise （AN） of transmission lines is one of the key technical problems to be solved for the development of UHVDC power transmission. The UHVDC test line and corona cage are important experimental facilities for the research on AN of actual transmission lines. It is crucial to research the AN transformation relation between long and short UHVDC transmission lines for predicting the AN level of actual UHV transmission line by experimental results of test line constructed in UHVDC test base. The calculation formula for AN level at different positions beneath transmission line with arbitrary length, which is expressed by the acoustic power of the corona sources, is derived and it follows that the incidence relation between AN level of long UHVDC transmission line and that of short transmission line is attained. Under the measurement conditions that the length of single-circuit UHVDC test line is larger than 10 times of the distance from the measuring point to positive polar conductor and the offset of measuring point in longitudinal direction of transmission line is not larger than 20% of total length of the test line, the measured AN level beneath the test line can be approximately regarded as the AN level at the same position of actual infinite long lines.