输电线路因电晕放电引起的电子环境问题时有发生,是影响特高压建设的难题之一。可听噪声和无线电干扰水平是研究输电线路电晕特性的重要参数,随着线路运行年限和运行环境的改变,输电线路可听噪声和无线电干扰水平可能发生变化。笔者针对广东南部地区顺江乙线运行年限16年的LGJ400/50老化后导线的电晕电压变化。利用小型电晕笼这一有效、方便的实验平台展开研究,并利用电子显微镜和白光干涉形貌仪对样品表面状况进行观察。文中通过声级计和无线电干扰接收机观测单根LGJ400/50老化导线和同型号新导线在相同施加工频电压下电晕放电过程,并对比两组数据。结果表明,老化后LGJ400/50导线表面状况比新导线明显恶化,表面成分更为复杂;老化后导线可听噪声水平普遍增加1~5dB(A);无线电干扰水平增加最大可达10dB。上述结论为相关部门提供设计、维护建议。
The electromagnetic environment problem, which caused by corona discharge in transmission lines is one of UHV construction difficulty. The audible noise (AN)and radio interference (RI)are important indexes of the corona discharge characteristics, the AN and RI would be changed with the operation time is go on and the atmospheric environment variation. The LGJ400/50 conductor of Shunde-Jiangming, which had been used in South Guangdong Province over 16 years and the new same conductor were used as the test simple with a effective and convenience corona cage in this paper to research the AN and RI feature, while the Scanning Electron Microscope and Phase Shift MicroXAM-3D were used to detect the surface condition of the new and aged conductor. The sound meter and radio interference receiver were taken to detect the corona phenomenon, and the detected values were compared. The experiment results illustrated that the surface conductor of aged conductor worse than new ones, and the composition of the aged conductor surface substance was more complex; the AN value of aged conductor was higher than new ones about 1-5 dB(A); the RI value of the aged conductor was higher than new ones no more than 10 dB. The results may supplied design and maintain suggestions to relevant department.