特高压同塔双回线路产生的“100 Hz”纯声驻波研究

Study on Standing Wave of “100 Hz” Pure Tone from UHV AC Double-circuit Transmission Lines on the Same Tower

输电线路产生的＂100 Hz＂纯声（嗡嗡声）在雨天比较突出,在线路经过高海拔区域时有增加的风险。为了使居民区尽可能地避开＂100 Hz＂纯声驻波的波峰区域,对特高压同塔双回线路＂100 Hz＂纯声的分布规律进行了研究。采用美国EPRI提出的大雨条件下＂纯声＂声功率产生量,考虑了地面的反射和各相导线产生的声波之间的干涉,建立了输电线路＂100 Hz＂纯声的计算模型,获得了特高压同塔双回输电线路产生的＂100 Hz＂纯声的驻波分布规律;对大雨条件下,＂100 Hz＂纯声的测试数据进行了统计分析,并与计算结果进行了比较。研究结果表明：与A计权声级不同,同塔双回线路逆相序排列时,线路横断面上的＂100 Hz＂纯声分布不对称;幅值振荡缓慢衰减;距离线路较近时,相邻波峰之间距离较小;距离线路较远时,相邻波峰之间距离逐渐增大;距离线路边相数百m后,才会单调下降。

The ‘100 Hz＇ pure tone（hum） from the power transmission line is remarkable in rainy day, and has an increasing risk in high-altitude areas. In order to prevent the residential area from the crest area of the standing wave, we studied the standing wave distribution of ‘100 Hz＇ pure tone. According to the ‘generation＇ of hum under the condition of the heavy rain proposed by American EPRI, considering the ground reflection of sound waves and interference between the sound waves, we established a computational model of standing waves of the pure tone and obtained a distribution rule. Statistical analysis of ‘100 Hz＇ pure tone test data is made under heavy rain conditions, and compared with the calculation results. The calculation results show that, unlike A-weighted sound level, the distribution of ‘100 Hz＇ pure tone of double circuit lines on the same tower with inverse phase sequence is asymmetric and vibration attenuated. The attenuation speed is slower than that of A-weighted sound level; Near transmission lines, the distance between the adjacent peaks is smaller; far from transmission lines, the distance between the adjacent peaks is increased. The value of amplitude decreases monotonically several hundred meters away from transmission lines.