基于可听噪声时域测量的正极性单点电晕放电声压级分析  

Sound Pressure Level of the Audible Noise from Single Positive Corona Source Based on the Time Domain Measurement Results

作　　者：卢铁兵[1] 张娣[1] 李学宝[1] 

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,北京102206

出　　处：《高电压技术》2015年第3期971-978,共8页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2011CB209402);中央高校基本科研业务费专项资金(13XS07)~~

摘　　要：为了使可听噪声的时域结果直接应用于噪声评价中,根据声级计的基本原理和直流电晕放电产生可听噪声的随机性特点,叙述了将可听噪声时域测量结果转化为声压级的方法,即采用功率谱分析方法来计算可听噪声声压的有效值,同时实现对噪声信号进行时间计权、A计权及倍频分析等,从而实现了由时域数据获得频域声压级的目的。基于实验室内搭建的单点电晕放电可听噪声测试平台,获得了单点电晕放电产生的可听噪声的时域波形,将该方法与Labview噪声分析工具箱的分析结果进行对比,验证了本文方法的正确性。最后对单点电晕放电产生可听噪声的频域特性及声压级特性进行了分析。研究结果表明,单点直流电晕放电产生的可听噪声的声压级在可听的频率范围内(20 Hz^20 k Hz),随着电压增加而有所增加;电晕噪声在高频段(1 k Hz以上)内的A计权声压级相对较大。研究方法和所得结论可为对电晕放电产生可听噪声特性的深入研究奠定基础。The time domain results of the audible noise can be used in the evaluation of the noise level directly at present, therefore, we put forward a method for transferring time domain results into the sound pressure level in frequency domain based on the principle of sound level meter and randomness nature of the audible noise from DC corona discharge. In this method, the power spectrum is used to calculate sound pressure values and the time weighting, and to realize the A-weighted analysis of the audible noise signal. The validity of the presented method is demonstrated through comparing with the calculated results based on Labview program. Moreover, the method is applied to analyze the characteristics of audible noise caused by single corona source under a positive voltage. The frequency domain characteristics and the sound pressure level characteristics of the audible noise are analyzed. The result reveals that the level of sound pressure of the audible noise generated from single-point DC corona in discharging increases as the voltage increases, which is between 20 Hz and 20 k Hz. The A-weighted sound pressure level of corona noise at high frequency（above 1 k Hz） is higher. The results can lay a foundation for the future research on characteristics of audible noise produced by the corona discharge.

关 键 词：时域测量 频域分析 时间计权 1/3倍频分析 频率计权 功率谱 

分 类 号：TM751[电气工程—电力系统及自动化]