为得到放电针电晕放电辐射场的时域和频域特征,利用组建的静电放电测试系统在室外背景噪声研究的基础上实验研究了电晕放电辐射信号,分析了不同极性和大小的电压、天线极化方向、接收距离、放电针形状、温湿度对电晕放电辐射信号波形和频谱的影响.实验表明,电晕放电信号波形陡峭,上升时间从几ns到20几ns;频谱成钟型连续谱,集中在20~100 MHz;不同极性,信号波形不同,且正电晕信号幅值高于负电晕;电晕放电辐射场一般为垂直极化,强度反比于接收距离;相对湿度较大时测到的信号幅值较大.
In order to get the characteristics of time domain and frequency domain of fields radiated from corona discharge, the back noise outside of laboratory is researched firstly, and then the characteristics of signal radiated from corona discharge are experimentally researched. The effect of different factors, such as different polarity of potential, direction of polarization of antenna, receiving distance, the shape of discharging needle, temperature and humidity , on the waveform and spectrum of signal radiated from corona discharge. The experimental results show that the waveform of signal radiated from corona discharge has a steep rising edge; the spectrum of signal radiated from corona discharge is continual, of which frequency range is from 20 to 100MHz; when the polarity is different, the waveform of signal radiated from corona discharge is different, and the amplitude of signal of positive corona is higher than of negative corona; the politicization mode of fields radiated from corona discharge is vertical; the intensity of fields radiated from corona discharge is inversely proportional to the receiving distance; the higher the relative humidity is, the higher the amplitude is. The above results are very important to the research and control of corona discharge that happens on the high-voltage electrical apparatus or EHV transmission line, etc.