不同辐射源瞬态电磁信号辐射场特性研究

Properties of transient electromagnetic signals radiation field from various radiation sources

为研究不同辐射源瞬态电磁辐射信号辐射场特性,建立了圆柱形导体传输线模型,基于频域法对电晕放电的远场辐射场进行了理论计算,计算结果表明放电信号的时域波形衰减振荡时间随导体尺寸的增加而增大,辐射场频谱高频分量减少,且随着导体长度的增加,辐射场振荡频率逐渐降低.设计瞬态电磁辐射信号测试实验,验证了理论计算结果.同时,实验采集了摩托车火花塞打火时的时域与频域信息,结果表明火花塞放电时域波形与电晕放电相近,但频谱差别很大,火花放电频谱能达到GHz以上.

To research the properties of transient electromagnetic signals radiation field from various radiation sources,the cylindrical conductor transmission line is modeled.The far radiation field of corona discharge is calculated based on frequency domain method.The calculated results indicate that as the length of conductor elongating,attenuation time of discharge signal increases,and the discharge components in high frequency decrease.The measurement experiment of transient electromagnetic signals is conducted,which verifies the calculated results.Meanwhile,the time domain and frequency domain frequency information of sparking from motorcycle spark plug are measured.The measured results show that properties of spark discharge are the same as corona,but different in frequency spectrum.The frequency spectrum of discharge could reach upon GHz.