实时频谱测量技术在电力设备局部放电检测中的应用

传统的局部放电信号频谱研究通常是采用扫频式的频谱分析仪，其缺点是检测不到当前扫描之外的其它频率上的信号成分，可能漏掉间歇性的频谱信息。对于局部放电信号来说，其发生是随机的、间歇的。因此，扫频式的频谱测量会给局部放电检测带来测量误差，降低测量灵敏度。采用实时频谱测量技术对局部放电信号频谱进行了试验研究。研究发现，通过实时模式下频谱测量，可以捕获扫频频谱仪没有捕获的局部放电频谱信息。同时，测量形成的三维频谱图也能说明局放信号频谱信息的动态变化，这为UHF高频窄带法测量提供了试验依据。

Application of Real-time Spectrum Measuring Technique in Partial Discharge Detection of Power Equipment

The sweep-frequency spectrum analyzer is a conventional means for spectrum research on partial discharge(PD) signals,which can't capture the random and transient spectrum information.But PD signals are just so.As a result,sweep-frequency spectrum measurement is certain to bring measurement error during PD detection and reduce the measurement sensitivity.In this paper,an experimental research on PD signal spectrum by real-time mode is carried out.Results show that the transient PD signal spectrum can be picked up sensitively.Meanwhile,3D spectrogram of PD signals can expediently reflect the dynamic change of the signals.Thus the feasibility of applying ultrahigh frequency(UHF) narrow-band PD monitoring technique to power equipment is established.