摘要
本文在分析了电力变压器局部放电在线监测中的干扰及局放信号特性的基础上,对局放信号及干扰的功率谱进行了研究,提出了利用频域分析识别周期性干扰,并通过数字陷波滤波器抑制周期性干扰的方法。以时频功率谱为基础,研究了自相关函数的小波变换及与时频功率谱的关系,提出了利用小波变换从白噪声中提取局放信号的方法。
this paper, we analyze the interferences in PD monitoring on line and the characteristics of the inter ferences and PD signal. The interferences and PD signal's power spectrums are studied. The method of distingushing and liminating periodic interferences through frequency domain analysis and digital wave trap filter is propossed. The concept of time--frequency power spectrum is presented. The relations between the time-- frequency power spectrum and the wavelet transform of auto--correlation function is also studied. The method of PD signal's drawing from white noise is presented.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
1999年第3期242-243,267,共3页
Chinese Journal of Scientific Instrument