摘要
为解决陡上升/下降沿脉冲方波电压下变频电机绝缘局部放电(PD)检测的信号提取问题,对比研究了高频电流传感器和超高频法测试中局部放电和脉冲电源干扰的时域和频域特性。针对2种信号的不同特征,提出了抑制脉冲电源干扰、提高信噪比的方法。研究结论认为,依据IEC标准进行变频电机局部放电检测时,超高频法在局部放电起始放电电压测试和脉冲信号提取中表现出较高信噪比(S/N)性能,可优先选用。相关系数分析方法可作为局部放电脉冲是否淹没在脉冲电源干扰中的有效判据,联合采用相关系数分析和sym2小波提取技术后,宽频电流测试法仍可在需要的场合作为变频电机绝缘局部放电检测的有效补充。
To extract signals for partial discharge （PD） detection in inverter-fed motors under square voltage pulses that have short rise/fall times, we compared the PD pulses obtained by ultra-high frequency （UHF） tests using high frequency current sensor and disturbance from pulse generator in aspects of their time- and frequency-domain features. According to the different characteristics of the bance and improve the signal to two types of pulses, we proposed a processing method which could suppress distur- noise ratio （S/N）. The analyses indicate that, in the process of detecting PD on inverter-fed motors performed according to IEC standards, the UHF method is preferred for its excellent S/N. The correc- tion analysis can be considered as a useful method for determining overlapping of the PD and disturbance pulses. Meanwhile, high frequency current test can also be used as a supplement to the UHF method, resorting to correlation coefficient and sym2 wavelet extraction technology.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2014年第2期519-525,共7页
High Voltage Engineering
基金
国家自然科学基金(E070202)~~
关键词
变频电机
局部放电
脉冲方波电压
超高频
时频分析
小波分析
inverter-fed motor
partial discharge
impulsive square wave voltage
ultra high frequency
time-frequencyanalysis
wavelet analysis
