摘要
该文对变压器振动情况进行理论分析,设置绕组短路故障,在正常和故障两种状态下进行多次实验,测量正常和故障两种状态下的振动信号。提出一种基于小波-高低频包络谱能量分布提取振动信号特征并确定绕组匝间短路故障阈值的新方法。首先应用小波变换对振动信号进行降噪处理,然后与希尔伯特变换结合,提取振动信号的低频和高频包络,最后对包络信号进行谱分析和能量特征提取,比较正常运行状态和短路故障状态下的能量分布。通过实验得到了故障阈值,表明能量法可用于故障的监测和诊断。
This paper makes a theoretical analysis of transformer vibration and conducts experiments on a transformer for several times under the normal condition and winding short-circuit condition. The winding short-circuit is a man- made fault in this experiment. A new method based on the wavelet-envelop spectrum energy distribution for extracting the vibration signals characteristics and establishing the threshold of winding short-circuit fault is presented. Firstly, the vibration signals are denoised by the method of wavelet transform. Then the envelope spectra of low frequency and high frequency signals are extracted by wavelet transform combined with Hilbert transformation. Lastly, the spectral analysis and energy characteristics extraction for envelope signals are completed, and the energy distribution are com- pared on the normal condition and short-circuit condition. The threshold of transformer winding short-circuit fault is obtained through the experiments and the results show that this method can be used to monitor and diagnose the trans- former winding short-circuit fault.
出处
《电力系统及其自动化学报》
CSCD
北大核心
2013年第2期77-82,共6页
Proceedings of the CSU-EPSA
基金
国家电网公司科技资助项目(2011-0810-2251)
关键词
变压器
振动
绕组短路
小波变换
包络谱
transformer
vibration
winding short-circuit
wavelet transform
envelope spectrum
