摘要
在线测量介质损失角正切 (tanδ)时 ,信号易受干扰 ,畸变严重时 ,即使采用傅里叶变换 (FT)也会出现较大的误差。本文根据小波分析的基本理论 ,结合损失角测量中的波形特征 ,提出了利用小波变换来提取基波信号计算tanδ的检测方法。并对不同特点的小波及FT进行了仿真研究与比较 ,结果验证了该方法的有效性。最后 ,分析了产生误差的原因 。
When on line measuring dielctric loss tangent(tan δ ),much noise exist in sampling signals,and system frequency is not stable.To some extent,the results analyzed by Fourier transform(FT)cant meet the demand on measuring accuracy.Based on basic theory of wavelet transform,according to signals characteristics,an approach is introduced to detect fundamental component in the signal to calculate tan δ .Different wavelets and FT are compared and studied in the simulation tests.The simulation results show the approach is effective.Finally,the reasons of measuring error are analyzed,and better proposals are given to improve calculating accuracy.
出处
《电工技术学报》
EI
CSCD
北大核心
2002年第5期91-95,共5页
Transactions of China Electrotechnical Society
关键词
小波变换
数字化测量
仿真
介质损失
Dielectric loss tangent,wavelet transform,multi resolution analysis
