摘要
于经验模式分解（Empirical Mode Decomposition,EMD）瞬时频率估计是一种新的时频分析方法,它具有良好的时频局部化特征,适用于电力系统故障分析。它是通过EMD方法提取非平稳信号的本征模态函数（Intrinsic Mode Function,IMF）,再进行Hilbert变换即可得到各信号分量的瞬时频率,对其进行分析即可检测到信号发生故障和扰动的准确时刻。此方法从根本上摆脱了傅立叶分析的局限性,通过对中性点不接地系统中由单相接地故障激发铁磁谐振的仿真,验证了此方法的有效性。
Instantaneous frequency estimate based on EMD is a new analysis method with good time-frequency localization characteristic,so it is suitable for fault analysis of system.The signal is decomposed into intrinsic mode function by EMD.Then instantaneous frequency are obtained from it.Thus the time of the disturbances caused by fault can be detected accurately through them.The method gets rid of localization of Fourier transform radically.The validity is confirmed by simulation of ferromagnetic resonance occurred in neutral point unearthed system,which is excited by single phase grounding fault.
出处
《网络安全技术与应用》
2010年第6期49-51,共3页
Network Security Technology & Application
基金
河南省自然科学基金项目（批准号：2008A470010）资助
关键词
瞬时频率
经验模式分解
电力系统
铁磁谐振
instantaneous frequency
empirical mode decomposition
power system
ferromagnetic resonance
