计算机工程与应用
計算機工程與應用
계산궤공정여응용
Computer Engineering and Applications
2015年
20期
198-202,212
,共6页
微电网%谐波检测%希尔伯特-黄变换(HHT)%经验模态分解%瞬时频率
微電網%諧波檢測%希爾伯特-黃變換(HHT)%經驗模態分解%瞬時頻率
미전망%해파검측%희이백특-황변환(HHT)%경험모태분해%순시빈솔
microgrid%harmonic detection%Hilbert-Huang Transform(HHT)%empirical mode decomposition%instanta-neous frequency
为解决微电网谐波、突变等复杂非平稳信号的精确检测问题,提出一种基于Hilbert-Huang变换(HHT)的微电网谐波检测与时频分析方法。该方法采用保形分段三次埃尔米特插值法拟合极值点曲线,对谐波信号进行经验模态分解(EMD),得到有限个固有模态分量(IMF)并进行Hilbert变换,最终计算各个IMF分量的瞬时频率和瞬时幅值,实现微电网谐波等非平稳电能信号的时频特性精确检测。仿真结果表明,该方法能够快速、准确地获取谐波信号频率成分、幅度及电压突变时刻。相对于FFT变换及传统HHT方法具有较高的精度和时域区分特性,可满足微电网谐波微机检测的工程应用需求。
為解決微電網諧波、突變等複雜非平穩信號的精確檢測問題,提齣一種基于Hilbert-Huang變換(HHT)的微電網諧波檢測與時頻分析方法。該方法採用保形分段三次埃爾米特插值法擬閤極值點麯線,對諧波信號進行經驗模態分解(EMD),得到有限箇固有模態分量(IMF)併進行Hilbert變換,最終計算各箇IMF分量的瞬時頻率和瞬時幅值,實現微電網諧波等非平穩電能信號的時頻特性精確檢測。倣真結果錶明,該方法能夠快速、準確地穫取諧波信號頻率成分、幅度及電壓突變時刻。相對于FFT變換及傳統HHT方法具有較高的精度和時域區分特性,可滿足微電網諧波微機檢測的工程應用需求。
위해결미전망해파、돌변등복잡비평은신호적정학검측문제,제출일충기우Hilbert-Huang변환(HHT)적미전망해파검측여시빈분석방법。해방법채용보형분단삼차애이미특삽치법의합겁치점곡선,대해파신호진행경험모태분해(EMD),득도유한개고유모태분량(IMF)병진행Hilbert변환,최종계산각개IMF분량적순시빈솔화순시폭치,실현미전망해파등비평은전능신호적시빈특성정학검측。방진결과표명,해방법능구쾌속、준학지획취해파신호빈솔성분、폭도급전압돌변시각。상대우FFT변환급전통HHT방법구유교고적정도화시역구분특성,가만족미전망해파미궤검측적공정응용수구。
In order to solve the problem to accurately detect complex non-stationary signals, such as micro-grid harmonic and mutation, a method based on Hilbert-Huang Transform(HHT)is presented. The method is about harmonic detection and time-frequency analysis for micro-grid. It fits extreme value curve by adopting shape-preserving piecewise cubic Her-mite interpolation, and implements Empirical Mode Decomposition(EMD)on harmonic signals, then a finite number of Intrinsic Mode Components(IMF)are obtained, and Hilbert transformation is conducted. The instantaneous frequency and amplitude of each IMF components are calculated finally. The time-frequency characteristics of micro-grid harmonic in non-stationary power signals are detected accurately. The simulation results show that the method can quickly and pre-cisely obtain the harmonic signal frequency components, amplitude and voltage mutation time. Compared with FFT and traditional HHT methods, it has higher accuracy and obvious time distinguishing feature, which meets the engineering application requirements for micro-grid harmonic computer detection.