CAJ | 학술논문

将希尔伯特-黄变换(HHT)方法用于电气化铁道谐波检测中.由于电气化铁道谐波电压、电流信号中基波能量很大,其它次数的谐波能量相对较小,使得经验模态分解 (EMD)方法在应用中出现模态混叠现象,不能准确地提取任意频率的谐波信号.为改善经验模态分解过程中产生的模态混叠现象,本文采用Yang提出的基于Fourier变换的EMD方法对电气化铁道谐波信号进行筛分.通过该方法可以有效地提取出任意频率的谐波分量,进而计算其Hilbert谱.通过对电气化铁道牵引变电所实测谐波电压、电流数据进行分析,结果表明:利用改进的HHT方法可以得到电气化铁道各次谐波准确的时频分布.最后通过HHT方法计算出各次谐波电压、电流含有率及总谐波电压、电流畸变率,并对计算结果进行分析.HHT 方法为电气化铁道谐波检测与分析提供了一种新的途径.
장희이백특-황변환(HHT)방법용우전기화철도해파검측중.유우전기화철도해파전압、전류신호중기파능량흔대,기타차수적해파능량상대교소,사득경험모태분해 (EMD)방법재응용중출현모태혼첩현상,불능준학지제취임의빈솔적해파신호.위개선경험모태분해과정중산생적모태혼첩현상,본문채용Yang제출적기우Fourier변환적EMD방법대전기화철도해파신호진행사분.통과해방법가이유효지제취출임의빈솔적해파분량,진이계산기Hilbert보.통과대전기화철도견인변전소실측해파전압、전류수거진행분석,결과표명:이용개진적HHT방법가이득도전기화철도각차해파준학적시빈분포.최후통과HHT방법계산출각차해파전압、전류함유솔급총해파전압、전류기변솔,병대계산결과진행분석.HHT 방법위전기화철도해파검측여분석제공료일충신적도경.
Hilbert-Huang Transform (HHT) is applied in detection of harmonics in traction power systems. Mode-mixing appears during sifting by Empirical Mode Decomposition (EMD),because the energy of fundamentals of electric railways are much larger than the other harmonics'. Harmonics cannot be accurately abstracted at any frequencies with EMD. In order to sift the mode-mixing harmonic signals in good mode,an improved method named EMD based on Fourier Transform proposed by Yang is used in this paper. Harmonic components can be abstracted at any frequencies and then the Hilbert Spectrum is obtained by using Hilbert Transform. Actual data of traction substations are analyzed. The results show that the improved HHT method is effective to abstract harmonics at any frequencies and accurate time-frequency distribution of harmonic components can be obtained with this method. Total harmonic distortion (THD) and harmonic ratio (HR) are given in the last. HHT is a new method for harmonic detection and analysis in traction power systems.