一种电力系统谐波与间谐波频谱互扰抑制方法研究
惠锦1，董晓峰1，张逸2
(1 国网江苏省电力公司苏州供电公司， 江苏 苏州 215004； 2 国网福建省电力公司电力科学研究院，福建 福州 350007)
摘 要：用离散傅里叶变换分析电力系统谐波和间谐波时，各成分间的频谱干扰是引发分析误差的主要原因。提出了一种基于加窗时域平均的谐波间谐波分离分析法。该方法首先对采样信号进行加窗处理，对加窗后的离散信号进行时域平均，滤波得到拟谐波信号，对拟谐波信号做离散傅里叶变换，得到各次谐波参数。用原始采样信号减去拟谐波信号，得到差分信号，对其时域序列末尾补零加密其频域谱线，峰值搜索求得间谐波参数。该方法能够有效实现谐波和间谐波在时域的分离，抑制其在频域相互干扰；间谐波间的干扰及正负频率成分间的干扰同样可以得到有效的抑制。
关键词：电能质量；谐波间谐波分析；频谱干扰；时域平均；离散傅里叶变换
中图分类号：TM714.3 文献标识码：A 文章编号：1007-3175(2017)09-0019-05
Research on Spectral Interruption Suppression Method for a Kind of Power System Harmonic and Interharmonic
HUI Jin1, DONG Xiao-feng1, ZHANG Yi2
（1 State Grid Jiangsu Power Company Suzhou Power Supply Company, Suzhou 215004, China;
2 State Grid Fujian Electric Power Research Institute, Fuzhou 350007, China）
Abstract: When the discrete Fourier transform (DFT) is used to analyze the power system harmonics and interharmonics, spectral interruptions between different frequency components are the main factor that causes the analysis errors for harmonics and inter-harmonics. This paper proposed a kind of harmonics and inter-harmonics separation analytical approach based on the windowed time domain averaging (TDA). First, each sample point was weighted by the weighing window, then harmonics could be extracted by TDA, and the corresponding parameters could be obtained by DFT. The difference signal was got by subtracting harmonics from the original signal, thus interharmonic parameters could be obtained by zero padding of its time domain sequence to encrypt its frequency domain spectral line and peak searching. This method could effectively separate harmonics and inter-harmonics from the initial signal in the time-domain, strongly restrain the interruptions between haromnics and inter-harmonics, positive and negative frequency components.
Key words: power quality; harmonic and inter-harmonic analysis; spectral interruption; time-domain averaging; discrete Fourier transform
参考文献
[1] 祁才君，王小海.基于插值FFT算法的间谐波参数估计[J].电工技术学报，2003，18(1)：92-95.
[2] 赵文春，马伟明，胡安.电机测试中谐波分析的高精度FFT算法[J].中国电机工程学报，2001，21(12)：83-87.
[3] 郑恩让，杨润贤，高森.关于电力系统FFT谐波检测存在问题的研究[J].继电器，2006，34(18)：52-57.
[4] 王楠，肖先勇，曾颂崎，等.基于插值线性调频Z变换的间谐波分析方法[J].电网技术，2007，31(18)：43-47.
[5] 孙红伟，李梅，袁健华，等.用于电力系统谐波分析的加窗插值FFT 算法研究[J].高电压技术，2004，30(8)：52-55.
[6] 钱昊，赵荣祥.基于插值FFT算法的间谐波分析[J]. 中国电机工程学报，2005，25(21)：87-91.
[7] 曾泽昊，余有灵，许维胜.一种减小频谱泄漏的同步化算法[J].电测与仪表，2005，42(11)：12-14.
[8] 曾泽昊，余有灵，许维胜.基于插值同步算法的频谱泄漏分析与仿真[J].系统仿真技术，2005，1(3)：148-152.
[9] 惠锦，杨洪耕.改进的时域同步插值算法在基于TDA 谐波和间谐波测量中的应用[J].电工技术学报，2008，23(7)：124-129.
[10] LIU Zhongdang, HIMMEL J, BONFIG K.Improved processing of harmonics and interharmonics by time-domain averaging[J].IEEE Transactions on Power Delivery，2005，20(4)：2370-2380.
