基于apFFT-AMD的密集频率谐波/间谐波检测

针对电力谐波信号中含有密集频率的谐波/间谐波问题，提出全相位快速傅里叶变换（apFFT）与解析模态分解法（AMD）相结合的检测方法. 由于AMD在分解前需要确定信号中各个频率成分，应用apFFT对待分析信号进行频谱分析，得到频谱中各个频率的值；通过apFFT相位谱的平坦特性来判断信号中是否含有密集谱频率成分，获得密集频谱谐波/间谐波频率的大概位置，若含有密集频谱成分，对信号中的密集频段使用量子粒子群进行优化，寻找最佳的二分频率；通过各个频率成分之间的二分频率，利用AMD方法将电力谐波信号分解为一系列的单频信号分量，以完成含有密集频率的谐波测量. 与希尔伯特-黄变换法（HHT）相比，该方法对于含有密集频率的谐波/间谐波信号分解效果更好. 仿真和实验结果都表明了该方法的有效性和准确性.

Dense frequency harmonic/interharmonic detection based on apFFT-AMD

A combining detection method of all-phase fast Fourier transform (apFFT) and analytical mode decomposition was proposed aiming at the harmonic/interharmonic problem with dense frequency in power harmonic signals. Since AMD needs to determine the frequency components in the signal before decomposing, apFFT was used to perform spectrum analysis on the analyzed signals to obtain the values of the frequencies in the spectrum. The flat characteristics of the apFFT phase spectrum were used to determine whether the signal contains dense spectrum frequency component, and the approximate position of dense spectrum harmonic/interharmonic frequency was obtained. If there were dense spectral components, the dense spectrum segment of the signal was optimized by using quantum particle swarm to find the best binary frequency. The power harmonic signal was decomposed into a series of single-frequency signal components through the binary frequency between each frequency component by using AMD method in order to complete the measurement of harmonics with dense frequency. The method is better for the decomposition of harmonic/interharmonic signals with dense frequency compared with Hilbert-Huang transform (HHT) method. The simulation and experimental results showed the effectiveness and accuracy of the proposed method.