基于自适应动态模态分解的间谐波参数检测

Inter Harmonic Parameter Detection Based on Adaptive Dynamic Mode Decomposition

摘要: 电力系统中的间谐波污染问题正在从多个方面危害电力系统的正常运行。针对电力系统中存在间谐波的电压信号分解和参数识别问题，本文提出了自适应动态模态分解法。首先利用本文提出的误差系数法和能量法确定信号输入矩阵的系数；接着利用动态模态分解法分解信号，得到模态分量；最后通过双谱线插值的FFT算法计算瞬时幅值和瞬时频率，确定间谐波分量的参数。经过本文实验验证，此方法能够精确识别分解信号中的间谐波分量，在参数识别时的精度较高，在处理基频偏移、密集分量时的表现较好，且克服了传统方法存在的模态混叠问题，在精度上也高于传统识别算法，同时具有较好的噪声鲁棒性。在搭建实验平台进行实验和检测实际信号时，也体现了很好的实用性。

Abstract: The problem of inter harmonic pollution in the power system is endangering the normal operation of the power system from multiple aspects. This paper proposes an adaptive dynamic mode decomposition method to address the problem of voltage signal decomposition and parameter identification in the presence of interharmonics in the power system. Firstly, the error coefficient method and energy method proposed in this article are used to determine the coefficients of the signal input matrix; then use the dynamic mode decomposition method to decompose the signal and obtain modal components; finally, the instantaneous amplitude and frequency are calculated using the FFT algorithm with double spectral line interpolation to determine the parameters of the interharmonic components. After experimental verification in this article, this method can accurately identify the interharmonic components in decomposed signals, with high accuracy in parameter identification and good performance in dealing with fundamental frequency offset and dense components. It also overcomes the mode mixing problem of traditional methods and has higher accuracy than traditional identification algorithms. At the same time, it has good noise robustness. The practicality of building an experimental platform for conducting experiments and detecting actual signals has also been demonstrated.