基于噪声子空间分解MUSIC函数的谐波/间谐波检测算法

Harmonic/inter-harmonic detection based on DNS-MUSIC function

针对电力系统中存在的谐波和间谐波问题,提出了基于噪声子空间分解MUSIC(DNS-MUSIC)函数的谐波/间谐波检测方法。利用信号自相关矩阵的特征值分解理论,将信号的自相关矩阵分解为信号子空间和噪声子空间,利用2个子空间的正交性进一步分解噪声子空间,对其进行变换,构造出基于噪声子空间分解的特征多项式(DNS-MUSIC函数),求解该多项式得到信号基波和谐波频率预估计,结合消噪思想检测电力系统信号频率成分,然后利用扩展Prony法检测信号的幅值和相位。通过仿真实验与其他经典算法比较,结果证明了所提算法的可行性、高效性和稳定性。

A detection method based on DNS-MUSIC（Decomposition of Noise Subspace in MUSIC） is presented for the harmonic/inter-harmonic of power system.According to the eigenvalue decomposition theory,the signal self-correlation matrix is decomposed into the signal subspace and the noise subspace.The noise subspace is further decomposed based on their orthogonality,and then transformed to construct its DNS-MUSIC function.The estimated frequencies of fundamental and harmonics are obtained by solving the polynomial of DNS-MUSIC.Combined with the estimated frequency components of power system signal,the extended Prony algorithm is then applied to detect its amplitude and phase of power system signal.Simulation proves the feasibility,efficiency and stability of the proposed algorithm in comparison with other classical algorithms.