基于改进的单通道对称正交化FastICA的间谐波检测方法

针对电力系统中间谐波检测的问题,提出一种基于改进的单通道对称正交化FastICA的间谐波估算算法.该算法首先对单通道电力系统混合信号进行循环平移,构造出多道观测信号,通过主成分分析法对其进行降维处理;其次利用改进的对称正交化FastICA算法对多个独立成分并行估计,分离出基波、谐波和间谐波信号频率;最后应用最小二乘法对谐波和间谐波幅值和相位进行估计.仿真结果表明,该方法可以较准确地检测出各次谐波和间谐波的频率、幅值和相位,较之FastICA算法,该算法不需任何先验知识,收敛速度快,检测精度高.

Inter-Harmonic Detection Based on Improved Single Channel and Symmetrical Orthogonalization FastICA

To solve the problem of power system inter-harmonic detection,an inter-harmonic estimation algorithm based on improved single-channel symmetric orthogonalization FastICA is proposed.Firstly,a multi-channel observed signal is formed by cycle-spinning of single channel mixed signal from power system,then dimension of the multi-channel signal is reduced by principal component analysis.Secondly,the frequencies of fundamental harmonic and inter-harmonic are separated by using the improved symmetry orthogonalization FastICA algorithm.Lastly,the amplitude and phase of the harmonic and inter-harmonic are obtained by using the least squares method.The simulation results show that this method can detect the frequency,amplitude and phase of all the harmonics and inter-harmonics accurately.Compared with the FastICA algorithm,this method has the characteristics with no need of any prior knowledge,and fast convergence and high detection precision.