基于引入松弛因子的改进式单通道FastICA的间谐波检测方法

Inter-harmonic detection method based on improved single channel FastICA with relaxation factor

为改善高阶FastICA间谐波检测算法对初值敏感性的问题,提出一种基于松弛因子的改进式单通道FastICA间谐波检测方法。首先,对单通道信号延迟处理构造观测信号矩阵,采用主分量分析法(PCA)对其降维处理。其次,利用最速下降法求得松弛因子,并对迭代初值进行修正。然后,通过对称正交化FastICA算法对观测信号进行分离,得到基波、谐波和间谐波的频率,借助最小二乘法估计出相应的幅值和相位。仿真结果表明,该算法不仅能够较精准地检测到间谐波及其相关参数,同时降低了高阶算法对初值的敏感性。

To solve the initial values impact of the inter-harmonic detection based on high order FastICA, an inter-harmonic detection method based on improved single channel FastICA with relaxation factor is proposed. Firstly, a multi-channel signal observed is formed by cycle-spinning of single channel mixed single, then dimensionality of the multi-chatmel signal is reduced by principal component analysis. Secondly, by using the relaxation factor which is calculated with the steepest descent method to modify the iterative initial value. Lastly, the symmetry orthogonalization FastICA algorithm is applied to get the frequency of inter-harmonic, and the inter-harmonic amplitude and phase is accurately obtained by using the least squares method. Simulation results show that the algorithm can accurately obtain the inter-harmonic frequency as well as the corresponding harmonic parameters, and also reduce the sensitivity to initial value of the higher order algorithm.