RELAX算法在间谐波检测中的应用

Application of RELAX Algorithm on Interharmonic Detection

间谐波是频率非基波整数倍的谐波成分,传统谐波测量方法将会因为非同步采样而产生泄漏误差。为准确测量间谐波,文中提出基于松弛谱估计(RELAX)的检测方法。因为该方法针对复信号进行分析,在检测前需先对采样信号进行希尔伯特变换构成复序列,计算结束后的相位测量结果也要进行修正。由于RELAX算法的复杂度集中在快速傅里叶变换(FFT)处,故相比于其它方法其计算速度是有优势的。最后通过对具体间谐波信号的仿真测量,验证了该方法的有效性和实用性。

Interharmonic is the special harmonic element which is not an integer multiple of the fundamental. Due to the asynchronous sampling problem, serious leakage error may arise with the measurement method for normal harmonics. In this paper, a new approach for sinusoidal parameter estimation based on RELAX（Relaxation algorithm）is presented. To get the correct result, the proposed method depends on two additional steps： the Hilbert Transform of the samples and the phase revise. The method can make the faster measurement in comparison with others since the Fast Fourier Transform（FFT） takes up the main calculation time of the RE LAX. Finally, the simulation results have verified the effectiveness and practicability of the algorithm.