Application of All Phase FFT Algorithm in Harmonic Measurement

The result of the traditional FFT algorithm can be corrected through some methods,such as the FFT window interpolation algorithm,the ratio method and so on.However,the test accuracy is limited and there is one larger measurement error that affect the accuracy of harmonic analysis.Based on the method of discrete spectrum correction,this paper studies a new correction method-All phase FFT algorithm.This algorithm can automatically search for the peak of each harmonic,and it can effectively improve the power of the harmonic frequency,phase and amplitude accuracy.In this paper,with the matlab tool,comparing the two methods,the results show that the All phase FFT algorithm is simple,practical and high precision,especially for the detection of inter-harmonics.It can effectively prevent spectral leakage and has a strong anti-interference ability.