Study of harmonic analysis based on improved discrete Fourier transform

The continuous expanding of power grid scale brings great a large number of nonlinear elements, which produce the harmonic problem. Discrete Fourier Transform(DFT) is an effective tool for harmonic analysis, but there are hidden the troubles of aliasing, picket fence effect and spectral leakage in DFT, which affect the accuracy of the harmonic analysis. In this paper, DFT has been improved to avoid spectral leakage. This improved algorithm has been experiment validated that it can effectively suppress spectral leakage, creates a balance between accuracy and complexity, and can be applied to a variety of devices.