A new phasor measurement algorithm for distribution network based on interpolation theory

Due to the existence of abundant harmonic source and frequency deviation in distribution network, the accurate phasor result can´t be obtained by conventional Discrete Fourier Transform (DFT) algorithm. In this paper, by using the linear interpolation to modify DFT window length to exactly equal to the fundamental period of signal waveform, the spectrum leakage could be solved. In addition, the duplicated Simpson formula can accomplish Fourier coefficient equivalence for improving precision, so we can get the precise phasor measurement result by comprehensive utilization of above two interpolation in distribution network. The measuring accuracy and noise immunity comparison between the proposed and corrected DFT algorithm is made by MATLAB simulation.