A New Strategy for Power System Harmonic Analysis Based on N=L×10M-Point DFT

Abstract

This paper introduces a new strategy for power systems harmonics analysis based on N=L×10 M -point DFTs. When the fundamental frequency of a power system signal is 50 Hz, a sampling frequency 2000Hz is selected, N=L×10 M -point DFTs can reduce spectral leakage and obtain high accuracy harmonic parameters. The simulation results in MATLAB show that the strategy are feasible, and comparing with the harmonic analysis method based N=2 M -point DFTs in radix-2 or radix-4 FFT algorithm, the harmonic analysis method based N=L×10 Mpoint DFTs has the obvious superiority. This new strategy maybe open up a new ideas for power system harmonic analysis.

Fast 10-Point DFT Algorithm for Power System Harmonic Analysis

“…The best algorithm was a PFA with radix-10. The spectral leakage can be reduced, and the computed harmonic parameters are more approximate to the actual value, as shown in [37,39]. Therefore, the proposed radix-10 DFT can be efficient for use in harmonics analyses in power systems.…”

“…Using a mixed-radix in an electric power system is not a new solution [51]. For the harmonic analysis of a 50 Hz or 60 Hz signal, it is convenient to assume N = 10 M N 2 and N 1 = 10 M , which solves the problem of sampling a non-integral number of periods and thus spectral leakage [37,39]. If we let M R1 , A R1 , S R1 , and M R2 , A R2 , S R2 denote the number of real multiplications, additions, and assume right-shiftings by 1 bit of the N 1 and N 2 -point DFT, then the total number of real multiplications and additions of the (N = N 1 N 2 )-point DFT in the DFA [49] are…”

“…In [37], a solution to this problem by using N = L × 10 M -point DFTs was proposed to reduce spectral leakage and provide high-accuracy harmonic parameters. An original approach to computing a 10-point DFT was described in [38,39].…”