An Improved FFT Algorithm and Its Application in the Measurement of Grounding Resistance

摘要

For the problems of noise and clutter interference in the measurement of grounding resistance, the article designs a grounding resistance measurement method based on an improved FFT algorithm. We deduce the harmonic amplitude correction formula which can more accurately measure the frequency of the interference signals and the amplitude of the effective signals, and thus improve the measurement accuracy of grounding resistance. This paper also devises a grounding resistance measurement scheme combining the algorithm and the variation-frequency method. The simulation results and the validation of experimental data show that, the algorithm evidently reduces the noise and improves the measurement precision. The algorithm is of high practical value to the grounding resistance measurement.