A high-accuracy algorithm of frequency measurement based on fourier method

Aimed to the existing problems about traditional frequency measurement method, this paper presents a new algorithm based on Fourier frequency measurements. First, according to the error of the original Fourier frequency measurement, the amendatory coefficient is adjusted, an improved method based on Fourier correction coefficient frequency measurement is proposed. Then, because error of the Fourier algorithm is larger when the frequency offset, interpolation algorithms have been proposed based on the true frequency of the signal. In order to improve the signal what contains harmonic component frequency measurement accuracy, iterative of the frequency until the algorithm converges or reach the maximum number of iterations. Finally, the algorithm is verified, the errors of the calculation when there is harmonic component and isn´t harmonic component in the signal are compared. The practice prove that precision of the algorithm is effectively improved, the amount of calculation is significantly reduced, a high precision tracking system frequency is achieved, the requirement of real-time performance of the power system is completely satisfied.