A Fast Power Grid Frequency Estimation Approach Using Frequency-Shift Filtering

In this letter, a fast frequency estimation approach is proposed using frequency-shift filtering. The original sampled signal is first frequency-shifted to 0 Hz nearby via multiplying a reference signal. Then, a convolution average filter is applied on the shifted signal to eliminate the spectral interference caused by asynchronous sampling. Finally, the frequency of power system can be estimated using the phase difference between arbitrary two points of the filtered signal. The approach has major advantages of low computational burden and strong anti-noise performance, which makes it appropriate for high precision and reporting rate frequency measurement in embedded systems. Comprehensive simulations are conducted to validate the accuracy and efficiency of the proposed approach.