Real-time estimation of single-phase grid voltage frequency using a modulating function based technique

This paper proposes a real-time estimation technique of the single-phase grid voltage fundamental frequency under distorted conditions. The proposed technique relies on a modulating function and an algorithm based on three consecutive samples. The frequency estimation technique is relatively simple, robust and capable of providing accurate estimation of time-varying fundamental frequency from a single-phase grid voltage waveform. It can also reject the negative effects caused by the presence of DC offset and harmonics. Real-time experimental results are presented to confirm the benefits of the proposed estimation technique.