Power System Frequency Estimation by Using a Newton-Type Technique for Smart Meters

Abstract

This paper proposes a single-phase grid voltage fundamental frequency estimation technique for smart meters. The technique relies on a nonlinear Newton-type algorithm and a recursive differentiation filter (NTA–DF). It can reject the negative effects caused by dc offset, harmonics, notches, and spikes. When compared with a NTA technique based on least-squares (NTA–LS), the proposed one reduces matrix dimensions, avoids matrix inversion, and is computationally efficient, thus requiring less hardware and associated cost for real-time implementation. Moreover, unlike the NTA–LS technique, the NTA–DF shows less sensitivity to the presence of harmonics. Simulation and experimental results are presented to verify the performance of the proposed technique.