Accurate and fast synchrophasor estimator for distribution networks

Abstract

In this paper, we propose a synchrophasor estimator which can meet the M and P class requirements of the IEEE standard C37.118.1 simultaneously. Meanwhile, the phase error of the estimator is always smaller than 0.05 degrees, which makes it applicable in distribution networks. The errors of the interpolated dynamic discrete Fourier transform (IpD2FT) due to interharmonic interferences are investigated. Then the optimal frequencies where the IpD2FT has the smallest interharmonic interference are obtained. To achieve higher accuracy, the Taylor–Fourier multifrequency (TFM) model-based method is used to estimate and then eliminate the interharmonic component further. Concerning response time requirements, robust thresholds for transient detection are obtained based on numerous simulations, and the Kaiser-based IpD2FT is used to meet the corresponding limits. Canonical tests stated in the IEEE standard C37.118.1 and specific tests which could occur in distribution networks are both carried out to verify the performance of the proposed method.