Accuracy Analysis of the Multicycle Synchrophasor Estimator Provided by the Interpolated DFT Algorithm

Abstract

This paper investigates the accuracy of synchrophasor estimators provided by the interpolated discrete Fourier transform (IpDFT) algorithm under both steady-state and dynamic conditions when two- or three-cycle length observation intervals are considered. According to the IEEE Standard C37.118.1-2011 about synchrophasor measurements for power systems, the estimation accuracy is expressed by the total vector error (TVE). The effect on the estimation accuracy of different window functions, observation interval lengths, and processed DFT samples is analyzed through computer simulations. It is shown that most of the performance requirements specified in the Standard can be satisfied with a proper selection of the algorithm characteristics. Also, the performances of the proposed synchrophasor estimators and state-of-the-art estimators recently proposed in the scientific literature are compared and discussed. Some experimental results are presented in order to confirm the performed analysis.