Improved interpolated dynamic DFT synchrophasor estimator considering second harmonic interferences

The interpolated dynamic DFT (IpD ² FT) is one of the most accurate dynamic synchrophasor estimation methods. But it suffers from infiltration from the second harmonic component. In this paper, the estimation errors of the IpD ² FT caused by second harmonic interferences are firstly analyzed. Based on this, an improved interpolated dynamic DFT (IIpD ² FT) synchrophasor estimator that considers second harmonic interferences are proposed. Multiple simulation tests show that, even under large second harmonic interference conditions, the IIpD ² FT is much more accurate than the IpD ² FT.