  This paper proposes a novel phase identification method for distribution
networks where phases can be severely unbalanced and insufficiently labeled.
The analysis approach draws on data from high-precision phasor measurement
units (micro-synchrophasors or uPMUs) for distribution systems. A key fact is
that time-series voltage phasors taken from a distribution network show
specific patterns regarding connected phases at measurement points. The
algorithm is based on analyzing crosscorrelations over voltage magnitudes along
with phase angle differences on two candidate phases to be matched. If two
measurement points are on the same phase, large positive voltage magnitude
correlations and small voltage angle differences should be observed. The
algorithm is initially validated using the IEEE 13-bus model, and subsequently
with actual uPMU measurements on a 12-kV feeder.
