Detecting synchrophasors computed over fault/switching transients

Abstract

Faults and switching operations often cause step changes in voltage and current waveforms. A fault/switching transient synchrophasor is computed over a window of pre- and post-fault/switching samples. Many synchrophasor applications are not designed to use these transient synchrophasors. So, there is a need to detect fault/switching transient synchrophasors. A robust algorithm is proposed to detect synchrophasors computed over switching/fault transients. The proposed algorithm runs in phasor measurement unit. The proposed algorithm performs satisfactorily in the presence of noises, harmonics, off nominal frequencies, decaying DC and missing/bad samples. The proposed algorithm can detect fault/switching transient synchrophasors caused by smaller or larger disturbances. The proposed algorithm is simple, non-iterative and mainly needs additions. Possible applications of the proposed algorithm are also discussed.