Impact of GPS Signal Loss and Its Mitigation in Power System Synchronized Measurement Devices

Wide-Area Backup Protection Against Asymmetrical Faults Using Available Phasor Measurements

“…2) Application of unsynchronized phasor measurements: Voltage and current phasors calculated by a PMU or IED at a substation will be all synchronized to the local time reference of that device, which might or might not be aligned with a common time reference in the whole grid. In practice, the time drift of locally-measured phasors caused by the loss of the time synchronisation signal and/or essentially the use of a local time reference can be readily limited to 1.5 s within a 1 sec period [30]. Hence, the phase-angles of pre-and post-fault phasors associated with the same substation remain extremely accurate with respect to each other within the time frame of interest to WABP.…”

Wide-Area Identification of the Size and Location of Loss of Generation Events by Sparse PMUs

“…It should be noted that voltage and current phasors calculated by a PMU in a substation will be all synchronized to the local time reference of that PMU [24]. The phase-angles of phasors associated with a PMU remain extremely accurate with respect to each other within the time frame of interest to LoG event localization [24], [25].…”

Method of amplitude data recovery in PMU measurements that considers synchronisation errors

“…The phase angle difference between PMUs is influenced by the synchronisation error due to GPS signal loss, time synchronisation deviation etc. [26, 31] while the active power and voltage amplitude measurements are not, so (3) is used to check the quality of the VPAD data in Section 2.3.…”

“…[24] showed that the small phase angle error may result in large reactance error in light load. However, the voltage phase angle difference (VPAD) in PMU measurements at both ends of the line may contain deviation due to poor synchronisation [25], GPS signal loss [26], and even spoofing attacks [27]. Furthermore, the long‐term deviation of VPAD data is observed in [28], and the VPAD data jumping is observed in [29].…”