At the latest, when the reasons for power failures or black outs in which more than one power utility is involved must be analysed, the importance of accurate and precise time stamps of events becomes visible. Experiences from the past show, that aligning data from different utilities can often take much longer than analysing the data itself. But also for protection, automation, and control of electric power systems accurate time references are needed.
With the implementation of the Precision Time Protocol (PTP), defined in the IEEE 1588 standard, a very accurate and secure way to provide time references with accuracies in the sub-microsecond range throughout the power station’s Ethernet network is made available.
In this paper the authors give a general introduction to the PTP standard and its novelties in comparison to existing time synchronization and distribution. They describe implementation and application scenarios in power utilities and inform about the advantages of integrating PTP time synchronisation into a modern IEC 61850 based station control network.