An Experimental Characterization of Time of Arrival Accuracy for Time Synchronization of Medium Voltage Smart Grid Solutions

The time synchronization of smart grid devices is a critical feature for the successful application of advanced grid monitoring and control techniques. Synchronization mechanisms based on the accurate estimation of the Time of Arrival (ToA) of network messages - sent over power line cables - are a promising solution to achieve synchronization tasks over distribution lines. In this paper, a chirp-based synchronization technique over the Medium Voltage (MV) grid has been proposed and characterized. Such approach has the benefit of not requiring the installation of a dedicated infrastructure, thanks to the exploitation of power distribution lines for the transmission of time synchronization data. The effectiveness of the approach has been experimentally evaluated on a simplified MV line available in a testing laboratory. Although, the tested chirp has a limited frequency bandwidth (80 kHz), the maximum variation of the ToA estimation is on the order of 3.5 μs, which fulfills the requirements of most smart grid applications.