Research on Differential Protection Phase Synchronization of Distribution Networks Based on 5G Communication

Abstract

Fiber laying costs are high and it limits the largescale promotion of differential protection in distribution networks.5G communication has characteristics of high reliability and low latency which provides new possibilities for this difficulty. This paper proposes an automatic phase synchronization method based on voltage when the system is normal. Based on the mentioned voltage, this method uses ping pong or historical data to find the same cycle of the different DTUs firstly, and then uses the voltage phase data to synchronous waveforms. After two compensations, it can realize accurate phase synchronization. Also, it only needs 5G communication instead of optical fiber or GPS, the synchronization accuracy is less than 3us.It can be used in differential protection of distribution networks or application scenarios without GPS or situations when time synchronization is interrupted.