An Improved Hybrid Time Synchronization Approach in Wireless Sensor Networks for Smart Grid Application

Wireless sensor networks (WSNs) powered by energy harvesting is a promising technology for monitoring and diagnostic systems in smart grid. However, the limitation and instability of harvesting energy leads to the requirement of high energy-efficient time synchronization algorithms for WSNs. In this paper, in order to minimize the energy consumption, we propose an improved hybrid time synchronization approach based on the combination of RBS (Reference Broadcasting Synchronization) and modified TPSN (Timing-Sync protocol for Sensor Network). According to the number of children nodes connected to a transmitter, a switch strategy is proposed by the hybrid method to calculate the optimal value that decides which time synchronization algorithm performs better in saving energy and choose the better one. Simulation results demonstrate that the hybrid method reduces the energy consumption significantly with an acceptable loss of synchronization precision by taking advantages of RBS and TPSN.