Multi-hop Routing Optimization of Transmission-Line Monitoring Based on the LoRa Technology

As the power transmission network connects the power generation side and power consumption side, the transmission line plays a vital role in the overall stable operation of the power grid. However, because power transmission lines are often distributed in a very harsh environment, they are extremely susceptible to being interfered with by dynamic scenarios and face transmission failures. Therefore, to maintain the power transmission, it is urgent to monitor the status of transmission lines in real time. Traditional communication technologies, such as GPRS, optical fiber, ZigBee, etc. are widely used in power monitoring systems, but their limitations make it difficult to meet the remote monitoring of transmission lines. The long-range (LoRa) technology has the characteristics of wide coverage and low energy consumption, providing an opportunity to make up for the “last-mile” gap in transmission-line monitoring. The challenges to monitoring the transmission lines are: 1) the nodes far away from the base station need to transmit the data with considerable transmission power; 2) the nodes outside the communication range of the base station cannot successfully send the data to the base station. To address these problems, this paper proposed a multi-hop communication strategy to monitor the status of transmission lines. First, we use a graph to represent the LoRa nodes and transfer the 3-phase line monitoring structure to the 1-phase line monitoring. Second, we construct an energy consumption model for each LoRa node in the multi-hop scenario. Third, we develop a max-min optimization problem to compute a multi-hop scheme for minimizing the overall energy consumption for the transmission-line monitoring and maximizing the transmission range for the base station. Finally, we conduct extensive simulations to analyze the bottleneck of the energy consumption of the overall monitoring system with LoRa and the maximum range that the base station can cover.