Distributed Cooperative Wireless Charging for the Mine Internet of Things

Existing wireless charging methods for one-dimensional space are not suitable for coal mine roadways due to the crowding problem of mobile chargers (MCs). To solve this problem, we propose a novel method called distributed cooperative wireless charging, in which a coal mine roadway segment is divided into sections, and each MC is responsible for charging the nodes in its own section. From time t = (K - 1/2)T, all the MCs of a segment start to work simultaneously, where K is the number of sections and T is the charging cycle. When the steady state is reached, distributed cooperative wireless charging is the fastest method to finish a round of charging. To guarantee the practicality of the algorithm, we also provide the method to determine the MC battery capacities and the roadway section lengths. The numerical simulations indicate that the proposed algorithm provides better charging efficiency than the existing one-dimensional charging methods in coal mine roadways.