Research on Dynamic Wireless Power Transfer Technology for Maximum Equivalent Energy Transmission of Embedded Sensors

To address the issue of long-term reliable power supply for embedded sensors in subgrade along the rail transportation system, this paper proposes a method utilizing a detection vehicle to provide power to the subgrade sensors through bottom-mounted transmitting coils. Furthermore, an optimization approach for the DD transmitting coils is presented, with the constraint of the detection vehicle clearance as the limiting factor, aiming to maximize the output power of the dynamic wireless power transfer system. By comprehensively considering the variables associated with DD coils along with the clearance height, a comprehensive equivalent circuit model incorporating the reinforcing bars is constructed. Through magnetic field calculations of the hollow coils and analysis of the impact of various parameters on the system’s output power, corresponding conclusions are derived and elaborated upon regarding how to leverage these findings to enhance the output power. Finally, the validity of the proposed method is validated through theoretical calculations. The dimensions of the transmitting coil are 150 mm × 150 mm, with the auxiliary coil closely wound around a 12 mm diameter rebar. When the height is set at 150 mm, and an example speed of 7 m/s is considered, the optimized coil parameters result in a 50% increase in output power, achieving 0.14 W·s, thereby meeting the power supply requirements of multiple sensors.