Optimisation design of real-time wireless power supply system overhead high-voltage power line

Efficient and reliable power supply has been considered as the fundamentality of applying monitoring equipment overhead high-voltage power line (HVPL). Several kinds of energy harvesting devices are investigated and compared. A new power supply scheme, which integrates the online energy harvesting device and the wireless power transfer (WPT) system, is presented. Optimisation design of online energy harvesting device is analysed emphatically by taking both HVPL insulation distance and wireless power supply efficiency into account. For further increasing the harvested energy from power lines, this study discusses the design of specific device structure and the accurate calculation of maximum output power. It is found that essential parameters and exciting current angle contribute to more extracting energy. Meanwhile, in order to expand the transmitting distance with high efficiency, the WPT system with double relay coils is selected. The charging threshold voltage of the load can be further optimised under different transmitting distances by adopting an AC-DC voltage-doubling rectifier circuit. Simulation and experimental studies show that when the transmitting distance is >1m, the monitoring equipment can also be charged in a reliable way, which also verifies the correctness and feasibility of the system.