Design of wireless charging system for 25 horsepower electric tractors based on magnetic coupling resonant

摘要

As a green agricultural machinery, electric tractor will be widely promoted and applied. Wired charging is prone to cause poor contact and leakage during plug charging process, which brings potential safety hazard. Wireless charging can avoid above problems. In this paper, an intelligent and efficient wireless charging system for 25 horsepower electric tractors is designed, including wireless power transfer device and intelligent monitoring system. This paper introduces the design methods and steps of each link of wireless power transfer device, which is mainly based on the principle of resonant coupling. The energy is coupled to wireless power receiving coil by wireless power transmitting coil. Experimental results show that efficiency of wireless power transmission is over 85% and transmission power reaches 30kW when two coupling coils are in 19 ± 4 cm range in vertical direction and different migration states(offset 10cm and 5cm in single direction respectively, and offset 10cm and 7.5cm in both directions at the same time) in horizontal direction. Transmission power can meet the rapid charging demand for 25 horsepower electric tractors.