Design Of Wireless Power Supply System For UAV Based On Magnetic Coupling Resonant

With the wide application of UAV in environmental monitoring,power inspection,traffic control,express transportation and other fields,the power supply technology of UAV has received more and more attention.At present,the main use of lithium battery in the market is the main power,short of battery life is one of the important short board to limit the development of UAV.There are many problems such as mechanical wear,poor convenience and short circuit risk of dust,humidity and so on in the wired charging mode.Wireless power transmission technology can effectively overcome the problems of cable power supply,and has a wide range of applications in wireless sensor,electric vehicle,industrial robot and other industrial fields,which can provide ideas for the power supply of UAV.The magnetic coupling resonance transmission technology has important research value and practical significance with the characteristics of moderate transmission power,high efficiency and moderate distance.In this paper,the magnetic coupling resonant charging method is used,and the phase-locked loop control technology is used in the charging process,under the dynamic load changing conditions,the high frequency point of the output power and efficiency is automatically tracked to realize the fast and efficient charging of the UAV lithium battery.In this paper,firstly,the transmission mechanism of magnetic coupling resonance is studied.through the establishment of two coil and three coil circuit model,the transmission characteristics of two structures under constant frequency and fixed distance are compared and analyzed.Finally,the two coil structure is selected,on this basis,the influence of coil parameters,system frequency and load resistance on transmission characteristics is studied.Based on the research of transmission characteristics,the high frequency power supply is designed,which involves the design of high frequency signal generator and signal amplification factor,high frequency drive circuit,control circuit,protection circuit and power amplifier circuit.At the same time,considering the load,space and weight limitation of UAV,the structure of the resonator is designed to improve the transmission distance and efficiency of the system without increasing the area of the coil.From the single layer and multilayer of the planar spiral coil,the structure of the resonator is selected,designed and optimized.In the aspect of energy management,according to the load characteristics of UAV,through the detection of voltage and current of the receiving system,the optimal control strategy of wireless transmission can be designed.Finally,the hardware circuit is designed and the experimental platform is built.Based on the basic experiment,the working mode and resonator characteristics of the system are analyzed and optimized.On this basis,the hover experiment is carried out to study the changes of the transmission efficiency,receiving power and other characteristics of the UAV in the suspension and stop conditions.