Research On Key Technologies Of Magnetic Coupling Wireless Power Transmission System

With the rapid development of mobile devices such as electric vehicles,drones,medical implantable chips,and underwater unmanned underwater vehicles.The research and development of wireless power transmission theory and related equipment has become a research hotspot.According to different transmission principles,wireless power transmission can be divided into magnetic induction type,laser type,microwave type and magnetic coupling type.Among them,magnetic coupling resonant wireless power transmission is favored by many researchers because of its moderate transmission distance and moderate transmission efficiency.However,how to maintain high-efficiency charging when the axial distance or radial offset of the receiving coil changes is the main problem faced by magnetically coupled resonant wireless power.In addition,the energy of the DC power supply of the wireless power transmission system is limited.In extreme environments such as islands and plateaus,the energy supply station is far from the rear base,and the supply guarantee is difficult.How to ensure the uninterrupted power supply of the DC power supply of the wireless power transmission system is also the key to research.question.Aiming at the above problems,this paper carried out the research on the anti-offset optimization design of the magnetic coupling wireless power transmission system,and designed a new wireless charging system based on photovoltaic power generation and wind power generation.The main work and innovations of this paper are as follows:First,the effect of coil offset on the mutual inductance of the coil and the efficiency of the wireless power transfer system is studied.The experimental results show that the transmission efficiency and mutual inductance value of the system decrease with the increase of the axial distance and radial offset of the coil.In the same case,the axial distance has a greater impact on the mutual inductance value and the transmission efficiency of the system than the radial offset.With the increase of the axial distance,the influence of the increase of the radial offset on the mutual inductance becomes smaller.When the axial distance increases,with the increase of the radial offset,the transmission efficiency of the wireless power transfer system decreases at a larger rate.Secondly,an anti-offset optimization method based on the combination of the switching transmitter coil method and the impedance matching method is proposed.The experimental results show that when the position of the receiving coil changes,switching the transmitting coils with different inner diameters can improve the efficiency between the coils.After the impedance matching circuit is embedded,the efficiency of the wireless power transfer system is further improved and the maximum power transfer can be maintained.Finally,a wireless charging system based on wind and solar energy storage is proposed.The simulation results show that the system can achieve the maximum power output regardless of whether the photovoltaic cell or the wind power generation system is powered alone or both are powered together.