Research On Efficient Underwater Magnetic Resonance Coupling Wireless Power Transfer

For a long time,providing a simple,safe and efficient energy supply for underwater equipment has been a major concern in deep-sea engineering.The traditional cable charging method has the problems of complex docking mechanism,poor security and high cost,etc.The technology of wireless power transfer can effectively make up for the shortcomings.Among them,the Magnetic Resonance Coupling Wireless Power Transfer(MRC-WPT)technology is the most suitable power transfer mode for underwater environment.Because of its high transmission efficiency,appropriate transmission distance.However,the underwater MRC-WPT technology also has the problems of low transmission level due to eddy current loss,poor stability due to seawater disturbance,and electromagnetic interference in application.Therefore,this dissertation analyzes the equivalent circuit of MRC-WPT and the magnetic field distribution of the coil.And it studies the characteristics of the underwater MRC-WPT technology.In view of the existing problems and challenges,the improvement and solution are proposed in this dissertation.Two kinds of wireless power transfer schemes are proposed according to the requirements of underwater location.Due to the transmission characteristics of the parallel coupled resonant circuit are better than the series one.In this dissertation,we choose the parallel resonant circuit to study its equivalent model,and design the mode based on it.We put forward two kinds of wireless power transfer schemes.It changes the positioning mode of the two-dimensional transmitter coil,and the structure of the three-dimensional transmitter coil.According to the two design schemes,the simulations and application structures are designed respectively.The results show that these schemes reduce the effect of position shift.And it improves the power transfer level.In application,the traditional underwater MRC-WPT technology is easy to interfere with other equipment.We propose a wireless power transfer method of four-phase magnetic core coil.By studying the magnetic field distribution of the transmitting coil,we add a magnetic core and air gap to the transmitting co il.What's more,we study the distribution of its near-field magnetic field,and the influence of magnetic core and air gap on the magnetic field.Based on this,we propose a wireless power transfer scheme of four-phase magnetic coil.Based on the analysis of underwater application scenarios,two applied models with high universality are proposed.Simulation result shows that the scheme presented in this dissertation has the ability to avoid interference with other devices.