Analysis Based On Magnetic Coupling Resonant Cascade System

Since 2007, the scientists at the Massachusetts Institute of Technology,Marin Soljacic et al use magnetic coupling resonance principle successfully light a bulb with 2 meters distance and 60 w power, the use of magnetic resonance coupling of distance wireless power transmission technology has gained great attention.Magnetic coupled resonant wireless power transmission refers to the receiving coil and the transmitting coil, with the same resonant frequency, has the strong electromagnetic coupling in the magnetic resonance effect, so as to achieve a near zone energy efficient transmission. Compared with other wireless power transmission technology, magnetic coupled resonant wireless power transmission technology has these characteristics, simple device, small electromagnetic radiation and no harm to human body. It is suitable for medium distance wireless transmission. This can solve the problem of indoor power supply well, which are closely related to life. But at present the technology is still in the initial stage, and can not achieve the transmission distance and high efficiency.In the paper, the three aspects of theory, experiment and simulation are carried out to study the mechanism of magnetic coupling resonance radio transmission, in order to improve the transmission efficiency and increase the transmission distance. Multistage coil device are used to realize resonance interaction of plurality of coaxial coil, so as to optimize the performance of the magnetic resonance wireless power transmission system. The thesis is studied from the following directions:(1) Firstly, the magnetic coupling resonant system is based on the coupled-mode theory. Then set up the resonance coupling circuit theory model of secondary and tertiary series. Finally, The formulas are derived to calculate the transmission efficiency parameter of wireless power transmission system.The research provides the actual way of thinking for the optimal design of the transmission system.(2) A theoretical model simulation using the software of Matlab programming is established to analysis the relationship between the transfer efficiency, the transmission distance, axis offset and the relay coil. Through the above research we can optimized design the best magnetic coupling radio transmission system.(3) The paper successfully build a spiral coil and a square coil magnetically coupled radio transmission platform, and test the mock-ups using vector Network Analyzer. The experimental results show that the change of sensing distance, transmission distance, and the deviation of the center axis have aneffect on the transmission efficiency of the system. The performance of the multistage cascade loop resonance model is directly measured, which can prove that the system is able to extend the transmission distance and improve the transmission efficiency. This provides a way to solve the problem of wireless power transmission in the distance.(4) For the first time, the paper apply electromagnetic simulation software HFSS in the magnetic coupling resonant wireless power transmission, and successfully established simulation model. The simulation result shows that the curve of the S parameter graph reflects the trends of energy transfer efficiency.Comparing the simulation analysis with experimental results, we found that the two have good consistency. The experimental results can be replaced by simulation results directly, in the later study, which provides convenience for the design and optimization of wireless power transfer system.