| With the development of computer,microelectronics and communication technology,wearable technology becomes a top research field,and receives wide attention of researchers.But in the development process of wearable technology,many problems have not been solved,especially the short duration of the battery and the charging difficulties.It seriously affect the development of wearable devices.The wireless energy transmission technology provides a new way to solve this problem,and the analysis of tiny wireless energy transmission system based on wearable devices has important academic value and application value.Magnetic coupling resonant wireless energy transmission technology has the advantages of long transmission distance and high transmission efficiency,and it is convenient and safe.In this paper,the tiny wireless energy transmission system has been analyzed.In order to improve the energy transmission efficiency,the parameters of the system have been analyzed,and the wireless energy transmission system has been built,and the biological safety of the system has been evaluated.These works lay a foundation for the application of wireless energy transmission technology in the field of wearable devices.Main research work in this paper are as follows:1.The energy transmission system parameters are optimized.The coupled mode theory and mutual inductance coupling theory are used to analysis the transmission mechanism and transmission condition of magnetic coupling resonant wireless energy transmission system.The design parameters of the magnetic coupling resonant wireless power transmission system are changed to analysis the influence on transmission efficiency,and the optimal parameters are selected.2.The tiny magnetic coupling resonator is designed.The planar spiral resonator simulation model is established.The influence of parameters on the resonance frequency is determined by changing the design parameters,and the key parameters that seriously affect the resonance frequency are obtained.Based on the simulation,the tiny magnetic coupling resonator is designed with the volume of 0.675 cm3.3.The wireless energy transmission systems are built.Two magnetic coupling resonant wireless power transmission systems have been built.One with the same resonators,the other with a big size resonator and a small size resonator.The experiments of the two systems have been done on different condition,and the transmission performance of the two energy transmission system are analyzed.4.The biological safety of the system is analyzed.The human head model with four layers is established,and the distribution of SAR in the human head is simulated,when the magnetic coupling resonant wireless power transmission system provide energy for wearable devices.The results show that the system is safe to human. |
