The Analysis Of Output Property And Optimization Of Magnetically-coupled Resonant Wireless Power Transfer System

Humankind never stop researching on power transfer for higher efficiency and more flexibility since 19 th century. However, along with the high speed development of science and technology today, electric devices are nearly everywhere, and thus, in some special circumstance, traditional power transmission method, like power cables and wires, are no longer suit. As a result many researchers change their focus to wireless power transfer in recent years.Magnetic-coupled resonant wireless power transfer system as an applicable wireless power transfer system for mid-range, since it was experimented and reported by MIT team, becomes one of the most popular system of wireless power transfer. However, it's efficiency and output power always bothers researchers and, undoubtedly, serve as a bottleneck for further development. In order to analyzes and optimize output power of magnetically-coupled resonant wireless power transfer system, this paper mainly dealt with the output property of this system in both theoretical and practical way, and gives a simplified model of this system which can help designer analyzes or determine the parameters of the magnetically-coupled resonant wireless power transfer system. Moreover, in magnetically-coupled resonant wireless power transfer system, the output power can vary drastically with the change of relative distance and position of those two resonant coils. Based on the output property discussed above, to solve the problem, this paper proposed a practical MPPT method to stabilize and maximize the output power of the system in relatively wide range. The final purpose of this method is to maximize the power and stabilize the output of current magnetic-coupled resonant wireless power transfer system. Moreover, this paper designed a relatively high power wireless transfer system based on the method, which discussed in this paper, and theory mentioned above. The experiment shows that this system can transfer up to 80 watt power more stable than traditional system.In the later part, based on this method and the system this paper designed a railway wireless power transfer system which can transfer power to moving object, experiment shows that this system is stable and efficient, as a result prove this kind of railway wireless power transfer system has broad research prospects and great research value.