Otimização de enlace indutivo ressonante com três bobinas para transmissão de energia sem fio

Abstract

Wireless power transfer through magnetic induction was first presented by Nikola Testla a century ago but, technical limitations did not let its immediate application at that time. It was only late of XX Century that commercial systems based on this technology could be offered. Nowadays this technology is considered the most appropriated to be used with portable devices like smartphones, tablets and so on. Additionally, it is the only technology available for dynamic charging of electric vehicles. In other words, charging while they are moving. In this kind of wireless power transfer technology, the energy transfer from the transmitter to the receiver is made through an electromagnetic link created by resonant coils. Several coils configurations can be used to implement the link. This work will focus on a system with three-coils assembled on axial alignment. The system performance will be evaluated in terms of power delivered to the load, efficiency and link distance. The three-coil system results will be compared with two-coil system results working under same operational conditions. That comparison points out the greater flexibility of three-coil system. This kind of system shows to be capable to function over a wider range of efficiency and power delivered to the load, which is not possible to the first one. Moreover, conditions under which the three-coil system shows to be more efficient, or able to deliver greater power to the load than two-coil system, will be discussed. Real data will be presented, as a case of a specific point of operation, in which the power delivered to the load is almost two times higher and efficiency is almost three times greater than the ones verified when using a two-coil system.