Efficient Wireless Power Transfer For Low Power Wide Area Networks

Abstract

Wireless power transfer (WPT) technologies for small devices and low power sensors have drawn substantial research attention in recent years. Traditional near and far- eld WPT systems cannot provide e cient-high power transfer while at the same time maintaining long range power transfer. A possible candidate to overcome these challenges is the strongly coupled magnetic resonance (SCMR) WPT technique which can transfer power at higher transmission e ciency in the medium range. Heretofore, the focus has been to improve the e ciency and range of the SCMR system. On the other hand, the study to develop optimal coils or loops of the WPT system utilising less computational resources as well as using co-simulations between less and high intense software has been limited. More so, the existing WPT systems are complex and bulky in size making it a challenge to use these technologies for small footprint applications. Therefore, innovative SCMR systems that are designed to be easy to fabricate and with low losses and of small footprint will notably improve various technologies in a variety of applications. The optimal and small footprint SCMR WPT systems are studied in this work. The analytical models of the Conformal-SCMR (CSCMR) system are presented rst through design methodology and analysis. The designed CSCMR systems' performance is envisaged from the identi ed optimal design parameters through this analysis. Furthermore, the derived optimal parameters are fabricated, analysed and compared in a 3D simulator, a conventional CSCMR model and a 2-layer self-resonant resonator model. It was noted that the 2-layer self-resonant model performed better than the conventional model and this was veri ed by mathematical formulae and equivalent circuit models. The two models were then optimised using their derived physical parameters. This was done through a co-simulation. The results showed that the co-simulation increased the simulation speeds, therefore saving computational resources. In conclusion, the two optimised model's transmission e ciency was improved by 30% and 4% for the conventional derived and the 2-layer self-resonant CSCMR-WPT systems. This was achieved while the footprint of these systems was reduced.