Wireless Electricity

Wireless Power Transmission Using Magnetic Resonance

Mandip Jung Sibakoti and Joey Hambleton Cornell College PHY312, December 2011, Professor Derin Sherman

1. INTRODUCTION Our project was based upon a MIT published paper in the year 2007 titled “Wireless Power Transfer via Strongly Coupled Magnetic Resonances” [1]. The project was researched by former Cornell students Lucas Jorgensen and Adam Culberson in the year 2008 [2]. During the course of this research, we investigated the need and usefulness of wireless power transmission and the feasibility of using magnetic inductive coupling as the means for wireless power transmission. The paper will outline our design process and the logical steps we took in the experimentation and design of our circuits. The first section of the document will explicitly illustrate the goals we set to accomplish during the allotted time frame of three and a half weeks. With the complexity of the problem in mind and what we must accomplish, our team began research on the available means to transmit power without a physical connection. 1.1 HISTORY Previous schemes for wireless power transmission included attempts by the late scientist Nikola Tesla and the Microwave power transmission. Both Tesla's design and the later microwave power were forms of radiative power transfer. Radiative transfer, used in wireless communication, is not particularly suitable for power transmission due to its low efficiency and radiative loss due to its omnidirectional nature. An alternative approach was pursued by a MIT team that exploited some near field interaction between the source and device so that efficient power transfer was possible. The approach was evanescent wave coupling. 1.2 THEORITICAL BACKGROUND The principle of Evanescent Wave Coupling extends the principle of Electromagnetic induction. Electromagnetic induction works on the principle of a primary coil generating a predominantly magnetic field and a secondary coil being within that field so...