Defense: Ram Rakhyani
April 21, 2014
UNIVERSITY OF UTAH
ELECTRICAL AND COMPUTER ENGINEERING DEPARTMENT
DISSERTATION DEFENSE FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY
Anil Kumar Ram Rakhyani
Advisor: Gianluca Lazzi
Design and Optimization of Efficient Magnetic Coils for Biomedical Applications
Magnetic fields are permeable to the biological tissues and can induce electric field in the conductive structures. Prosthetic devices such as retinal implants use time-varying magnetic field to achieve wireless power transfer to the implanted magnetic coil. However, devices such as magnetic stimulators use the induction principle to create an electric field at the stimulation site. Efficiency of these devices is primarily dependent on the design of the magnetic coils. Therefore, in this work, we designed and validated efficient magnetic coils for wireless power transfer to implanted devices and magnetic stimulation of the peripheral nerves.
In this work, we proposed a multi-coil power transfer system which solves some of the current challenges. The proposed multi-coil WPT system achieves more than twice the power transfer efficiency, controllable voltage gain, wider frequency bandwidth, higher tolerance to coupling and load variations, lower absorbed power in the tissue and lower radiated field from the magnetic coil than a comparable conventional system.
Magnetic coils play an important role in controlling the distribution of induced electric field inside the nerve during magnetic stimulation. In this work, we developed anatomically correct tissue models to study the effect of tissue heterogeneity and the surrounding media on the induced electric field. We also developed an optimization algorithm for designing energy efficient cm-size magnetic coils, that were then used for ex-vivo magnetic stimulation of the frog’s sciatic nerve.
Thursday, April 24, 2014
ECE Conference Room
The public is invited