Class-E self-oscillation for the transmission of wireless power to implants

This paper develops the concept of Class-E self oscillation for wireless power delivery to implantable sensors with the comparison of several topologies. Power amplifiers and oscillators are considered as two separate blocks in wireless power transmission. By combining these topologies into a self-oscillating power transmitter, greater efficiency can be achieved. Various topologies are compared with measured hardware results, determining that a crystal feedback network provides both accuracy and high power output. A new crystal feedback Class-E self oscillator has been implemented by transmitting power through 2 cm-thick biological tissue. The paper includes a second order modelling and design process that can be used to design a Class-E self oscillator as an inductive power transmitter as well as measured results. (C) 2011 Elsevier B.V. All rights reserved.