An Algorithm for Designing AC Generators for Inductive Powering Systems of Batteryless Implants

Abstract

An algorithm for designing AC generators based on class E amplifiers for inductive powering systems of batteryless implants was proposed. Parameters of three different inductive powering systems were calculated using the suggested algorithm. Each system used a pair of symmetric antennas with inductances of 3.4, 7.29, and 12.27 μH, respectively. The energy transfer efficiency and the output power of the inductive powering system based on class E amplifier were calculated as functions of the axial distance between the transmitter and the receiver for each of the three antenna pairs. The efficiencies of the systems built around antennas with inductances of 3.4 and 7.29 μH were found to be higher than 90% for axial distances in the range from 10 to 25 mm. It was found that the class E amplifier should be tuned at the minimum rather than the medium distance between the antennas.