Wireless power transfer system using Helmholtz coils for powering Gastrointestinal Capsule biomedical implants

Abstract

The rapid development of portable and implantable electronic devices has prompted extensive research into wireless power transfer (WPT) methods. Existing commercial WPT techniques, which rely on coil coupling, face limitations including range, frequency constraints, safety issues, line of sight requirements, orientation sensitivity, and potential for interference. In response to these challenges, this paper introduces a novel WPT system utilizing two parallel opposed Helmholtz coils specifically designed for powering Gastrointestinal Capsule biomedical im-plants. Through in vitro simulations using the finite element model, it has been demonstrated that this system can achieve a wireless power transfer efficiency of 70% over a distance of 100 cm at a frequency of 218 kHz. Furthermore, experimental results indicate that the optimal power transfer efficiency is achieved with a coil's internal radius of 5mm. These findings highlight the potential of this innovative WPT system for powering biomedical implants, offering significant improvements over existing coil coupling methods.