High-efficiency LC-S compensated wireless power transfer charging converter for implantable pacemakers

Abstract

This paper deals with wireless power transfer (WPT) based on magnetic coupling resonance in order to delivery power to a cardiac pacemaker from the outside of the body. The high-efficiency power delivery, implantation, and safety are key parameters for a WPT system, designed for active implantable medical devices. Therefore, this paper is focused on high-efficiency power transfer, implantation, and safety issues. For the wireless charging of the pacemaker, the LC-S compensation topology is presented and designed based on high-efficiency power delivery. The resonant components of the LC-S compensation topology were extracted in order to ensure that WPT converter operates at resonance frequency. The operation of the presented WPT charging converter is validated by a prototype operating at 300-kHz operation frequency. At 4.2 V output voltage and 0.45 A output current, the WPT efficiency of the prototype is measured as 82.39%. Finally, the safety evaluation of the proposed WPT converter is also discussed based on reference values presented in the literature.