Comparative evaluation of GaN transistors and Si MOSFETs for use in inductive power transfer systems of biomedical implantable devices

摘要

In this work, comparative evaluation of Si MOSFETs and GaN transistors is performed for utilization in the H-bridge Voltage Source Inverter of Inductive Power Transfer Systems, developed for biomedical applications. The evaluation is made on a 10W prototype wireless charger. Simulations and experiments are carried out within two different ranges of frequencies, for a wider investigation and a more complete assessment. The efficiency results show similar performance for the two types of devices for the lower range of frequencies, whereas the superiority of GaN transistors is evident in the higher range. Ultimately, the choice of the type of semiconductor is related to the requirements of the application and the control scheme and cost are key factors that have to be taken into consideration.