GaN-Based Oscillators for Wireless Power Transfer Applications

This paper reports linear- and switching-mode oscillators based on GaN power device that can be used efficiently for wireless power transfer (WPT) applications. The proposed oscillators are designed using a packaged GaN high electron mobility transistor (HEMT) from Transphorm Inc. In the first design a class-AB has been adopted and implemented to provide lower harmonics oscillator that can be used for electromagnetic interference (EMI) sensitive WPT applications. In the second part, higher efficiency class-E oscillator based on the same transistor has been designed and implemented to provide an optimal solution for higher power WPT applications. Both oscillators have been implemented and tested. The oscillators produce high output voltage up 40 V with lower total harmonic distortion of around 10% for class-AB and higher efficiency of around 90% for class-E oscillator.