GaN oscillator-based DC-AC converter for wireless power transfer applications

Abstract

This chapter reports a design for linear and nonlinear switching-mode oscillator based on GaN high electron mobility transistors (HEMTs) for wireless power transfer (WPT) applications. The linear oscillator is based on a lower power depletion-type GaN-HEMT, while the nonlinear oscillator is implemented using a higher power enhancement-type GaN transistor. In-house advanced design system (ADS)-based model has been used for designing the lower power oscillator, while a commercial LTSpice model has been implemented for designing the higher power oscillator. The oscillators are designed and simulated using computer-aided software (CAD) and then realized and tested with transmitting and receiving coils. The realized linear-mode oscillators show good efficiency of dc-to-ac conversion (up to 45%) with lower total harmonic distortion (THD) in the order of 10%. This makes those oscillators proper for electromagnetic interference (EMI) sensitive applications. On the other side, the switching-mode oscillators provide higher efficiency up to 90%, which is optimal for designing high power WPT systems.