Minimum Power Input Control for Class-E Amplifier Using Depletion-Mode Gallium Nitride High Electron Mobility Transistor

• Main Authors: You-Chen Weng, Chih-Chiang Wu, Edward Yi Chang, Wei-Hua Chieng
• Format: Article
• Language: English
• Published: MDPI AG 2021-04-01
• Series: Energies
• Subjects: wireless power transfer; class-E amplifier; minimum power input control; D-mode; GaN HEMT; gate drive
• Online Access: https://www.mdpi.com/1996-1073/14/8/2302

In this study, we implemented a depletion (D)-mode gallium nitride high electron mobility transistor (GaN HEMT, which has the advantage of having no body diode) in a class-E amplifier. Instead of applying a zero voltage switching control, which requires high frequency sampling at a high voltage (>600 V), we developed an innovative control method called the minimum power input control. The output of this minimum power input control can be presented in simple empirical equations allowing the optimal power transfer efficiency for 6.78 MHz resonant wireless power transfer (WPT). In order to reduce the switching loss, a gate drive design for the D-mode GaN HEMT, which is highly influential for the reliability of the resonant WPT, was also produced and described here for circuit designers.