This work demonstrates a three-phase motor drive Integrated Power Module (IPM) based on Gallium-Nitride (GaN) power transistors for major increase in efficiency and power density compared to industries best in class. Thanks to the superior characteristics of GaN and intelligent gate driver design, this work reduces losses achieving efficiency up to 99.1%. The high efficiency enables 250W power delivery without heat sink in a 65% smaller package (12mm*12mm QFN) compared to state-of-the-art silicon-based implementations. High integration is required for intelligent gate driving achieving high efficiency and power density while keeping the GaN transistors protected. This design integrates adaptive dead-time control based on in-situ power stage sensing to minimize third-quadrant conduction loss and THD. Challenges such as slew-rate control despite the highly non-linear capacitances in GaN are addressed by package-integrated gate drivers.Technology basics are provided to understand the challenges of using GaN for motor drives. Measurements of this work and existing silicon-based IPMs are shown to quantify the benefit in terms of efficiency, power density and THD enabled by GaN.
