Design and Optimization of a High-Frequency GaN-Based ANPC Three-Level Converter as an Arbitrary PWL Voltage Generator

Recent advances in technology of GaN power devices and high-frequency magnetic materials are key enablers of small, compact designs of power converters in MHz range and the power range up to several hundreds of watts. However, impact of the devices and magnetic materials must be carefully characterized in order to fully understand the boundaries of current technology and to be able to exploit it fully. This is usually performed through a holistic, automated design procedure based on multi-objective optimization which focuses on the converter efficiency and power density for the given electrical parameters. In this paper, an optimized 100W, 1.75MHz-switching frequency, four-quadrant, voltage-source PWL arbitrary generator based on ANPC Three-Level converter is presented. The generator is capable of providing ±100V, ±1A at the output, with the tracking speeds up to 2V/µs, and the steady state efficiency beyond 95% and with a size below 12cm². Thermal management of the system is successfully resolved using advanced cooling plates based on pyrolytic graphite sheets and forced air convection. Having these characteristics, the presented generator outperforms existing linear and hybrid power amplifiers from the literature.