Innovative 12kW Three-level Power Supply for AI Servers Empowered by 400 V SiC MOSFET Technology

Abstract:
This paper presents a 12kW AC/DC single-phase power supply to meet the growing power demands of data centers driven by training very large AI models. The combination of novel 400V SiC MOSFET device technology and multi-level topology are essential in achieving the desired power density (100 W/in³) and efficiency target (h > 97.5%). The introduction of 400V SiC MOSFET technology bridges the gap between 200 and 600V super-junction MOSFETs and is characterized by low switching losses and low on-state resistance. In order to keep the load transients of AI chips away from the AC line, a novel control concept involving a power-pulsation buffer circuit is introduced, which acts as an active filter and also provides full control of re-rush currents after line-cycle drop-outs.