Review of Non-Isolated DC/DC Converters for Application in Data Center Power Delivery

Data centers present an interesting case of power delivery architecture, drawing power from medium voltage lines to power innumerable low-voltage point-to-load (PoL) converters. Towards the load end, the incoming distribution voltage (either AC or DC) is stepped down using back-to-back DC/DC converters. These converters are designed to efficiently operate at high attenuation factors and high currents, as the losses dictate the complexity of the cooling system and subsequent water consumption. With the emerging wide-bandgap semiconductors and high-frequency magnetic components, many recent converter topologies are worthy of replacing the conventional power converters (both regulated and unregulated) employed in data centers. This paper explores the power delivery architecture in data centers and assesses the performance requirement of non-isolated DC/DC converters. Based on these inputs, the recent non-isolated power topologies suitable for 48V-12V and 48V/12VPoint of Load (PoL) converters are reviewed and evaluated based on different criteria. Potential opportunities for improving the sustainability and efficiency of the power delivery architecture of data centers are also presented.