System Integration of a High Efficiency HDD Storage Server with Series-Stacked Voltage Domains and Differential Power Processing

Abstract

As the global requirement for data processing and storage increases, data centers will need to become more energy-efficient to avoid exponential growth in energy and cost. One method of achieving this is to reduce losses by utilizing a series-stacked server architecture. The energy processing unit (EPU) designed by Princeton Power Electronics Research Lab (PPERL) allows regulated power delivery across series-stacked voltage domains through a multiport ac-coupled differential power processor (MAC-DPP). Communication between hard disk drives (HDDs) across series-stacked voltage domains can be achieved using the standard SATA interface when the ground wires are cut. Data transfer speeds were measured in a 20 HDD experiment. Communication was found to be faster when read/write tasks were: 1) distributed amongst multiple backplanes to avoid data transfer bottlenecks; 2) held across smaller voltage gaps.