A Review of Power Distribution Architecture Solutions for Servers within Data Centers

Date: 10/12/2026
Time: 9:00 am
Presenter: Dorin Neacsu
Abstract: (This webinar is sponsored by PELS TC 7) Servers and data centers continue to grow the demand for higher efficiency and higher power density. This lecture focuses on defining their power distribution systems in respect to standards, regulation, big-corporation plans, and power system realities. First, definitions for general servers, rack servers, and blade servers are provided. Requirements for reliability, availability, and installed power are explained using Uptime Institute’s and TI’s classifications. A decision between low-voltage and medium-voltage supply is herein recommended based on power level by means of regulation for installed power as defined within various countries. Solutions towards intermediary bus of either 48/54 V or 12 V are discussed for both AC and HVDC supply. The “80 Plus” efficiency standards used by industry are included for qualification of the AC-to-12 V conversion units (a.k.a. PSU). Solutions for 48/54 V or 400/800 V DC distribution bus inside the cabinet are explained, as the Open Compute Project is currently standardizing 800 V. A variant based on a series connection of servers is discussed. The lecture continues with various on-the-board circuits for power conversion from intermediary DC bus towards a low-volt-range digital load – the voltage regulators (VR) or point-of-load (PoL) converters, in either lateral, vertical, or on-chip location. Circuits are classified and compared for their benchmark efficiency and power density performance, represented with either contemporary industrial products or research results. The improvements with GaN transistors and serial communication (PMBus) are demonstrated. The lecture is rich in examples and represents a great introduction to the amazing opportunity for grid-to-chip funded research.
Dorin O. Neacșu (IEEE M’95-SM’00) has received the MSc and PhD degrees in Electronics from the Technical University of Iasi, Iasi, Romania, in 1988 and 1994, respectively, and a MSc degree in Engineering Management from Gordon Institute for Leadership, Tufts University, in 2005. Dorin has been involved with TAGCM-SUT Iasi, Romania, from 1988 to 1990, and with the faculty at Department of Electronics, Technical University of Iasi, Romania, between 1990 and 1999. Following 1999, he was involved with the U.S. industry as an engineer, consultant, product manager, and project manager, and with U.S. academic activities. Since 2012, Dorin is an Associate Professor with Technical University of Iasi and was a multi-year Visiting Associate Professor with Northeastern University, Boston, MA, USA. Professor Dorin O. Neacșu has organized 14 professional education seminars (tutorials) at IEEE conferences, has been awarded 4 US patents, and has provided a continuous stream of IEEE paper publications since 1992. He has published “Switching Power Converters – Medium and High Power” (Third Edition, August 2025), “Telecom Power Systems”, “Automotive Power Systems”, all books available at CRC Press/Taylor and Francis. He has received the 2015 “Constantin Budeanu” award of the Romanian Academy of Sciences, the 2018 “Ad Astra” award from Romanian Researchers Association, and the 2026 “TPEL Associate Editor Excellence Award”. Dorin is the Chair of the TC7 “Critical Power” Technical Committee of IEEE PELS for 2024-2025 and 2026-2027, an Associate Editor of IEEE Transactions on Power Electronics, an Associate Editor of IEEE IES Magazine, Reviewer for IEEE Transactions and Conferences, and served as Track or Technical Committee Co-Chair for several conferences (INTELEC, APEC, ECCE, OPTIM, ISIE).