Izuru Narita

High-voltage DC-DC power module development

The world economy and future progress of civilization will require more electricity supply with higher efficiency and less environmental impact. Globally, of all electricity ever generated, around half has been consumed in the past 15 years. Clean energy alternatives such as solar power and wind power are being adopted at the central source to provide more energy generation. However the hidden challenge is in the transmission. High voltage direct current (HVDC) is a clear choice. Compared with traditional AC (alternating current) transmission, HVDC is smaller, cheaper and more efficient. For example, HVDC has 30-50% less transmission losses, and require less material/cables for line route. Also, DC distribution has a higher reliability compared to AC distribution as proven by 48V DC. For IT equipment designed to use an AC distribution, it requires an AC UPS with Battery back up to support system operation during brown out conditions. The telecommunication industry uses 48V DC input to power telecommunication equipment. It is a DC distribution system and uses battery backup system for supporting the system operation during brown out conditions. AC systems have a higher cost of AC UPS if used in modular form, lower efficiencies and reliability issues when compared to DC distribution. Therefore, DC distribution at 380V DC is being considered to power the datacenters of the future. Although telecommunication already uses DC distribution, the 48V DC bus voltage is not sufficient to deliver sufficient power with the existing distribution cables for the future telecommunication systems. Efficiency of distribution is very poor at 48V DC compared to 380V DC. iNEMI formed a project team in 2013 to develop technical specification for a High Voltage DC-DC module, and plans to build and test a prototype to verify the target electrical requirements against measured data. This HV (380V) DC-DC module will be the start of introduction of High Voltage technology on system boards which will provide a low cost power solution to the industry compared to the existing solutions which are bulky and more expensive. The overall cost of the power system in a Datacenter will be lower compared to the existing AC-DC systems. This paper will introduce the background and progress of the project, as well as challenges to adopt HVDC.