400VDC distribution architectures for central offices and data centers

400VDC distribution enables a variety of different power architectures that closely match three main attributes driving new power technologies today: availability, efficiency and scalability. The presented 400VDC distribution architectures offer the simplicity of -48VDC power infrastructure and the benefits of higher distribution voltage already in use in AC power infrastructure. It makes 400VDC a compelling alternative to other power architectures for central offices and data centers. However, unfamiliarity with 400VDC technology and limited availability of 400VDC ICT equipment are hurdles for mass deployment today. The objective of this paper is to give an overview of the selected 400VDC architectures which are alternatives to the existing AC power architectures in data centers and -48VDC architectures in central offices. Another subject for this paper is to show the benefits and the drawbacks of 400VDC architecture vs. AC and -48VDC power infrastructures. Finally, the application of two grounding concepts, IT and TN-S, in 400VDC is discussed and compared to TN-S that normally is applied in AC and -48VDC architectures.