A study on the protection scheme for LVDC distribution system in commercial buildings

This paper studies the protection scheme of a commercial building's low-voltage direct current (LVDC) distribution system. In the case of the AC power system, there was no difficulty in terms of protection system configuration and protection coordination because it had sufficient fault current supply capability. However, in the case of the LVDC system, the characteristics of DC fault current flow are entirely different from those of the AC system, and power converters could not continuously supply the fault current for more than tens of milliseconds. Therefore, it is very challenging to establish a protection scheme for an LVDC distribution system, such as commercial buildings with multiple-layer structures. This paper introduces the DC protection scheme applied to HD Hyundai Group's Global R&D center (GRC) in Pangyo, Seoul.