Voltage Selection and Personal Safety in Low Voltage Direct Current Networks at Customer End

Low voltage direct current (LVDC) technology is becoming an attractive solution for the integration of renewable energies and the power supply of electronic loads. Since LVDC systems at the customer end are exposed to the daily contact of untrained users, they should be properly configured to guarantee the personal safety even under fault conditions. This paper derives guidelines for the selection of suitable voltage levels and the minimum requirements for protective devices from the perspective of personal safety in LVDC customer-end networks. For this purpose, a comprehensive analysis of the underlying influencing factors is presented, followed by a thorough discussion of the state-of-the-art in LVDC fault protection.