Bidirectional Bipolar Electronic Overcurrent Safety Elements for Bipolar DC Grids

摘要

DC grids verifiably have the potential to be a strong partner of conventional AC grids, but safety elements for DC are few. Based on the analysis of different fault scenarios, the requirements for overcurrent safety elements for a bipolar DC microgrid in a TN and an IT structure are derived. First, a safety device for SELV DC buses is developed using JFETs as the main switches. Second, a self-powered, autonomous, and bidirectional approach for main buses is supplied by an energy-harvesting step-up converter and a micro-controller controls MOSFETs. Each section concludes with prototypes and their associated experimental results.