Fault Analysis of LVDC Grid on the Hydrogen Research Platform WAVE-H2

Abstract:
This publication focuses on modelling and simulating the low-voltage direct current (LVDC) grid within the hydrogen research platform WAVE-H2 in Freudenstadt, Germany. The platform facilitates the integration of sector coupling systems and enables the evaluation of flexible energy utilization strategies. It provides the necessary infrastructure for assessing various operational scenarios and system configurations, accommodating electrical power distribution in alternating current (AC) and DC, and utilizing hydrogen, natural gas, and thermal energy. During the design process of the LVDC grid, it is essential to analyze short circuits and ground faults to select suitable protection devices and ensure operational selectivity. Currently, no practical calculation methods are available for fault analysis in DC. Therefore, the LVDC grid and its connected devices and systems for initial commissioning are modeled and simulated using Modelica. Different modelling approaches for the active infeed converter were investigated, and their effects on the accuracy of simulation results and computing time are benchmarked in this work.