Stability Assessment of Renewable Energy-Based DC Microgrids for Offshore Applications

Traditional offshore microgrids such as drilling rigs and oil and gas platforms rely on diesel generators to provide their electricity needs. With the recent developments in offshore wind, solar and wave generation, and the maturity growth of the energy storage technology, the offshore microgrids are transitioning away from diesel generation. When the majority of the energy sources and loads is DC-native or rely on conversion to DC, setting up the network as a DC microgrid becomes a viable option. Using DC coupling in offshore microgrids eliminates the problems of harmonic distortion, low inertia and overcomplicated control. However, with the high penetration of intermittent generation, the provision of DC microgrid stability becomes a challenging task. This is particularly acute within practical DC microgrids since, at this stage, there are not many off-the-shelf DC components. This paper describes the experimental lab facilities set up for offshore DC microgrid research and investigates the stability issues presented in the renewable energy-based DC microgrid.