Control System Design Challenges in Renewable Energy-based Offshore DC Microgrids

Since the majority of modern electronic devices rectify an AC input to operate via DC power, and since many distributed renewable energy sources (DRESs) inherently generate DC power, DC microgrids (MGs) are an increasingly attracting approach. DC MGs can provide a sustainable alternative for offshore facilities such as oil and gas rigs, marine shipboards, and aquaculture facilities, offering a sustainable and efficient substitute to conventional power systems. This is because these industries have access to different DRESs, especially ocean wave energy, and often utilise DC-powered modern electronic devices. When integrating different DRESs into a DC MG network for powering offshore industries, a robust control system is essential for maintaining system stability under all feasible operating conditions. This paper reviews the control system design challenges for offshore DC MGs, considering variations in generation output and in load characteristics. This review summarises the current state and technical challenges of control system design for offshore DC MGs and provides perspectives on how to address these challenges.