Stability and Feasibility-Driven Predictive Control for Next-Generation Naval Microgrids

Naval shipboard power systems are increasingly deploying direct current (dc) microgrids (MGs), hailed as the next-generation power solution. Nonetheless, dc naval shipboard MGs (DC-NSMGs) face significant challenges in maintaining stability and efficient power sharing, especially under critical military loads such as pulsed power loads (PPLs) and constant power loads (CPLs). Existing control methods fall short of addressing these issues, leading to vulnerabilities that can compromise naval operations. This work proposes a comprehensive control, merging primary and secondary controls for DC-NSMGs. The primary control adopts complex droop control (CDC) for adaptable power sharing, while the secondary control diverges from the state-of-the-art proportional integrator (PI) controller to a robust nonlinear model predictive control (NMPC) to handle disturbances. The proposed controller leverages the Lyapunov function to ensure recursive feasibility and asymptotic stability. Simulation-based experiments and real-time verification with extensive stability analysis validate the effectiveness of the control strategy. The findings demonstrated successful power sharing and voltage stability with 75% faster stabilization and a mean absolute percentage error (MAPE) as low as 0.02% compared with conventional controllers.