Adaptive Stability Droop Control in DC Shipboard Microgrids Considering Battery States

This paper presents an adaptive stability droop control method that considers battery states for DC shipboard microgrids (DC SMGs), aiming to enhance DC bus voltage stability and ensure healthy battery operation. First, a full-order model incorporating battery dynamics is developed for the DC SMG system. A novel battery state-dependent stability strength index is then proposed to quantitatively assess the impact of battery states on the system's large-signal stability. Furthermore, by integrating this stability strength index into the droop coefficient design, an adaptive stability droop control method based on battery states is introduced. In contrast to conventional droop control methods that use fixed droop coefficients, the proposed approach utilizes feedback from battery states and stability margins to ensure healthy battery operation while improving DC bus voltage stability under load fluctuations. The effectiveness of the proposed method is validated through simulation-based studies.