Dual-layer cooperative power control architecture for shipboard DC microgrid with gas turbine-photovoltaic-hybrid energy storage

Aiming at the coordinated operation challenges and DC voltage stability issues in shipboard DC microgrids caused by significant fluctuations in output of renewable energy, intense variations of propulsion load, and slow transient response of the gas turbine (GT), a dual-layer cooperative control strategy is proposed in this paper. A ship-integrated energy system combining GT, photovoltaic (PV), lithium battery and supercapacitor is constructed. Firstly, a primary power allocation method based on the low pass filter is employed, allocating high-frequency power to the supercapacitor for fluctuation suppression. The remaining power then is allocated by the battery and GT according to rules dynamically to ensure the coordinate operation of the shipboard DC microgrid. Secondly, a supercapacitor power secondary correction method based on fluctuation thresholds of the bus voltage is designed to maintain voltage stability during GT switching. The dynamic response characteristics of the system under different conditions are investigated based on the Matlab/Simulink platform. Results indicate that the proposed method ensures coordinated and stable operation of the system, reduces specific fuel consumption by optimizing the power-generation efficiency of the GT, and effectively mitigates DC bus voltage fluctuations caused by GT switching. When the GT is connected to the grid, the maximum fluctuation rate of the bus voltage is reduced from 17.3 % to 3.1 % and the time for the bus voltage to recover to its rated value after the GT is disconnected is reduced from 17.45 s to 1.04 s. • Dual-layer control for multisource shipboard DC microgrid stability and efficiency. • PV-GT dynamic synergy minimizes emissions at low loads. • Hybrid energy storage (battery-supercapacitor) suppresses voltage fluctuations to 3.1 %. • GT switching recovery time reduced from 17.45 s to 1.04 s via secondary correction. • Validated robustness under ship acceleration, deceleration, and emergencies.