Time-frequency domain transformation dynamic hydrogen-electric energy network for efficient power coordination and economic scheduling in zero-emission ship power systems

The urgent need for low-carbon transformation in shipping has made hydrogen-driven ships a key development direction owing to their zero-emission characteristics. However, existing hydrogen-electric systems face challenges in dynamic power coordination owing to sluggish fuel cell (FC) responses and unstable operation under variable loads. This study proposes a dynamic hydrogen-electric energy network model featuring an original time-frequency domain transformation that converts hydrogen network partial differential equations (PDEs) into frequency-domain algebraic equations. This transformation reduces the computational complexity and improves the solution efficiency compared with traditional solvers, thereby enabling real-time optimization. Integrated with a mixed-integer linear programming (MILP) framework, the model coordinates FC and lithium battery dispatch under dynamic hydrogen constraints (pressure, flow). The results demonstrate a reduction in the FC power fluctuation rate from 0.595 to 0.274, a 4.89% decrease in generation and hydrogen consumption costs, and a 37.5% reduction in battery start-stop costs. The system adaptively shifted the FC base-load contribution from 91.23% to 85.37%, increasing the battery regulation share from 8.77% to 14.63%. A “rigid constraint, flexible adjustment, safe relaxation” strategy demonstrated feasibility during transients within the numerical simulation framework. This study provides a new theoretical foundation for intelligent hydrogen-electric management in zero-emission ships.