Optimization of Energy Management Strategy for Hybrid Power System of a Liquid Cargo Ship

To enhance the potential application of ships in energy conservation and emission reduction, a parallel hybrid power system simulation model was developed using Matlab/Simulink based on the operational scenario of a 3300 m3 inland LPG tanker. A rule-based control strategy was employed to simulate and analyze the impact of different power modes on the energy efficiency and emissions of the ship’s power system. An optimization method for an energy management strategy based on the ship’s operating cycle was proposed. The results show that using an LNG engine as the main engine in the hybrid system significantly reduces fuel consumption and pollutant emissions throughout the ship’s operating cycle. When the hybridization ratio is 0.2, the system achieves relatively optimal overall energy consumption and emission levels. Building on this, an Equivalent Consumption Minimization Strategy (ECMS) was introduced, and multi-objective optimization was carried out using an improved particle swarm optimization algorithm. Additionally, reinforcement learning was applied to optimize the energy management strategy, resulting in further reductions in fuel consumption over the operating cycle.