A novel cooperative optimization method of speed and power allocation for the fully rotational electric propulsion ship

Abstract

Energy consumption optimization for the fully rotational electric propulsion ship is crucial for energy saving and emission reduction, and hence achieving the low-carbon development of the shipping industry. However, there is currently a lack of effective energy consumption models and cooperative optimization methods for fully rotational electric propulsion ships, which limits improvements in the ship energy efficiency. Therefore, a method for the cooperative optimization of sailing speed and power allocation considering changes in sea conditions is proposed. Firstly, a nonlinear optimization model for ship energy consumption considering time-varying sea conditions is established. Then, a cooperative optimization model for the sailing speed and power allocation is established to achieve the minimum ship energy consumption. In addition, the NSGA-II optimization algorithm is adopted to achieve the cooperative optimization of the sailing speed and power allocation for the fully rotational electric propulsion ship. Finally, a case study is carried out to validate the effectiveness of the proposed method. The results indicate that the energy consumption and emissions of the fully rotational electric propulsion ship can be reduced by 4.17 % through adopting the proposed cooperative optimization method. In addition, the comparison analysis results show that the NSGA-II algorithm achieves better energy savings than the Differential Evolutionary (DE), Particle Swarm Optimization (PSO) and Genetic Algorithm (GA). Therefore, the NSGA-II algorithm has its superiority over other algorithms for the energy consumption optimization of the fully rotational electric propulsion ship.