Research On Interval Optimal Allocation Of Energy Storage Systems Of The All-Electric Propulsion Ship

With the rapid development of the global economy,the consumption of fossil fuels has been increasing year by year.In order to address the energy shortage and environmental pollution caused by this,clean energy represented by electric power has been widely applied in the field of shipping.All-electric propulsion ships can solve the problem of low energy utilization and high operating costs of traditional ships.However,uncertain marine environments and weather factors severely affect the power generation and navigation status of all-electric propulsion ships,in order to achieve more efficient and economical navigation of all-electric propulsion ships.This paper takes the all-electric propulsion ship as the research object and fully considers the uncertainty during the ship navigation process,and conducts research on the optimization of energy storage allocation for all-electric propulsion ships covering uncertain factors.This paper establishes mathematical models for the all-electric propulsion ship diesel generator system,photovoltaic power generation system,energy storage system,and ship propulsion system.Considering the problem of increased operating costs for all-electric propulsion ships due to uncertain factors during navigation,a speed attenuation mathematical model is established for all-electric propulsion ships that includes uncertain parameters such as wind speed,wave length,and wave height.The impact mechanism of uncertain factors on ship power generation and navigation is analyzed.To address the drawback of high operating costs for all-electric propulsion ships caused by uncertain factors,the paper applies the interval analysis method to deterministically handle the uncertain parameters in the optimization model.This results in the establishment of an interval optimization model for all-electric propulsion ships,which includes a speed attenuation interval mathematical model.The interval order method and interval possibility method are used to deterministically transform the objective function and constraint conditions of the model containing uncertain parameters.The nested particle swarm optimization algorithm is used to solve the double-layer model after deterministic transformation.The inner particle swarm optimization algorithm solves the interval variables of the model,and the outer particle swarm optimization algorithm solves the decision variables of the model,resulting in the coupled optimization of energy storage allocation and navigation status for all-electric propulsion ships with uncertain parameters.The results show that the total operating costs of all-electric propulsion ships are reduced through optimized energy storage configuration.The installation of a photovoltaic power generation system on an all-electric propulsion ship can reduce the total output of diesel generators and further reduce the total operating costs of the ship.In order to provide ship operators with multi-angle operating plans,this paper establishes a multi-objective interval optimization model that covers the cost of diesel generators and the installation and operation costs of energy storage systems.Based on the nested particle swarm optimization algorithm,a non-dominant solution set layering method is introduced to solve the multi-objective interval optimization model,and the non-dominant solution set of the all-electric propulsion ship is obtained.The results show that after introducing the photovoltaic power generation system,the all-electric propulsion ship can reduce the cost of diesel generators and the installation and operation costs of energy storage systems through energy storage optimization configuration,on the basis of completing the expected sailing plan,making the all-electric propulsion ship more economically efficient.The research in this paper helps to enrich the theoretical and technical system of energy storage optimization configuration for all-electric propulsion ships.