Online Cycle Optimization Of Energy Management Strategy For Hybrid Energy Storage Tram Based On Pontryagin's Minimization Principle

Modern trams have developed rapidly in large and medium-sized cities in China in recent years due to their large capacity,high speed,high safety and low energy consumption.In order to eliminate the impact of the catenary on the urban landscape,some trams use the energy storage technology of the vehicle,in which the hybrid energy storage system uses different energy storage components to work together,in power density and The energy density performed well.Based on this background,this paper studies the capacity configuration and energy management system optimization of hybrid energy storage systems for battery-supercapacitor hybrid energy storage trams.Firstly,the paper introduces the traction and braking characteristics of trams,analyzes the source of demand power,models and analyzes the hybrid energy storage system,introduces the working characteristics of energy storage components,and analyzes its working principle and derivation of relevant formulas.Compare the advantages and disadvantages of different topologies,select the appropriate topology,and set initial conditions for subsequent simulations.Secondly,this paper designs the multi-objective optimization of tram capacity configuration and analyzes the constraints of the actual operation of the tram.Using the parameters of the tram line of Wuhan Donghu Line,the power curve of the tram is calculated by traction calculation.On this basis,the trams are simulated against a variety of different online energy management strategies,and the particle swarm optimization algorithm is used to quickly optimize the capacity configuration.The MATLAB has been used to compile an independent capacity configuration software,which can optimize the capacity configuration of different lines and different HESS components,and increase the EMS verification interface to facilitate the simulation verification of the optimized capacity configuration results.This paper proposes to use the Pontryagin's Minimum Principle(PMP)to optimize the power curve obtained by traction and compare it with a fixed ratio of EMS.Because the actual effect of the HESS online EMS of the tram is poor,and the tram has a special right of road rights compared with electric vehicles and subways,this paper proposes a ground communication method to predict the running curve of the tram.In the process of tram operation,the running power curve of the next section is continuously predicted,so reciprocating,the online loop optimization is realized by the PMP extremum principle,and the simulation of the working condition prediction is carried out to realize the energy management strategy online.Adjustments verify the superiority of this strategy over fixed-scale strategies.Finally,a comparative experiment of energy management strategies was completed by a hybrid electric vehicle hybrid energy storage system prototype.In this paper,the improved dual-loop control strategy is used to implement different HESS power allocation strategies on the prototype.The EMS is adjusted through the DSP control board.By scaling the load power of the tram,the effectiveness of the online energy management strategy proposed in this paper is verified on the 90kW experimental platform.