Optimal Operation Strategy Considering Energy Management For Hybrid Power Train

At present,the mileage of non-electrified railway lines accounts for about 35%of existing railway lines mileage.Existing non-electrified lines are difficult to be electrified in short terms.In order to meet operation requirements,a large number of non-electrified locomotives are still needed,which especially represented by diesel have a low energy efficiency and produce inevitable environmental pollution.In this context,a new type of energy-efficient hybrid power train equipped with on-board energy storage system has come into being.This thesis presents a train optimal operation strategy with the consideration of energy management for a class of hybrid train,namely to realize the full use of regenerative braking energy for energy saving and utilize energy storage device rationally on taking the operation control and train power distribution into consideration.Firstly,with the introduction of the relationship between power system structure and energy flow,train traction calculation model and the on-board energy storage device equivalent circuit model are built.Optimization models in the electrified section and the non-electrified section are established with the goal of minimal sum of energy consumption and on-board energy storage's usage.Based on the different power supply modes and line characteristics,the classification principles of phase which is divided by power supply modes conversion point,velocity limit conversion point and parking point are presented,then the multi-phase optimization model is established.With the introduction of adaptive pseudospectrum method and the use of GPOPS-? toolbox,the solution to the optimization problem can be achieved.On the basis of the multi-phase optimization model and its solution,the actual data of hybrid train is applied to the simulation in the single electrified as well as single non-electrified interval to verify the validity of the model and the solution,and the optimal operation strategy of the hybrid power train can be achieved.The effects of the key factors such as the power constraints,the line conditions and the charging/discharging capacity of the on-board energy storage device are analyzed.Finally,the feasibility analysis of the timetable optimization is derived and with the improvement of the multi-phase optimization model,the model of optimal timetable control is established.The effectiveness of the optimal timetable model is verified by comparing the simulation results of optimal timetable with the results of original timetable.The results show that the sum of the energy consumption and the on-board energy storage's usage of optimal timetable is decreased by 4.59%.