Research On Capacity Allocation And Energy Management For Diesel-battery Hybrid Train

With the continuous maturity of power battery technology,diesel-electric hybrid trains with diesel generators and power batteries as power sources are more green and environmentally friendly than traditional diesel locomotives,and are a promising new type of rail transit running on non-electrified railways Shipping method.Capacity allocation and energy management strategies are the key technologies of hybrid electric trains.Reasonable capacity allocation can improve the operating economy of trains in the whole life cycle.Appropriate energy management strategies can improve train fuel efficiency and reduce train operating costs.This thesis takes the hybrid power system of the hybrid electric train as the main research object.First,the energy flow mode of the hybrid power system is analyzed.From the perspective of energy flow,the train dynamics model,diesel generator model and power battery related models are built.The choice of the capacity configuration of the hybrid system and the design of the energy management strategy provide the basis for the model.For the capacity configuration of the hybrid power system,this thesis considers the historical distribution of the traction mass of the train,and uses the global optimization strategy of the Pontryagin minimum principle as the control method of power allocation,and uses the total life cycle total cost weighted by the traction mass distribution.The minimum as a basis for selection determines one of the 225 preset alternative configuration parameters as the configuration parameter of the hybrid system.For the energy management strategy of the hybrid power system,considering the poor robustness of Pontryagin’s Minimum Principle strategy and the difficulty of applying online value,resulting in an improved minima principle strategy with a PI controller.In order to take into account the fuel economy and power maintenance of the improvement strategy,this thesis takes the minimum equivalent fuel consumption weighted according to the traction mass distribution as the optimization goal,and takes the power battery SOC within a certain range at the end of the operation as the constraint condition with the help of genetic algorithm.The three parameters of the strategy are optimized.The simulation results show that the improved minimum value principle strategy after parameter optimization can achieve reliable maintenance of power battery SOC under different train traction quality operating conditions and different initial SOC conditions,and also has good fuel economy.Not only that,the strategy also has good fuel economy,which is shown in the fact that the strategy has a fuel saving rate of about 3.4%-4.1% compared with the traditional threshold control strategy under different traction quality conditions,which is closer to The off-line minimum principle strategy has a fuel saving rate of about 3.7%-4.2%.