The Research On Fuzzy Logic Energy Management And Transmission Ratio Optimization Of Series-parallel Hybrid Electric Vehicle

With the rapid development of world economy,energy shortage and environmental pollution problems have been valued by many countries,and the air pollution caused by motor vehicle exhaust emission problems have become increasingly prominent,in order to reduce automobile exhaust pollution caused by various car manufacturers to develop new energy vehicles.Hybrid hybrid electric vehicles have all the advantages of parallel series and parallel structure,which can adapt to various complex road conditions.But because the hybrid complex vehicle structure,energy management and parameters is very important,in order to achieve this goal,the need for coordinated control of multi energy source and the corresponding control.Therefore it is necessary to develop a control strategy with general characteristics and control strategies to meet the needs of different driving styles and road conditions with the help of more intelligent control strategies.Based on the hybrid vehicle to improve fuel economy for the purpose of expansion energy management research,distribution of regenerative braking and gear ratio optimization study,the specific work is as follows: according to the characteristics of the hybrid,with its main energy power,and the key parts of the modeling as the foundation,through to solve the nonlinear fuzzy logic algorithm for fuzzy quantity developed to improve fuel efficiency and can be used in actual engineering fuzzy control strategy,in order to obtain the best working curve of the engine and taking into account the battery and motor power and efficiency as the core,the establishment of Matlab fuzzy logic management principle and algorithm of allocation of energy between the two;then in the regenerative braking energy of fuzzy algorithms.To make up for the loss of car energy,extend the driving range;finally on the transmission ratio to optimize,to further improve the whole Vehicle fuel efficiency.Specific analysis is as follows:On the basis of hybrid HEV model,according to the working mode,design with SOC,speed V,demand torque T_req input,the P1 engine power and motor power P2 fuzzy logic output management rules,then according to the input and output,using stateflow to establish the fuzzy hybrid electric vehicle mixed logic under different drive mode switching logic in combination conditions,with embedded into AVL-Cruise fuzzy control strategy for power allocation based on the simulation of the vehicle will result in power as the core and auxiliary control strategy,show the fuzzy control strategy is more reasonable in power the distribution of fuel and power,by improving effect.By the fuzzy logic distribution recycled energy and friction energy also achieve the desired effect.The transmission of particle swarm optimization is introduced in Cruise on vehicle performance was improved;the shift becomes more smooth,which can improve the power of electric vehicles,but also can reduce the energy consumption.