Simulation Research On Torque Coordination Control Strategy Of Parallel Hybrid Electric Vehicle

With the development and progress of society,the problems of environmental pollution and energy depletion become increasingly serious,and new energy vehicles have become the focus of the development of automobile industry.Hybrid electric vehicle,as a new energy vehicle,combines the advantages of both traditional fuel vehicles and pure electric vehicles.It has the advantages of long cruising range of traditional fuel vehicles and low emission performance of pure electric vehicles,and is a new energy vehicle with the most development prospect.However,the hybrid electric vehicle has both engine and motor,which makes the hybrid electric vehicle have multiple operation modes,thus making the control strategy more complex.The research on the control strategy of hybrid electric vehicle plays an important role in improving the performance of the whole vehicle,which is the focus of current research.In this dissertation,the prototype of the prototype vehicle being developed by Dongfeng Xinjiang Automobile Co.,Ltd.,aiming at the problem that the traditional control strategy of parallel hybrid electric vehicle(PHEV)can not optimally distribute the required torque of the whole vehicle to the engine and motor-driven vehicles under complex working conditions,and aiming at improving the fuel economy and exhaust emission performance of PHEV,the coordinated control strategy of PHEV torque is studied.Specific research contents are as follows:(1)Through the analysis of three basic structures of hybrid electric vehicles,namely series,parallel and series-parallel drive systems,PHEV is selected as the research object.According to the energy flow direction of PHEV in different operation modes,the torque and power distribution modes of automobile in different operation modes are determined.According to the basic parameters and performance indexes of the prototype car,the main components of PHEV drive system(engine,motor,battery,etc.)are analyzed by parameter matching and modeling.(2)To solve the problem of coordinated torque distribution of PHEV,the principle of motor auxiliary control strategy commonly used by PHEV is analyzed firstly.Secondly,according to the fuzzy control principle,the fuzzy control strategy is proposed,and the simulation model of fuzzy control strategy is built based on MATLAB/Simulink simulation platform.(3)Through the redevelopment process of ADVISOR2002 automobile simulation software,the simulation models of two control strategies are embedded into the whole vehicle simulation model of the software respectively.According to the designed simulation parameters and selected cycle conditions,the simulation is carried out in ADVISOR2002 software.Comparative analysis of simulation results shows that the fuzzy control strategy has more efficient average working efficiency,better fuel economy and exhaust emission performance than PHEV under motor auxiliary control strategy.(4)In view of the deficiency of fuzzy control strategy,particle swarm optimization(PSO)algorithm is used to further optimize the fuzzy control strategy,and PSO algorithm is used to optimize the membership degree and control rule weight of fuzzy controller.The optimized fuzzy control strategy is re-embedded into the whole vehicle simulation model of ADVISOR2002 software,and simulation is carried out under the same simulation parameters.The simulation results show that the optimized fuzzy control strategy has better control effect.