Study On Control Strategy For ISG Hybrid Electric Vehicle At Drive Condition

Hybrid electric vehicle is the most feasible clean economiacal vehicle which becomes one of the research hotspot in automotive industry at present. But it's complicated to distribute the power and manage the energy because the hybrid electric vehicles are always drived with two different power souces. When the basic configuration and parameters are confirmed, the control strategy of hybrid electric vehicle will optimize the internal combustion engine operation to impove the fuel economy and emission performace, through optimizing the power flow beatween engine and motor. Therefore, the research on control strategy is very important to exert the advantages of hybrid electric vehicle.Using the ISG hybrid electric vehicle with CVT as the research object, the control strategy of ISG hybrid electric vehicle at drive condition was researched and the fuzzy control strategy was also established in this paper.The numberical model of hybrid electric vehicle was built firstly in this paper. Based on the experiments of engine, ISG motor and NiMH battery, the numberical model of each power assembly was accomplished through analyzing the test data. Then, the operation modes of ISG hybrid electric vehicle were analyzed, and the equivalent model of vehicle was built based on the numerical model aiming at the minimum equivalent fuel consumption. And the Sequential Quadratic Programming (SQP) was used to compute the optimization problem.However, the conventional optimization methods are sensitive to the system error and depend on the exact model. The optimization results are always different to actual value because of the difficulty to build the exact mathematic model for hybrid electric vehicle. The fuzzy control technology is very suitable for hybrid vehicle control, and it's tolerant to imprecise measurements and component variability. But the establishment of fuzzy control rules is affected by unsure factors. Therefore, two methods were used in this paper. The fuzzy control was used to optimize the control strategy of hybrid vehicle using the results of SQP as instructions. And the fuzzy control strategy was abtained aimming at the minimum fuel consumption of vehicle.Based on the anlysis of modeling process for ADVISOR software, the simulation model of ISG hybrid vehicle was accomplished by second development of ADVISOR combine with the actual car. The control strategy established in this paper was...