The Study On Energy Management Strategy Of Single Planetary Hybrid Vehicle

Under the condition of the increasing environmental problems and the shortage of oil resources,the automobile industry has also stepped into the ranks of major reforms.Hybrid vehicle,which has the advantages of ultra long range and pure electric green emission,is the mainstream new energy vehicle in the current society.Among them,the single planetary row hybrid electric vehicle combines the advantages of series and parallel in the hybrid structure,which can realize the decoupling of engine speed and speed,make the adjustment range of engine working point wider and the overall fuel consumption lower.Because the hybrid has multiple power sources at the same time,how to start and stop the power source reasonably according to the real-time working condition and how to achieve the expected fuel economy of the whole vehicle is an urgent problem to be solved.Therefore,based on the characteristics of the vehicle power source,the establishment of the vehicle controlled model and the realization of simulation under the reasonable energy management control strategy are the focus of this paper.The specific contents are as follows:Firstly,the dynamic analysis of the speed,torque and power of the single planetary row hybrid power diverter is carried out,on this basis,leverage method is used to analyze the process of various operation modes of the whole vehicle in detail,providing theoretical basis for the establishment of energy management strategy.In addition,according to the principle and method of dynamic parameter matching,the power source is selected,which lays the foundation for the controlled object modeling.Secondly,based on the optimal curve energy management strategy of the engine,this paper models,mainly including the calculation of wheel power request,engine start and stop control,the determination of vehicle working mode and switching rules,and the energy allocation of the engine,MG1 and MG2.Finally,the vehicle model built by Cruise and the control strategy built by Simulink are configured to realize joint simulation.The results show that under NEDC condition,the vehicle speed follow and torque response effect of power source are better,the change of SOC is stable in the set threshold range;under HWFET condition,the vehicle’s working mode switches smoothly under the engine optimal curve control strategy,making the engine work in the high efficiency range all the time,and the fuel saving effect also reaches the expected goal.Finally,the fuzzy PI control is introduced to further optimize the engine speed control,taking the engine speed deviation and deviation change rate as the input,fuzzy,fuzzy rulemaking and anti fuzzy processing are carried out,and then the completed fuzzy controller is transferred to the Simulink environment and combined with Cruise again for simulation.The results show that after the fuzzy PI optimization,under NEDC and HWFET condition,the engine’s working point is concentrated near the optimal fuel economy curve,and the overall fuel consumption is 6.14% lower than before.At the same time,the MG1’s working point distribution is more centralized and the efficiency is higher,which meets the expectation.