Research On Energy Management Strategy Of Plug-in Hybrid Electric Logistics Vehicle Considering Thermal Characteristics

With the energy-saving transformation of the automobile industry and the rapid development of the logistics industry,plug-in hybrid logistics vehicles have been paid special attention because they have achieved a good balance between driving range and dependence on oil.For the plug-in hybrid logistics vehicle,the working states of its powertrain components are greatly affected by temperature.Too high or too low temperature will reduce the efficiency of the power system and increase the energy consumption of the whole vehicle.Therefore,considering the thermal characteristics of the system in the energy management strategy will improve the working states of the powertrain components,thereby improving the fuel economy of the whole vehicle.Around this topic,the paper will be divided into the following contents:(1)Establishment of the power system model of the hybrid logistics vehicle.The paper takes a plug-in hybrid logistics vehicle with the planetary hybrid configuration as the research object,builds the mechanical electrical thermal coupling simulation model of the power system including engine,motor and battery based on the MATLAB/Simulink platform,and analyzes the thermal characteristics of the components based on the traditional power system modeling.It lays a foundation for the subsequent modeling of the thermal management system and the formulation of the energy management strategy considering thermal characteristics.(2)Establishment of the thermal management system for the power system.Firstly,the system architecture is determined according to the heating and cooling requirements of the thermal management requirements of the power system to design the system scheme,and then the dynamic heat transfer model is established according to the heat transfer in the system.The radiator and other components in the thermal management system are modeled on the MATLAB/Simulink platform,the system control strategy is designed.Afterwards,simulation verification and analysis were carried out in high-temperature and low-temperature environments,to achieve good control of the temperature of each component of the power system and analyze the energy consumption of the thermal management system.The results show that the energy consumption of the thermal management system in the high and low temperature environment accounts for 7.04% and 12.77% of the total vehicle energy consumption respectively,the energy consumption of the system at low temperature accounts for 9.83% of the energy consumption of the vehicle,which is a certain improvement.(3)Research on energy management strategy considering thermal characteristics.Combining the thermal characteristics of the system with the equivalent consumption minimization strategy,a research plan for the optimal control strategy of vehicle energy management considering thermal characteristics is proposed.Firstly,the overall energy management control scheme of CD-CS is clarified.Then,in the CS stage,the equivalent fuel consumption minimum strategy is applied,and an improved adaptive equivalent factor adjustment method considering the thermal characteristics of the system is proposed.By establishing the Hamiltonian function to achieve the goal of minimum equivalent fuel consumption,considering the temperature penalty,the power of the engine and the power of the battery is reasonably allocated.(4)Verification and comparative analysis of energy management strategies considering thermal characteristics.Firstly,the effectiveness of the developed energy management optimization strategy considering thermal characteristics is verified,and then the optimization strategy is compared with the traditional strategy to analyze the fuel-saving mechanism of the optimization strategy and verify the fuel-saving effect.The results show that,compared with the traditional strategy,the optimization strategy proposed in this paper can reduce the fuel consumption by 6.2% in the high temperature environment,and the fuel saving effect is more obvious in the low temperature environment,which is reduced by 8.4%.