Research On Power Matching And Energy Optimization Of Dual Planetary Row Hybrid Electric Bus

In the face of resource shortage,environmental pollution and increasingly perfect emission standards,domestic and foreign research and development of hybrid electric vehicle technology has also invested a lot of energy.The hybrid electric vehicle has the advantages of series hybrid and parallel hybrid electric vehicle.By changing the working state of power source and other parts and the configuration of transmission system,it can realize multiple working modes.At the same time,the hybrid system has higher requirements for vehicle control strategy.This paper takes a heavy hybrid bus as the research target,and focuses on the working characteristics of the power configuration,and designs a set of energy management strategy to improve the fuel economy of the bus.Firstly,the vehicle configuration of hybrid electric bus is analyzed,the characteristic equation of dual planetary row power coupling mechanism is established,and the energy flow and working state of engine,motor and clutch under various working modes is analyzed,and then the selection and power parameter matching of each component according to the constraints of vehicle dynamic performance and pure electric driving range is completed.Secondly,the vehicle energy management control strategy based on the optimal working curve of the engine is designed.The steady-state dynamic equation is established based on the lever method theory,and the power source torque is distributed under each working mode.The compensation torque of motor MG1 is adjusted by PID algorithm to control the engine speed,so as to coordinate the engine working in the low fuel consumption area as far as possible.Then the whole vehicle model is built,and the simulation model of vehicle closed-loop system is completed combined with the designed energy management strategy model.The rationality of the system model is verified by analyzing the simulation results of power performance and fuel economy under standard conditions.Finally,in order to further reduce fuel consumption,the dynamic performance index and the characteristics of the dynamic coupling mechanism of the double planetary row as the constraint conditions,and taking the 100 km equivalent fuel consumption as the objective function,the parameters of the transmission system are optimized based on DOE full factor experimental design.The results show that the equivalent fuel consumption per 100 km is reduced by about 6.41%,but with the improvement of fuel economy,part of the power performance is also sacrificed.Therefore,the parameters of the transmission system should be set reasonably considering both power and economy.