Energy Management Research Of Hybrid Electric Vehicles

A provided Matlab/Simulink prototype model of a PHEV in cooperation with the Hanteng Automotive Corp.was investigated to optimize and improve the energy management.The model was simulated under NEDC conditions.Major consideration were the fuel and the electric energy consumption.This thesis investigated the influence of the gear shifting velocities,by variation of a gear coefficient.The initial gear coefficient equaled 1 and was varied in the range from 0.5 to 1.5.Decreasing the initial gear coefficient led to a higher fuel consumption and showed no tendency for the battery SOC.Increasing the gear coefficient led to a decreased fuel consumption as well as a decreased SOC.Furthermore,to smooth the oscillating operation of the engine a rule-based stateflow structure of the torque distribution model was developed and a hysteresis signal changing structure was added.The variation of the hysteresis interval showed an improvement of the engines performance with increasing interval values.But changing the gear coefficient,especially to lower values,showed an improvement of the oscillating performance as well.Moreover,a variation of the interval influenced the fuel and electric energy consumption.The simulation results from variation of gear coefficient,hysteresis interval and their combination were compared with calculated values according to the UNECE Regulation No.101 for PHEVs.