Research On Power System Parameter Matching And Control Strategy Of Extended Range Electric Vehicle

The automobile industry is constantly promoting the transition to electric vehicles due to issues with energy exhaustion and environmental pollution.It is currently unable to fully realize the electric vehicle transition in the short term due to the technical limitations of the power battery limit the range of electric vehicle,however,the extend-range electric vehicles can not only drive in pure electric mode,but also through the range extender to improve mileage,is one of the ideal transition vehicles.The correct matching of power system parameters of extended range electric vehicles can effectively improve the vehicle performance,and the control strategy has a significant impact on the vehicle power and economy.Therefore,this paper studies the power system parameter matching and control strategy of extended range electric vehicle.The extended-range electric vehicle is the subject of this study.To achieve the best performance,the parameters of the power system components are matched according to the basic parameters of the vehicle and other major indicators.,the advantages and disadvantages of the single-point control strategy and the power-following control strategy are analyzed in combination with the basic structure and control strategy design principle.Considering the fuel consumption of the engine and the life of battery,the multi-point control strategy of the engine is developed.In order to recover the energy in the deceleration brake as much as possible,the energy recovery control strategy is formulated.The vehicle model and the control strategy model were subsequently constructed using the AVL Cruise software and MATLAB/Simulink software,respectively,the co-simulation is carried out by integrating the control strategy with the vehicle model,the results show that under NEDC working condition,WLTC working condition and CLTC working condition,the actual velocity can well follow the expected velocity curve of the working condition,and then simulate the power performance of the vehicle by establishing a slope-climbing computing task and full load acceleration task at AVL CRUISE,the driving range of the vehicle is calculated by NEDC cycling conditions and 90km/h cruising conditions.The simulation results show that the power performance and economic performance of the vehicle are better than set performance indicators.The effectiveness of the energy recovery and multi-operating point control strategies was subsequently verified by simulation results,and a comparison to the single point control method was analyzed.The simulation results show that although the comprehensive fuel consumption of the single-point control strategy is lower than that of the multi-point control strategy,however,the charging and discharging times of the power battery under the single-point control strategy are more than under the multi-point control strategy,and the charging power of the battery is relatively large,thus reducing the battery life.Comprehensive show that the multi-point control strategy formulated in this paper is better than a single-point control strategy.In order to further improve the vehicle performance,this paper selects the transmission ratio of the main reducer as the optimization variable,the acceleration time from 0 to 100km/h and fuel consumption per 100 kilometers are used as the objective function,and establishes the corresponding constraint conditions.The non-dominated sorting genetic algorithm with elite strategy(NSGA-II)is selected as the specific optimization algorithm,and Isight software and Cruise software are used for co-simulation,the optimized transmission ratio is obtained.The optimization results show that the optimized maximum velocity is reduced by 7.5%,the acceleration time from 0 to 100km/h has decreased by 1.5%,the maximum climbing slope is increased by 9.9%,and the comprehensive fuel consumption is reduced by 1.1%.The optimized transmission ratio can not only meet the power performance of the vehicle,but also improve the economy to a certain extent,which makes the overall vehicle performance improved.