Research On Safe Eco-Driving Control Strategies For Dual-Motor Electric Vehicles

Electric vehicles(EVs)have become the development direction of future vehicle for their low noise,zero emissions,strong power,and no fuel consumption.Energy saving and vehicle safety driving control strategies are still the eternal themes of its development.EVs of dual-motor have the potential to improve the overall efficiency of EVs by allowing flexible adjustment of the speed/torque coupling and decoupling operating states.As a result,EVs of dual-motor has the potential to remarkably improve the overall efficiency of EVs.High-efficiency dual-motor powertrain configuration design and energy management strategy optimization is a research hotspot in the field of electric vehicle energy efficiency and an important aspect of eco-driving research.On the other hand,there is a wide range of vehicle safety driving strategies that have been studied in order to reduce rear-end accidents caused by driver behavior while driving,besides the aforementioned eco-driving problems within the vehicle itself.To solve the eco-driving problems,a novel dual-motor multimode coupling powertrain(DMMCP)is proposed in this paper to improve the energy efficiency of EVs.The powertrain is based on a dual-motor with compound planetary device which provides two inputs for two motors to drive the vehicle.Specifically,DMMCP can achieve four driving modes which are two single-motor driving modes and two dual-motor driving modes.Further,the dynamics model of DMMCP was firstly established by the general characteristic equation of kinematics,and then the key parameters of DMMCP were designed based on this dynamics model by using an improved particle swarm optimization algorithm(PSO).A mode switching strategy based on the principle of instantaneous power optimization is designed under vehicle driving and braking conditions.However,in order to show the superiority of the powertrain proposed in this paper,a classic model produced by SAIC with Dual-motor torque coupling powertrain(ROEWE Marvel-X)is regarded as the comparison powertrain.To maintain the accuracy of the economic comparison,the mode switching strategy of ROEWE Marvel-X is optimized by the same principles of DMMCP.Finally,a simulation analysis under a variety of typical driving cycle conditions clearly shows that DMMCP has better economic performance.In addition,this paper also proposes a vehicle emergency braking control strategy for rear-end accidents when the vehicle interacts with the external environment,and demonstrates the effectiveness of the strategy through vehicle testing.