Parameter Matching And Optimization Of Power System Driven By Dual Axis With Dual Motor

Regarding the advantages of energy saving,pollution-free,and low noise,pure electric trucks have developed quickly under the situation of increasingly fierce competition in the logistics industry,and in some large cities,they have gradually replaced some fuel trucks.Currently,pure electric trucks are mostly driven by a single motor,which have simple structure and is easy to control.Nevertheless,on account of the low energy density and the heavy weight of the unit volume of power battery,bring about the poor endurance.It must be necessary to improve and strengthen their ability of endurance,if the pure electric trucks want to further replace the fuel trucks.For the sake of addressing the problem of poor endurance ability issue,this paper transforms single motor single shaft dynamical system into double motor and double axle dynamical system,formulates reasonable drive control strategy,using optimization algorithm optimize the multiple parameters,further enhance the performance of the vehicle.The following is the main research contents:(1)Several dynamical system configurations are compared and analyzed,and the configuration of double motor and double axle is selected.According to the vehicle’s dynamic requirements,the dual-motor power distribution method,in which demand power is distributed according to frequency,was adopted to match the parameters of the two motors.The parameters of the power battery were matched according to the cycle mileage requirements.(2)The characteristics of various working modes of the dual-motor dynamical system are analyzed and the instantaneous power of the motor of each driving mode is calculated.Combined with the working characteristics of various driving modes,the minimum instantaneous power of dual motors was taken as the optimization objective,and the drive pattern recognition and torque distribution control strategy of dual motors was proposed.(3)Based on model of pure electric truck driven by dual motor and dual axis on CRUISE,the control strategy for dual motor power system is established.the simulation results show that double motor dynamical system of maximum gradability and acceleration time are better than the single motor dynamical system,energy saving effect increased by 9.4%,It is proved that the design of dual-axis dynamical system and control strategy are reasonable.(4)CRUISE software is embedded into ISIGHT software to optimize several parameters with 0-50km/h acceleration time and C-WTVC cycle power consumption as optimization objectives.Multi-island GA was used to optimize power battery voltage,main deceleration ratio and peak torque of two drive motors.The optimized values of the four variables were imported into CRUISE model.The simulation results show that the optimized dual-motor and dual-shaft dynamical system can reduce the power consumption by 3.68% and increase the range by 14 km in C-WTVC cycle compared with that before optimization,which proves that the optimization is reasonable.