Control Strategy And Simulation Analysis Of Dual-motor Coupling Drive System For Pure Electric Vehicles

For pure electric vehicles,the most important thing is the cruising range compared with the traditional car and the battery capacity of the cruising range directly affects the cost of the whole vehicle.In the current situation,with no breakthrough in battery technology,improving the energy utilization rate of pure electric vehicles is a more effective way to extend CRUISE range.There are two main ways to improve the utilization rate of electric vehicles: firstly,based on the traditional single-motor drive structure,the vehicle lightweight design and energy recovery technology are optimized by optimizing various parameters of the vehicle and optimizing management of the motor battery.Secondly,the new configuration of the pure electric car was promoted,which consists of a single motor with multiple speed ratio,dual-motor coupling drive,wheel motor drive and so on.In this paper,according to a dual-motor coupling drive electric car,a logical judgment control strategy for which is proposed.According to the structure and working principle of the specified dual-motor configuration,the system is divided into eight modes and the control strategy of switching between different working modes is established.The Simulink model of the control strategy and the CRUISE model of the vehicle simulation are built and co-simulation verification is performed later on.Finally,the multi-island genetic control algorithm is used to optimize the four calibrations.The main contents of this paper are as follows:1.The configuration of the dual-motor drive system and the working state of low speed light load,low speed heavy load,medium speed light load,medium speed heavy load,high speed,low speed brake,medium speed brake and high speed brake are analyzed.At the same time,the relationship between input and output speed and torque are analyzed.Parameter matching is performed according to the design goal.2.The control strategy built by Matlab/Simulink is imported into CRUISE through DLL file,in which the whole vehicle model is set up.It is verified whether the dynamic performance and economical efficiency of the model meets the design goals.3.The mode switching control strategy is adopted,according to the real-time vehicle speed,pedal information,load signal.Motor/planetary speed signal is inputted to the universal variable calculation module and the processed signal is outputted to the mode judgment module,and the mode judgment module makes a judgement based on the gate valve and the input variable whether the mode code is outputted to the mode switching module.The mode switching module is used to control the working states of the motor M1,the motor M2,the clutch CL1,the clutch CL2,and the brake B,and finally the car can realize the mode switching control strategy and set up a control strategy in Matlab/Simulink.4.Isight and CRUISE is jointly simulated for optimization.In line with Isight's own multi-island genetic control algorithm,the four parameters of low speed switching high speed threshold,low speed light load switching heavy load threshold,medium speed switching high speed threshold,medium speed light load switching overload threshold are optimized.The economical efficiency of dual-motor coupling drive system are optimized.