Control Strategy for Double Motor Electric Vehicle

  Abstract: The control strategy of double motor electric vehicle was formulated. Firstly, the battery energy management strategy was constructed by using of instantaneous optimization algorithm for maximum efficiency. Secondly, the all-wheel drive control strategy was built includes dynamic distribution strategy, stability distribution strategy, anti-skid distribution strategy and economic distribution strategy. Lastly, the simulation evaluation of dynamic performance and economic performance were conducted based on the MATLAB/SIMULINK platform. The results indicate that four-wheel drive has better dynamic performance and less economic performance. The front motor or rear motor drive only has better economic performance.

1. Introduction
The electric vehicle (EV) can obtain zero emission and save use cost, which get attention deeply by different countries, car enterprise and scientific research structure. An optimization strategy of acceleration torque control

 [1] for pure electric vehicle is proposed based on fuzzy control, A dual-objective optimization method based on MOGA-Ⅱ genetic algorithm

 [2] is proposed for the ratio of power train to be matched reasonably to the drive motor of pure electric vehicle. A pure electric car ownership system dynamics model was established, and the trend of the development of pure electric vehicles was simulated

 [3]. The torque optimal control

 [4]problem of pure electric vehicle was studied.
 

 In this paper, the battery energy management strategy is firstly constructed by using of instantaneous optimization algorithm for increasing driving mileage. Secondly, the four-wheel drive control strategy is obtained based on the dynamic target. Lastly, the simulation results are analyzed for checking dynamic performance and economic performance in different driving cycle based on MATLAB -SIMULINK platform.

 The paper is organized as follows. In the next section, we propose the powertrain structure of double motor electric vehicle that we research in this paper, and some parameters are given. In Section 3, the battery energy management strategy and all-wheel drive control strategy is built. Then we finish the dynamic and economic simulation analysis based on MATLAB -SIMULINK platform. Finally, we conclude our paper in section 4.

2. Powertrain structure and parameters
  The powertrain system is composed of front motor, rear motor, and battery. The vehicle structure of PHEV is shown in Fig.1. Parameter values and specifications for the PHEV model are provided in Table 1. HCU (Hybrid Control Unit) can control front motor and rear motor to realize the all-wheel drive (AWD) mode, front- wheel drive (FWD) mode, and rear-wheel drive (RWD) mode.