Chuan Xue Song

Parameter Matching and Performance Simulation for a Distributed Power Extended-Range Electric Vehicle

In order to solve the problem of low power-mass-ratio and high curb-weight in existing extended-range electric vehicle, this paper proposed a distributed power design, and calculated the powertrain parameters of this design, which was based on a commercially available extended-range electric vehicle. Through parameter calculation and simulation, this design was proved to significantly lower the curb weight and manufacturing cost of an extended range electric vehicle, and improve the efficiency of regenerative braking at the same time, finally lead to longer mileage.

Study of Modeling and Simulation on Driving Force Power Steering for Electric Vehicle with In-Wheel-Motor-Drive

The most significant feature of EV with In-Wheel-Motor is that, the torque of each wheel can be controlled independently. [. When EVs turn, controlling torque of steering wheel independently can generate torque difference around the kingpin to reduce the drivers steering force and improve the steering Portability [. At first, the theory and structure of Driving Force Power Steering (DFPS) are discussed and a vehicle dynamic model is built with AMESim software. Based on the control strategy and algorithm a control model is built using Matlab/Simulink. At last, a simulation is performed. The results show that the DFPS system can provide steering power and assist steering efficiently.

Simulation and Paramatric Analysis of ABS for EV with Electric Brake

A simulation model of EV with the software of AMESim was established and the ABS control method with four independent channel by electric brake was designed in Simulink with the fuzzy logic control. The simulation is carried on under the low tire-road friction coefficient. The simulation results show that, the co-simulation model and its control method is able to simulate the actual ABS braking process, ensure the wheel speed well follow the vehicle speed, improve the steerability and stability of the EV. Model parameters can be adjusted, so research on different parameters on the effect of ABS can be carried on, and the simulation model can be used as a well platform for ABS study on EV.

Intelligent Velocity Control Strategy for Electric Vehicles

In conventional vehicles, the control of vehicle speed is achieved by changing the engine load through adjusting the acceleration pedal. However, in electric vehicles, this is achieved by controlling the target motor torque obtained from the look-up table in accordance with the position of acceleration pedal. This method is an open-loop control, with which the engine brake cannot be implemented during downhill trips. In this paper, a closed-loop control of vehicle speed for electric vehicles is proposed. The target vehicle speed is set by the acceleration pedal. The controller collects the real vehicle speed, whereas the PID controller, according to the error of the real and target vehicle speed, adjusts the motor torque in real time to realize the closed-loop speed control. Under such controlling, the motor torque can be changed correspondingly with the resistance, thus makes the driving performance of electric vehicles more identical to that of conventional vehicles.

The Control Strategy of Yaw Moment for Rear Electric Motor Drive Vehicle

With the maturing of in-wheel motor technology, Control on vehicle longitudinal and lateral stability have a rapid development, vehicle with in-wheel motor have also made considerable progress. The paper conducts a study on control strategy of electric vehicle with two in-wheel motors mounted on rear wheels. Yaw moment adopt target following algorithm based on two degrees of model of monorail and study the allocation of torque on two driving wheels. The study indicates that ESP control strategy in which yaw moment of left and right wheel is different and the way of allocating torque based on utilization adhesion can improve vehicle handling ability.

Stability Control of 4WD Electric Vehicle with In-Wheel Motors Based on Integrated Control of Electro-Mechanical Braking System

Each wheel torque can be controlled independently, so four-wheel-drive electric vehicle can not only control the vehicle stability through hydraulic braking pressure regulation, but also through controlling the motor driving and braking force to generate yaw moment, which are different with the conventional vehicles. 4WD Evs have potential applications in control engineering. Both in-wheel motors and the EHB are actuators for vehicle stability control. In this paper, a vehicle co-simulation platform is constructed through the application of AMEsim and Simulink, additionally, a fuzzy controller is designed to generate yaw moment so as to compensate for deviations between CG slip angles and yaw rate. The simulation results show that the stability control system with motors and a mechanical load brake system can effectively improve the handling stability of the vehicle.

Design of Extended-Range Electric Vehicle Integrated Control System Based on Rapid Prototype Technology

Based on Motohawk rapid prototype development platform and “Development to Production (D2P)”development process, an integrated control system has been built, adapting to the principle and configuration of extended-range electric vehicle. This control system integrated traditional vehicle controller, drive motor controller, APU controller, engine controller and generator controller. The development of this control system is based on ControlCore underlying operation system and designed by Simulink/Stateflow software. Production-level automotive ECU has also been used as the hardware platform. This development method can significantly simplify the topology structure of control system, decrease the develop cycle of extended-range electric vehicle, and reduce the cost in development, production and aftermarket maintenance.

Hierarchical Control Algorithm for Stability Enhancement of 4WD Electric Vehicle with In-Wheel Motors

According to the characteristic that each wheel torque of 4WD electric vehicle is independent controllable, the control allocation method with hierarchical structure to optimize the distribution of motor torque can improve the handling stability of the vehicle. The controller is composed of an upper controller and a lower distributor, of which the upper controller can calculate the generalized force of longitudinal force and yaw moment that the vehicle needed based on the vehicle state, and the lower controller is used to figure out the torque allocated to each wheel. The whole vehicle and steering system models are established for simulation and demonstration through the application of Matlab and Simulink. The simulation results show that the control allocation method with hierarchical structure can effectively improve the handling stability of the vehicle.

The Timing Control Research for the Motor in Wheel

For the permanent magnet synchronous motor used in electric vehicle wheel, in order to obtain high torque at low speed, a lot of pole pairs are designed in the structure. So the electrical angle will rotate too fast, and the commutation delay will appear apparently at high speed. The commutation process of permanent magnet synchronous motor is analyzed and the timing control according to rotate speed is deduced. A motor simulation model is built to verify the control strategy. The result shows that the strategy can effectively improve high speed performance of motor.

The Variable PWM Frequency Control Research for the Motor in Wheel

According to the characteristics that the motor in wheel is insensitivity of torque ripple, the impact of reducing PWM frequency on motor control is studied, and the phenomenon that the PWM frequency is limited by the lag angle of motor commutation. Then a variable PWM frequency control strategy according to rotate speed is proposed. Based on Simulink, the motor control model is built and the control strategy is verified by simulation. The result shows that the variable PWM frequency control significantly improves the performance of motor at low speed, with little toque ripple increased.