The Control System Research Of In-wheel Motor Driven Pure Electric Vehicle

With the growing shortage of oil resources and environmental pollution, electricvehicles(EV) research and development have become a hotspot in automotive field.Getting rid of the limitations of traditional fuel vehicles, the in-wheel motor driven EVhas a lot of advantages such as high energy efficiency ratio, simplified vehicles’structure, varied driven manners. And the modern EV control technology is a keytechnology to improve the usefulness of EV. So this paper complies with the currentstream of research, provides an specific research on in-wheel motor driven EV controlstrategy and electrical differential control system.First of all, this paper analyzes the research status of EV at home and abroad,studies the in-wheel motor and its control technology which is the core components ofEV. And this paper completes the analysis of the brushless DC motor’s control theoryand method. Base on this, this paper has proposed the electronic differential controlstrategy based on EV’s steering angle and established the electronic differential systemcontrol scheme of in-wheel motor driven EV. Then this paper has analyzed and designedthe in-wheel motor driven EV control system.Secondly in terms of the system hardware, this paper has designed the overallscheme of the double rear in-wheel motor driven EV and illustrates its structure. Thendesigned and manufactured the EV controller including the vehicle control unit basedon TMS320F2812, in-wheel motor drive controller based on PIC18F4580, as well as theCAN communication network between the two units above-mentioned.And then on the system software, this paper has completed the algorithm researchand software implementation based on the proposed electronic differential systemcontrol scheme including the the AD sample of vehicle control unit, electronicdifferential operation, the speed distribution of two driving wheel, in-wheel motorPWM speed adjusting, electronic commutation, in-wheel motor’s current and speeddouble closed loop PID regulation and the specific configuration of nodecommunication in CAN communication network,etc. Finally introduced the concreteimplementation plan of EV prototype, tested the vehicle control system’s hardware anddebugged software on the EV prototype to verify the control performance of the system.