A Research On The Electronic Control System For Electric Car

With the fuel car retains the quantity increases ceaselessly, the current worldenvironment worsens day by day, the development of oil resources excessive use, hasgradually in short supply, development and protection of environment, the use of oilaccident as the driving force of the vehicle will be on the agenda, so no pollution forelectric automobiles has received more and more attention by the various regions ofthe world, the pure electric replacing fuel automobile is also the inevitable trend of thedevelopment of automobile industry. In this article has been put into operation inenterprises listing abroad pure electric vehicle based on the vehicle, to control systemas the research object, the pure electric car electronic control system hardware andsoftware for the overall design, optimization, and through the real vehicle test to provethat its work reliability.This paper first describes the current domestic and international developmenttrend of electric vehicles and current situation, choice of permanent magnetsynchronous motor as the driving motor of electric vehicle. Subsequent analysis of thepermanent magnetic synchronous motor structure, performance characteristics,combined with the coordinates transform established the mathematical model ofpermanent magnet synchronous motor. On the voltage space vector pulse widthmodulation (SVPWM) made the theory, the method of permanent magnetsynchronous motor vector control strategy.In the motor control system hardware, with the national standard,the controlsystem of standard specifications, the choice of components, circuit board design,interface definition, standard wiring to the standard control and protection function,start, stop process, standard calibration and man-machine interface parameter settingsare defined, and the control mode, working condition judgement and switchingprocess, driving torque distribution strategy, braking torque distribution strategy, faultprocessing mechanism are discussed.In the software design process, the whole software by a series of standardstructure software function module, the software module is divided into three levels:management, execution layer and interface layer. The vehicle controller through CANbus network, to complete the motor drive control, braking energy feedback optimalcontrol, vehicle energy optimal management, network management, fault diagnosis and protection, vehicle condition monitoring and other functions. On vehicleoperating switching process, driving torque is given, motor overload, regenerativebraking, control strategy of main flowchart of the software are described.By the end of the prototype were some functional test, correlation function andthe measured indexes have reached the design requirements.