Research On Electric Vehicle Control System Of Asynchronous Motor With Model-Based Design

In recent years,electric vehicles(EV)have made rapid development in the world due to such advantages as no pollution,low noise,simple and reliable structure,high conversion efficiency,Wide source of electrical energy,etc.By 2030,Europe and Japan etc.will no longer produce fuel vehicles,and only produce new energy vehicle,so the development of electric vehicles is a natural trend of globalization.Electric vehicle power from the motor,so the motor and its control system has become the core technology of EV.Development of motor control system is the current research hotspot and has a strong industrial demand.With the rapid development of electronic technology,the previous popular development model by handwriting algorithm code can't meet software development verification and teamwork needs,it is difficult to meet the industry needs has been eliminated.In order to shorten the development period and improve the software safety and reliability,this paper uses Model-Based Design(MBD)to develop the software of AC motor control system.The main work and research results are as follows:?Based on the dynamic mathematical model of AC motor in d-q coordinate system,the FOC algorithm based on rotor field is studied.The causes of voltage coupling are analyzed,and the decoupling method is given.To obtain the maximum torque output in the middle and high-speed stage,the optimal current field weakening control strategy is designed.According to the control characteristics of EV,the torque current and excitation current closed-loop PI regulator is realized.Finally,the realization of SVPWM modulation technology of delta motor is deduced.?The models for FOC algorithm,asynchronous motor and vehicle load are established in the Simulink environment based on the MBD workflow.The system-model by composition of these models is used to simulate the accelerating performance of electric vehicles.?The input and output signals in the simulation model are replaced by DSP peripheral models,and the signal conversion algorithm is established according to the hardware parameters,and the system software model is obtained.The Model Advisor tool verifies that the system software model conforms to automotive software safety standards such as MISRA C: 2010,ISO26262 and MAAB,and finally the model configuration is optimized to generate product-level embedded C code.?In order to verify the validity and reliability of the software code,a voltage source motor controller hardware system is designed according to the actual needs of an electric vehicle.The controller uses TMS320F28069 as the core,including the motor control,car gears,acceleration,brake signal detection,CAN communication and other functions,using low-voltage 72 V lithium battery.?Finally,some experiments are made on the controller hardware and software designed and its software program is verified in this paper,and the experimental results show that the controller hardware and software can meet the functional requirements of electric vehicles on the motor control experiment platform and the test vehicle,and the code generated by system model can run stably and reliably.