Design And Implementation Of Vehicle Control Unit For Light Electric Logistics Truck

As the control center of the electric vehicle,the vehicle control unit(VCU)is responsible for collecting all kinds of switching signals,analog signals,PWM signals and data signals of other electrical components on the communication network of the vehicle.According to these signals,it carries out the execution of the whole vehicle control logic,vehicle fault diagnosis,network management,power management and other functions.After that it sends the processing result to the other electrical components through IO ports and communication network.This thesis designs a vehicle controller,which is used for pure electric light logistics truck to bring out the control of the truck.The main research work is as follows:(1)This thesis analyzes the control logic and required control signals of various electrical components of light electric logistics truck,which can determine the hardware and software function requirements of the vehicle controller.And then the architecture and technical specification of VCU is designed.It also designs the vehicle communication network architecture with the vehicle control unit as the core.On this basis,the transmission type and period of the message are reasonably arranged to ensure the stability and reliability of the communication.(2)After a detailed analysis of the function requirements of the vehicle controller,the hardware circuit is designed,including the minimum system of single chip microcomputer,high/low side drive output circuit,PWM output circuit,communication circuit,internal power supply circuit,analog signals acquisition circuit,input signals acquisition circuit and power supply circuit for external equipment.During the IC selection,circuit design and PCB design,it is taken into condsideration for the performance,safety protection and cost of the circuit,so that the hardware circuit can work well.(3)Design the application software of VCU.Use the method of model-based design to design the application software.Control strategy is the key of application software,which carry out the control mission.A series of processing is performed for the collected signals to ensure that the obtained signals are reliable.At the same time when designing the control logic,the interrelation and restriction among the various systems are considered to ensure the safety,rationality and stability of the control.(4)Carry out simulation test on the model and experimental test of VCU.Control model can be tested and verified in a software environment to ensure that the control logic achieve the purpose.The tested control logic is applied to VCU hardware to perform relevant experimental and real environment test.After these,it is more accurately verified if all the functions of VCU and its system can work normally in actual working conditions.