Software System Design Of Vehicle Controller Unit For Battery Electric Vehicle

With the rapid growth of new energy automobile,a number of new automotive technology came into being.Vehicle control technology of electric vehicle is one of them.Several functional requirements are proposed in the technical standard of a branded battery electric van vehicle controller,including vehicle operation,Controller Area Network(CAN)management,failure diagnosis and protection,and vehicle monitoring.A vehicle control unit(VCU)is designed for the battery electric vehicle(BEV)based on this technical standard.The hardware design of the VCU took the Infineon 16-bit microcontroller XC2268 N as the core of the system.Using multiple switch detection module with serial peripheral interface(SPI),high-side drive module,low-side drive module and standard CAN bus modules to build the system framework.Based on the hardware design,a complete set of software system architecture design and implementation method is proposed in this paper.According to the development pattern and technical specification trends of the industry,V model is taken to offer guidance to development process.The code review is based on the MISRA-C guidelines.The design of network topology and communication protocol for the vehicle system are based on CAN 2.0 protocol.The design of software architecture referred to the AUTOSAR model.On the final version of software design,hierarchical architecture is implemented.Programs of driver layer are invented to provide an application interface with hardware isolation.Process layer calls the driver program to realize the basic operations such as power on self-test,failure diagnosis and protection and safe operation,and finally helps the core layer to realize the control strategy.Finally,the verification of VCU and the ground test are introduced.The software code passed the MISRA-C standard in the static test.And the VCU performed well in the integration test and the function test running on the simulation test platform.The validation of the VCU is proved by ground test.The performance of the whole vehicle is analyzed according to the data of driving record under typical working cycle.