Research On Distributed Hardware-in-the-loop Test System For Electric Vehicle

With the continuous advancement of the "new four modernizations" of automobiles,electric vehicle have gradually entered the public’s field of vision.The core electronic control unit of a electric vehicle includes a vehicle control unit(VCU),a motor control unit(MCU)and a battery management system(BMS).Generally,the V-mode electronic control system development process is adopted for development,and hardware-in-the-loop testing is used.Verify its own control strategy.When verifying the performance of coordinated control after matching the VCU,MCU,and BMS,the joint debugging method based on bench or real vehicle is often used,which has disadvantages such as difficulty,high cost,and long cycle.The joint hardware-in-the-loop test of multiple ECUs was carried out in the early stage of research and development,which provided a new solution for the verification and optimization of the collaborative control strategy of VCU,MCU and BMS.This thesis analyzes the limitations of traditional hardware-in-the-loop test systems in the joint test of multiple ECUs,and combines distributed simulation technology to design and build a distributed hardware-in-the-loop test system for pure electric vehicles.The specific research content is as follows:(1)Research on the high-level architecture(HLA)of building a distributed simulation system,analyze the importance of real-time data transmission between models in distributed simulation,and adopt the scheme of building a reflective memory network to meet real-time requirements.The conditions for synchronization of distributed simulation are clarified,which provides a theoretical basis for realizing system synchronization simulation.(2)Analyze the composition of the system,and propose an overall design plan for the distributed system based on CAN bus,local area network and reflective memory network according to the function and performance requirements of the system.Through the functional analysis of the tested ECU,combined with the functional requirements of the HIL node,the general scheme design of the HIL node is completed.(3)Using modular modeling ideas,combined with the analysis of the powertrain structure of pure electric vehicles,based on MATLAB/Simulink,a forward simulation model of the vehicle for distributed hardware-in-the-loop test systems is established,which mainly includes working conditions and drivers,Reducer,motor,battery and other modules.According to the characteristics of distributed parallel simulation,the model division and processing methods are studied to improve the simulation efficiency of the model after division.(4)Based on the hardware resources of the NI-PXI platform,the hardware selection is carried out in combination with the signal types required by the ECU,and the HIL nodes for different tested ECUs are built.Use NI-PXI distributed system management software and compiled models to build a software environment,and then realize the system’s software and hardware integration,and develop practical and beautiful HMI man-machine interface.(5)Establish a joint test project,optimize the triggering mode of the model,complete synchronization between system nodes,and design a test plan to perform functional and performance tests on the system.Comprehensive analysis of the test data files has initially verified the effectiveness of the system.