Research And Implementation Of Hardware-in-the-loop Test System For The VCU Of Pure Electric Vehicle

The double crisis of energy shortages and environmental pollution has led to an increasing number of people thinking about traditional cars,how to improve efficiency and reduce emissions from the automotive industry becomes the focus of attention.Because of high efficiency,zero emissions and other advantages,pure electric vehicles have been pursued by many people and entered a stage of rapid development.Vehicle Control Unit(vehicle control unit,VCU)is the core of pure electric vehicles,carrying dual core functions and security features,so VCU development and testing is particularly important.Hardware-in-the-loop test plays an important role in the development of V-mode that can shorten development cycles and reduce R & D costs.On the basis of the research and analysis of domestic and international system,this paper designs a hardware-in-the-loop test system for VCU of pure electric vehicle based on NI-PXI platform,to achieve the VCU functional testing and strategy validation.The main contents of this paper are:(1)The paper describes the basic structure of pure electric vehicle and the function of VCU.And based on the analysis of the demand and function of hardware-in-the-loop test system,the design scheme of the hardware-in-the-loop is put forward using the hardware and software platform provided by NI-PXI.(2)In order to simulate the vehicle operating environment for VCU in the system test,the forward simulation model of pure electric vehicle is established with MATLAB/Simulink by using modular modeling method based on the theory and a large number of experimental data,including the driver model,the battery model,the motor model,the main reducer model,the vehicle dynamics model and working condition model.Aiming at solving the problem of the poor universality of the system due to the large amount of work done by changing the test object,the vehicle parameter configuration table is designed,which avoids the re-development of the simulation model.The model is converted to a DLL file that can be called directly by Veristand after using the offline-simulation to verify the correctness of the model.(3)In order to improve the scalability of the system,the number of the pins of the boards is more than the VCU test needs in the implementation of the system hardware platform.The hardware and software methods are introduced to make the fault injection test more perfect while designing the fault injection system.And the system information configuration and host computer interface development have completed in the Veristand-based software design process.(4)The paper selects a VCU of the pure electric vehicle as a test object to verify the function of the system.In order to improve the efficiency of the system,the test items and steps are put forward.The system has successfully implemented test on VCU,including power generation logic test,normal driving test,fault injection test and working condition simulation test,and the results of the test show that the system meets the design goal.At present the system has been successfully put into use in a number of vehicle factories.