Simulation And Test Of Electric Power Steering System Based On DSPACE

With the application of micro electronic control technology in the automotive field more and more widely,the automobile is developing towards the direction of comfort,intelligence,energy saving and environmental protection.The automobile steering system has also experienced the hydraulic steering,the electronic hydraulic steering,as well as the electronic control steering system represented by active front wheel steering,electric power steering and steer by wire in order to adapt to the development trend of automobile.The electric power steering system is developing rapidly in the electronic control steering system with excellent steering portability and safety in the meantime.Electric power steering system in the field of car steering share continues to improve,and its application begins from the small and medium sized cars to trucks and commercial buses.Electric power steering system needs to be developed and tested by many rounds because of the late domestic research,the dominant position of foreign capital enterprises in the EPS market share and the research of electric power steering technology involving many fields,such as vehicle dynamics,tire dynamics,motor control technology,electronic technology and modern control theory.At present,the domestic EPS system test method is based on the platform and the real vehicle,but this test method has many limitations,such as the insufficient test coverage,the long time test cycle,the high cost,the security threats to the testers and so on.In this paper,the simulation test platform of electric power steering is established by the dSPACE software and hardware system combined with the current research status of the domestic EPS system,the test requirements and the current EPS hardware in the loop test project of a car.By this platform,an accurate,fast and convenient EPS system test is finished which improving the test efficiency,transforming the real vehicle test into an accurate,reliable and analytical simulation process and greatly reducing the dependence on the real vehicle test and the test cycle of the EPS.This paper mainly includes the following aspects:(1)Analyzing the advantages of EPS and the urgent needs of the current domestic research and development and expounding the development trend of the future EPS system,the application status of dSPACE at home and abroad,as well as the important role of V model.(2)Building the simulation test platform of electric power steering system based on dSPACE according to EPS system hardware in loop test requirements,determining the overall architecture of the platform and introducing the dSPACE test platform from two aspects of hardware and software.(3)Determining the design objective of the electric power steering test bench according to the requirements of the test platform and the performance of the EPS system,selecting the appropriate hardware to build the mechanical structure of the test bench and building the simulation model in Simulink to realize the control target of the steering,load and EPS system of the test bed,which lays the foundation for the simulation test.(4)Analyzing the EPS system control strategy and the simulation of the transfer resistance torque in vehicle dynamics model,realizing the virtual vehicle according to the parameters of the target vehicle parameters,analyzing and verifying the correctness of parameterization and developing the computer test management interface to validate the basic function of EPS system.(5)Analyzing the failure mode of the EPS controller,the common fault of the EPS system and the fault safety strategy.