Integrated Structure/Control Design For A Vehicle Electric Power Steering System

Electric power steering (EPS) is a new automotive power steering technology and configuration, which will be used in many fields. Different from conventional hydraulic power steering, The EPS system provides the correct steering assistance by the electric motor. The amount of power to assist is decided according to the speed of vehicle and input steering torque by the electronic control unit. In the process of researching on the EPS system. Firstly, A math model of EPS system is set up after analyzing; Secondly, PD Controller and Fuzzy Neural Net controller are used, a new integrated optimization method to optimize the structure parameters and the control parameters of the EPS system was present. We bring forward two methods during simulation and test. One is the integrated optimization based on Genetic Algorithm for the EPS system structure parameters and PD Control parameters; the other is the integrated optimization based on Genetic Algorithm for the EPS system structure parameters and Fuzzy Neural Net control parameters; Finally, The reduction gear of the EPS system is designed. The result of simulation and test proves that integrated optimization method can improve the portability and sensitiveness of the electric power steering, enhance the automotive controllability and stability.