Realization of Control Algorithm for Electro-Hydraulic Power Steering System Based on MC9S08AW32 Microcontroller

摘要

Electro-hydraulic power steering system (EHPS) can get over the bug of assist power that can't be regulated in the traditional hydraulic power steering system (HPS). Because its assist power is greater than electronic power steering system (EPS), it is suitable for medium and heavy vehicles. In this paper, based on the EHPS system parameters, the control algorithm of the non-linear relations among steering wheel angular velocity, vehicle speed and motor speed of EHPS, which was designed to meet the steering portability at low speed and obvious steering feel and rapid response at high speed and save energy, was given. MC9S08AW32 was applied to design the control system of BLDCM and the scheme of hardware and software were given. The controller communicates with the computer through a special chip. Therefore the digital transmission between the controller and external device is realized. Finally the rationality and validity of the design is verified by the experimental results.