Brushless Motor Steering System Design Based On The SAI Algorithm

As the comfort and security requirement of driving enhances unceasingly, theelectric power steering system (EPS) not only has been widely used, but also therequirement of control performance is proposed further. By studying and analyzingcurrent domestic and foreign research situation and development trend of electric powersteering system, on the basis of design and development of the electric power steeringsystem, the control unit ECU (Electronic Control Unit) of the hardware circuit andrelated Control software is designed, and computer simulation experiment was carriedon the system at the same time, also the reliability and effectiveness of the proposedalgorithm is verified. The main research content of this thesis include: electric powersteering system hardware driver circuit design and increment adaptive algorithm study.First of all, this thesis makes requirements analysis for the electric power steeringsystem. According to the requirements of actual driving, electric power steering systemneed choose different control strategies and control parameters according to thedifferent road condition. Including power sensitivity and return-to-center characteristicsneed to adjust according to different vehicle speed and other vehicle condition.Second, according to the electric power steering system’s reliability and real-timerequirement, designed and developed the drive circuit and drive control algorithm withXC2365as the control core. Implemented the drive control of brushless dc motor,sensor signals and control signals’ acquisition and control. Through the analysis of thehall sensor to get the rotor phase of brushless dc motor, and use XC2365and TLE7183Fcontrol the PMW pulse realized brushless dc motor’s direct torque control, meet therequirement of system control. This thesis completed the design of the control softwarebased on the hardware system and modular design structure, including the mainprogram, motor driver, control algorithm program, etc.Finally, according to the actual application, the mathematical model of the steeringsystem is built for system simulation in this thesis. Through comparing the simulationanalysis results of PID control and incremental adaptive algorithm, the superiority of theincremental adaptive control algorithm is verified.