ELECTRIC POWER STEERING SYSTEM AND A CONTROL METHOD THEREOF, CAPABLE OF SUPPLYING TORQUE COMPENSATION WITH A DOUBLE BOOSTER CURVE BY OVERLAYING COMPENSATION TORQUE ACCORDING TO INCLINATION AND STEERING FORCE TORQUE ACCORDING TO INPUT OF A DRIVER

摘要

PURPOSE: An electric power steering system and a control method thereof are provided to supply maximized torque compensation without foreign body sensation by overlaying two booster curves and controlling the compensation torque when the compensation torque is applied.;CONSTITUTION: Compensation torque for supplying a steering force is determined by applying vehicle speeds, steering torque, and steering angles to a map. The inclination due to a lateral force is determined by analyzing the steering torque and yaw rate. When the inclination due to the lateral force is determined, inclination prevention compensation torque is determined by applying the inclination to a predetermined torque compensation map. A booster curve is determined on the inclination prevention compensation torque. A motor is driven by two booster curves in order to perform torque compensation by overlaying the determined compensation torque and the predetermined booster curve.;COPYRIGHT KIPO 2013;[Reference numerals] (AA) Start; (BB) No; (CC) Yes; (DD) End; (S101) In driving; (S102) Detect vehicle speeds, steering angles, and steering torque; (S103) Determine assist torque; (S104) Yaw angle CAN signal detected?; (S105) Drive an MDPS motor with the assist torque; (S106) Determine the occurrence of inclination; (S107) Determine compensation torque; (S108) Determine a boost curve; (S109) Overlay driver input compensation torque and inclination prevention compensation torque; (S110) Drive the MDPS motor