The Motor Current Sensor Fail-Operation Algorithms for the EPS System

Recently, as the autonomous driving technology has been actively developed, the safety performance of EPS(Electric Power Steering) system of automobile is increasing more and more. Therefore, this paper propose a current sensorless control method that can continuously control the motor current even when the current sensor used for motor control in the EPS system fails. The current sensorless method proposed in this paper is a structure that preliminarily measures the output voltage required for motor current control and saves it as a table in SW, and it can be implemented easily without modeling of motor or parameter estimation The proposed method is implemented in EPS system of real vehicle and its performance is verified to be sufficient for steering assist.