ELECTRIC POWER STEERING SYSTEM, AND STEERING ANGLE OUTPUT METHOD

摘要

PROBLEM TO BE SOLVED: To provide an absolute angle detection method that has excellent reliability, in an electric power steering system.SOLUTION: An electric power steering system is configured to comprise: a first rotor 111 coupled to an input shaft 12; a second rotor 112 coupled to an output shaft 14; a torque sensor that has a first angle element 113 measuring an absolute steering angle of the first rotor, and second and third angle elements 114 and 115 measuring a relative steering angle of the second rotor; a reference steering angle determination part 121 that determines a reference steering angle on the basis of the absolute steering angle and the relative steering angle; and a validation part 125 that determines whether or not a difference between a first absolute steering angle and a second absolute steering angle falls within a reference value.