Patent ID: 8775025

Claim:
A steering system wherein a transfer ratio of a steering angle of a steering wheel to a turning, angle of a turning wheel is changed by a variable transfer ratio mechanism, and an auxiliary power is generated during steering by an electric power steering, comprising: a transfer ratio variable motor for changing the transfer ratio, the transfer ratio variable motor being provided in the variable transfer ratio mechanism, and a variable transfer ratio mechanism controlling unit for controlling a rotational angle of the transfer ratio variable motor, wherein the variable transfer ratio mechanism controlling unit calculates a steering angular velocity of the steering wheel, and includes a first correction unit for setting a first correction factor to correct a target current value fed to the transfer ratio variable motor in such a manner that the first correction factor becomes smaller as the steering angular velocity becomes larger, and for correcting the target current value, a second correction unit for setting a second correction factor to correct the target current value fed to the transfer ratio variable motor based on a continuous function which continuously varies from 0 to 1 as an absolute value of the steering angular velocity changes from zero to a first non-zero predetermined value, and for correcting the target current value, the variable transfer ratio mechanism controlling unit is configured to control the transfer ratio variable motor in such a manner that, when the absolute value of the steering angular velocity is equal to or less than the first non-zero predetermined value, a current value flowing through the transfer ratio variable motor gradually comes close to zero.