US 12,344,328 B2
Electric power steering system
Takanori Tatebe, Tokyo (JP); Naoto Yabuki, Tokyo (JP); Kazuki Furukawa, Tokyo (JP); and Takahiro Inami, Tokyo (JP)
Assigned to SUBARU CORPORATION, Tokyo (JP)
Filed by SUBARU CORPORATION, Tokyo (JP)
Filed on Jan. 23, 2023, as Appl. No. 18/100,186.
Claims priority of application No. 2022-014206 (JP), filed on Feb. 1, 2022.
Prior Publication US 2023/0242177 A1, Aug. 3, 2023
Int. Cl. B62D 5/04 (2006.01)
CPC B62D 5/0463 (2013.01) 16 Claims
OG exemplary drawing
 
1. An electric power steering system comprising:
an electric actuator configured to apply assist force to a steering device, the steering device being configured to turn a steering wheel of a vehicle;
at least one processor; and
at least one machine readable non-transitory tangible medium storing instructions that are configured to cause the at least one processor to:
generate a current indication value in accordance with a target value of the assist force;
supply electric power to the electric actuator in accordance with the current indication value; and
add a noise signal to the current indication value, the noise signal having a dominant frequency that is a frequency matching a control clock frequency of the vehicle or a harmonic component of the control clock frequency, wherein
an amplitude of the noise signal is increased in accordance with an increase in a traveling speed of the vehicle, and
the amplitude of the noise signal is decreased in accordance with an increase in torque amplitude of the steering device.