US 12,473,018 B2
Electric power steering device
Hideki Sawada, Tokyo (JP); Hidetaka Koinuma, Tokyo (JP); and Takayoshi Sugawara, Tokyo (JP)
Assigned to NSK STEERING & CONTROL, INC., Tokyo (JP)
Appl. No. 19/111,115
Filed by NSK STEERING & CONTROL, INC., Tokyo (JP)
PCT Filed May 10, 2024, PCT No. PCT/JP2024/017490
§ 371(c)(1), (2) Date Mar. 12, 2025,
PCT Pub. No. WO2024/241922, PCT Pub. Date Nov. 28, 2024.
Claims priority of application No. 2023-082835 (JP), filed on May 19, 2023.
Prior Publication US 2025/0263113 A1, Aug. 21, 2025
Int. Cl. B62D 5/04 (2006.01)
CPC B62D 5/0463 (2013.01) [B62D 5/0409 (2013.01)] 10 Claims
OG exemplary drawing
 
1. An electric power steering device comprising:
a motor configured to generate a steering assist force to be provided to a steering system of a vehicle;
a current command value calculation unit configured to calculate a current command value to control driving current of the motor;
a current control unit configured to output a first voltage command value, based on current deviation of a measured value of driving current of the motor with respect to the current command value;
a first gain setting unit configured to set a first gain depending on rotational velocity of the motor;
a disturbance voltage suppression unit configured to calculate a third voltage command value by adding output from a first delay element to a second voltage command value obtained by limiting the first voltage command value by the first gain and also input the third voltage command value to the first delay element; and
a driving circuit configured to drive the motor, based on the third voltage command value.