Electric power steering control device
AssigneeMazda Motor Corporation
InventorMasaki CHIBA
Life of this patent
Estimating the term…
Abstract
There is provided a correcting mechanism (a vibration suppression torque generator, an adder) to correct a motor torque set by an assist map by using a vibration-suppression gain outputted by a filter processor so as to suppress the shimmy. The above-described filter processor includes a vibration extracting filter which has a frequency characteristic that a gain becomes a peak (maximum magnitude) at a cut-off angle frequency and a phase advances by 90° at the cut-off angle frequency and a gain adjustor to vary the cut-off angle frequency of the vibration extracting filter in accordance with a tire rotation frequency which is changeable according to a vehicle speed.
Claims4
An electric power steering control device, comprising:
- a motor to apply an assist torque to a steering device;
- a torque detector to detect a steering torque applied by a driver;
- a setting mechanism to set a motor torque to be outputted to the motor based on the steering torque detected by the torque detector;
- a rotational angle detector to detect a rotational angle of the motor;
- a filter processor to output a vibration-suppression gain for suppressing a vibration due to a tire rotation by performing a filter processing on the rotational angle detected by the rotational angle detector;
- and
- a correcting mechanism to correct the motor torque set by the setting mechanism by using the vibration-suppression gain outputted by the filter processor so as to suppress the vibration due to the tire rotation,
- wherein said filter processor is configured to include a vibration extracting filter which has a frequency characteristic that a gain becomes a specified magnitude at a cut-off angle frequency and a phase advances by 90° at the cut-off angle frequency and to vary said cut-off angle frequency of the vibration extracting filter in accordance with a tire rotation frequency which is changeable according to a vehicle speed.
Dependencies are inferred from the claim text.