| 主权项 |
1. An electric power steering device comprising:
a steering mechanism including an input shaft arranged to be rotated in accordance with a steering operation of a steering wheel, an output shaft connected through a torsion bar to the input shaft, and a conversion mechanism configured to convert a rotation of the output shaft to a turning motion of a steering wheel; a first rotation angle sensor provided to the input shaft, and configured to sense or presume a rotation angle of the input shaft, and to output the rotation angle of the input shaft as a first rotation angle signal; a second rotation angle sensor provided to the output shaft, and configured to sense or presume a rotation angle of the output shaft, and to output the rotation angle of the output shaft as a second rotation angle signal; an electric motor arranged to provide a steering assist force to the steering mechanism; and an electric control unit configured to drivingly control the electric motor based on a driving state of a vehicle, the electric control unit including;
a basic assist current calculation section configured to calculate a basic assist current which is a command current to the electric motor, and which is based on a steering torque by a driver,a direction correspondence judgment section configured to judge whether or not a rotation direction of the input shaft and a rotation direction of the output shaft correspond with each other,an advancing phase judgment section configured to judge which of a phase of the first rotation angle signal and a phase of the second rotation angle signal is advanced,a normal/reverse judgment input judgment section configured to judge that a torsion of the torsion bar is generated by a normal input from the input shaft when the direction correspondence judgment section judges the direction correspondence, and when the advancing phase judgment section judges that the phase of the first rotation angle signal is advanced, and to judge that the torsion of the torsion bar is generated by a reverse input from the output shaft when the direction correspondence judgment section judges the direction correspondence, and when the advancing phase judgment section judges that the phase of the second rotation angle signal is advanced,a phase variation judgment section configured to judge whether or not an inversion of a torsion direction of the torsion bar is generated based on the phase of the first rotation angle signal and the phase of the second rotation angle signal, anda disturbance counter current calculation section configured to calculate a disturbance counter current which is greater than the basic assist current when the phase variation judgment section judges that a state where the inversion of the torsion direction of the torsion bar is not generated continues after the normal/reverse input judgment section judges the reverse input. |
