| 摘要 |
A q-axis target current setting unit generates a q-axis current command value based on a steering input signal from a steering torque sensor and a vehicle speed signal from a vehicle speed sensor. An electric motor generates a predetermined torque based on the q-axis current command value and a q-axis current (a torque current) to which a fed back q-axis real current is added. On the other hand, a d-axis correction current setting unit sets a field weakening current (a d-axis current) in response to a voltage saturation (duty ratio=driving voltage of electric motor/power supply voltage) output from a voltage saturation calculating unit. For this reason, when the voltage saturation becomes high, distortion (harmonics component) in current can be decreased by decreasing the voltage saturation while keeping the torque constant using a predetermined torque current, and a torque ripple can be suppressed.
|
