| 摘要 |
<P>PROBLEM TO BE SOLVED: To overcome the problem that, by vector control that converts a conventional three-phase motor to a d-q axis, a variation in the motor parameter of a part of a phase caused by heat generation exerts influences upon all phases for d-q axis conversion, whereby the variation cannot be controlled so as to be completely corrected, a motor torque ripple is generated, and steering operation with a good feeling has not been achieved in an electric power steering device. <P>SOLUTION: A current command value calculated from a torque command value obtained by steering operation is set to be a current command value at each phase, the current detection of a motor is also performed at each phase, and current control that makes the current command value of each phase and the detected current value as inputs is also performed at each phase independently, whereby the variation in the motor parameter generated at a part of the phase does not exert an influence upon the other phase. Since the control for correcting the variation by executing closing with a control system for only the phase is made possible, the generation of the torque ripple is suppressed. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
