| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electrically-driven power steering device that holds a light steering feeling by weak field control, and at the same time avoids an event of ineffectual heat generation due to the weak field control becoming invalid, according to the driving state of a motor. <P>SOLUTION: When q axis current Iq, which is torque current corresponding to the driving state of a motor, is set to Iq=Iq', a current vector i will not be set in a dotted area 135 where the rotation number of the motor does not increase but only heat generation increases, but it will be set to a current vector k, by which d axis current Id, which is weak field current, becomes the upper limit value Idlim of a usage area 134 in a usage area 134 indicated by hatching. <P>COPYRIGHT: (C)2013,JPO&INPIT |
