| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a control method and a control unit of an AC motor, with which an offset amount of a current can precisely be detected in accordance with an operation situation of the AC motor and which can perform highly precise control without errors when an operation command value changes and in a halfway transient state where revolution speed changes. <P>SOLUTION: The control method of the AC motor having a current sensor and a position sensor includes: period detection steps (S2 and S5) detecting one period of an electrical angle; a current detection step (S1) detecting an instantaneous value of the current for one period; a current addition step (S4) adding the instantaneous value of the current and allowing it to be an offset detection value; a determination step (S7) determining whether an operation situation of the AC motor changes or not in one period; an updating step (S9) updating the offset amount based on the offset detection value when the operation situation of the AC motor is stabilized; and an abolition step (S8) abolishing the offset detection value when the operation situation changes. <P>COPYRIGHT: (C)2013,JPO&INPIT |
