| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a controller of AC motors which determines whether they are controllable and automatically adjusts a high-frequency voltage, by automatically, accurately setting position estimate, according to a control mode and a control object used by a user. <P>SOLUTION: The controller includes: a current detector (102) which detects a motor current flowing in an AC motor (101); a parameter identification apparatus (117) which superimposes the high-frequency voltage to a command voltage and identifies inductance, based on the motor current at that time; a position estimate error computing unit (118) which calculates a position estimate error of the A/C motor based on an identified inductance value; an amplitude and frequency of the high-frequency voltage, and a resolution of the current detector; and a position estimate discrimination apparatus (119), which discriminates whether magnetic pole position can be estimated, based on the position estimate error or the identified inductance value. <P>COPYRIGHT: (C)2011,JPO&INPIT |
