| 摘要 |
PROBLEM TO BE SOLVED: To ensure an accurate slip correction in vector control by determining a rated torque current from the rated current and the exciting current of an induction motor and the operating the secondary resistance thereof from the rated slip angular frequency, the secondary inductance, the motor exciting current and the rated torque current. SOLUTION: An autotuning means 21 determines a motor exciting current Ids from a no-load current during rated rotation detected by an electric amount detecting means 12, detects a rated slip angle frequency from a rated frequency and a rated speed SB of an induction motor 5 being set by a basic data setting means 20, determines a secondary inductance L2 from a base voltage VB, the rated frequency fB and the no-load current and then determines a rated torque from a rated current Im and a motor exciting current Ids. Subsequently, a secondary resistance R2 of the induction motor 5 is set from the rated slip angle frequency, the secondary inductance L2 , the motor exciting current Ids and the rated torque current. According to the method, accuracy of torque control is enhanced. |
