| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a control method suitable for an induction motor driving system in which one load shaft is driven by using a plurality of induction motors and a plurality of variable speed controllers that respectively control the induction motor, on the basis of a rotation-angle frequency command value from a higher-order controller. <P>SOLUTION: In a low-speed region of the induction motor 12 from zero speed to a switching value that a rotation-angle frequency detection value ωr inputted to a switching comparator 62 is preset; the variable speed controller 60 executes vector control on the basis of a rotation-angle frequency command value ωr* and a rotation-angle frequency calculation value ωra equal to the rotation-angle frequency detection value ωr. In a speed region of the induction motor 12 in which the rotation-angle frequency detection value ωr exceeds the switching value, the variable speed controller executes vector control, on the basis of the rotation-angle frequency command value ωr* and the rotation-angle frequency calculation value ωra equal to a rotation-angle frequency estimation value ωr#; by having preset hysteresis characteristics imparted to the switching operation, carrying out superior speed control over the entire variable-speed region of the induction motor 12 is carried out, while imbalance in the output torque sharing in each induction motor is suppressed. <P>COPYRIGHT: (C)2008,JPO&INPIT |
