CONTROL DEVICE OF INDUCTION MOTOR

摘要

An object of the invention is to provide a control device of an induction motor where an inverter circuit can be protected from overcurrent by stable current limitation operation not only at steady operation but also at rapid acceleration/deceleration or at regenerative braking. A current component calculation circuit calculates a first current component from primary current detected by a current detector and output frequency. A correction frequency calculation circuit calculates a frequency correction value using a current limit value and the first current component according to prescribed function calculation. A subtractor subtracts the frequency correction value from a primary frequency command value. A voltage component calculation circuit calculates a primary voltage component command value according to the subtracted output. A primary voltage command calculation circuit calculates a primary voltage command value of the induction motor from the subtracted output and the primary voltage component command value and outputs it to a voltage conversion circuit.