| 摘要 |
PURPOSE:To enable to smoothly and rapidly stop by closing a stopping switch when the induced voltage of an induction motor deenergized because of a defect, caused by the remaining magnetism comes to the prescribed value or lower, and applying a brake torque. CONSTITUTION:A stopping switch 14 is provided between a current type inverter 13 which supplies lower variable voltage variable frequency AC voltage than a cycloconverter 3 to an induction motor 5 and the motor 5. The induced voltage due to the remaining magnetism of the motor 5 which is deenergized because of a defect is detected by a voltage detector 19, the switch 14 is closed when the induced voltage comes to the allowable value or lower of a current type inverter 12, and the inverter 13 is controlled by an inverter controller 20 to apply a brake torque to the motor 5. |
