Induction motor control method, control device, iron and non-ferrous equipment, railway vehicle, winder, ship, machine tool, paper machine equipment and transport equipment

摘要

PPROBLEM TO BE SOLVED: To provide a controller and a control method of an induction motor capable of obtaining a high output of a rated output or higher, and to provide an iron manufacture/non-iron facility, rolling stock, a winder, a vessel, a machine tool, a paper machine facility and a conveyance facility in which a power induction motor is controlled by the controller of an induction motor. PSOLUTION: In the control method of an induction motor performing vector control by field-weakening control, when the field flux of the induction motor 1 is in strengthening field flux state; and field-weakening control is performed, when the rotational speed N of the induction motor 1 exceeds a rated rotational speed. At the time of field weakening control, field flux is varied such that the internally induced electromotive force of the induction motor 1 becomes larger than that at the time of rated rotational speed. After starting field-weakening control, field flux is weakened as the rotational speed N is increased, such that the terminal voltage of the induction motor 1 does not exceed the maximum voltage at maximum overload. PCOPYRIGHT: (C)2006,JPO&NCIPI