| 摘要 |
PURPOSE:To perform smooth start regardless of whether an induction motor is driven from the hoisting machine side or not after the release of a brake. CONSTITUTION:An elevator system is provided with a hoisting machine 8 for driving a car 7, an induction motor 3 for driving the hoisting machine 8, a brake 6 for braking the hoisting machine 8, and a pulse signal generator 4 direct-coupled to an inverter device 2 and the induction motor 3. In such an elevator system, the inverter is started before the release of the brake 6 to make the induction motor 3 only excited, and then if the induction motor 3 is at a stop without being driven from the hoisting machine 8 side after the release of the brake 6, only the exciting action of the induction motor 3 is performed. In the case of the induction motor 3 being driven from the hoisting machine 8 side and rotated, normal operation is started after zero speed control. |
