Apparatus for controlling an A.C. powered elevator

摘要

An apparatus for controlling an A.C. powered elevator is provided to reduce a primary current frequency to an induction motor to be smaller than a specific value when the motor is switched from a power drive to a brake mode of operation. In other words, the frequency after the motor is switched to the brake mode is reduced to be lower than the frequency at which the machine input power to the induction motor is equal to the internal power consumption of the induction motor.