Lift motor braking system - reverse polarity and uses controlled regenerative braking independent of load

摘要

The system incorporates a reversible-pole alternating-current motor, having a winding with a large number of poles. To stop the lift, motor polarity is reversed, and the cage gently braked to a halt as desired by the occupant, using controlled regenerative braking, independently of the load. To reduce noise, thyristors, connected in anti-parallel, can be incorporated in all three wires to the motor. the design gives gently braking to a halt in the final stages, after creep speed has been reached.