New Speed Control Techniques for High Speed Elevators

The vertical vibration of elevator cars is a serious problem for some high speed elevator systems in tall buildings. To solve this problem an inverter controlled by 32 bits microcomputer has been developed. The system simulates the performance of ideal elevator model and computes the difference between computational speed of the ideal model and the real speed. According to the speed difference, the inverter controls the torque of the induction motor. This system is able to decrease the vertical vibration of the elevator car.