A lift, a vertical transportation system, is used to move people and goods between different floors or levels of a building. The use of motors is essential for the up and down movement of lifts, and in the past, DC motors were often used as the driving device for lifts. For almost the entire 20th century, lifts used AC motors and supplied power to DC motors in a Ward-Leonard system configuration. However, due to the poor torque characteristics of DC motors, they caused severe bumps during acceleration and deceleration, which not only caused a lot of inconvenience to the riders but also increased the wear and tear on the lift. Besides, DC series motors are also not suitable for no-load starting.
With the development of the motor industry, induction motors have gradually entered the market, and the appearance of induction motors has changed many of the problems caused by DC motors in the past. Nowadays, lifts generally use three-phase induction motors with inverter-driven electronic control devices, and some lifts may also use systems with permanent magnet DC motors, and some may use commutator-type DC motors with electronic control. For some lifts with low floors, such as two to three floors, a simple single-phase or three-phase drive hydraulic pump is sufficient.
In general, lifts in the modern world often use three-phase induction motors, but some lifts use other types of motors. If you are wondering which motor you should use, you should consider a combination of the method and reliability of controlling start, speed, torque, and stop, as well as the other features and characteristics of the motor.