Modern Elevator Drives for Super-High-Rise and Wide Buildings

Abstract

It is a global trend that buildings are getting taller and wider, that rely on the service of a good vertical transportation system. Conventionally, induction motors driven by VVVF inverters have been the standard drives of elevators. As tall buildings with a height over, say 400 m become popular, the torque-to-size ratio of such induction motors is no longer adequate when the rated speed goes beyond 10 m/s. Permanent magnet synchronous motors become the appropriate candidate. In this article, a review of such application is to be made. Moreover, it is a big wastage of space along the elevator shaft in which only one car is moving. At the same time, as buildings are getting wider and wider, elevators need to move both vertically and horizontally. Both requirements ask for the application of ropeless elevators driven by linear permanent magnet synchronous motors. In this article, a review on the development of such technology in elevator systems is also made. Potential problems with these two types of motors are also highlighted.