Variable Frequency Speed Regulation Of Gearless Asynchronous Traction Machine Based On Vector Control

As the elevator drive equipment, Traction machine has developed more than a century The development has experienced through the DC drive, AC drive, gear and gearless, due to the different needs of the elevator's speed, capacity etc. As a kind of gearing machine, the drive host of the elevator has always been required more stringently. Firstly, the lifting of the elevator is absolute position control. So it requires that the closed loop control of position reaches a certain accuracy. Secondly, the safety and comfort of the elevator contact directly with the performance of the traction machine. So these features, low noise, low vibration, low power cost, are needed in designing. And this is right the reason why gearless traction machine has become the domination of the market.This paper begins with the basic principle of vector control of induction motor. And develops the gearless asynchronous traction machine variable frequency control system, based on the existing gearless permanent magnet synchronous traction machine. Compared with permanent magnet motor, the induction motor has a more complicated decoupling algorithm which is the focus of the paper. The hardware cores of this control system include digital signal processing TMS320F2812of TI and intelligent power module of Mitsubishi. The other components, such as encoder, switching power supply and protection circuit, will be discussed in the body.The last section of the paper presents the performance analysis, such as power factor, efficiency and load capacity, of the gearless asynchronous traction machine. And gives the converted velocity curve of elevator in using this system for speed and position closed-loop control. It can be seen from the results that, the performance and control accuracy of gearless asynchronous traction machine can achieve a comparable degree with the permanent magnet synchronous motor. Taking into account of the rare earth resources and the cost of business, we can see a bright future of the gearless asynchronous traction machine and its control system.