Elevator Control System By PLC

With scientific and technological and socio-economic development, high-rise buildings have become the hallmark of modern cities. As a vertical lift equipment, a lot of people bear the transportation and logistics, its role in building essential. At the same time, it has to lift the performance requirements are also increasing, such as reliability, easy to operate, comfortable nature, low noise, consumption, and so on. But the elevator as an important traffic in skyscraper,it also has developed quickly with the improving requirement of the People .It's dragging technology has developed from DC timing to AC variable frequency timing and It's logic control-relay control also has been replaced by PLC. using PLC to control the elevator,the reliability is improved and the feeling of comfort 15 better through the reasonable selection and design,so the effect of control is more ideal. In order to meet the comfort, improve transporting efficiency and reach the right floor, the given curve of an elevator is a key point. Most of people's sensitivity on changing speed is about acceleration movement. Comfort means acceleration and deceleration on smoothness. To acquire favorable comfort, the starting and braking curves design of the elevator is composed of two s-curves and one beeline. Through adjusting the acceleration time and that of the s-curve's, ideal starting and braking curves are gained.This paper, based on the introduction of the elevator's basic structure, expatiates the drive and control principle of elevator, and analyzes how to use the PLC to program controlling process. The implementation project of elevator's VVVF control system based on PLC and transducer is studied and proposed. This article was precisely has carried on the improvement design in view of these questions to the existing elevator system. Uses PLC to carry on the logical control, modulates velocity the elevator control system with the frequency changer.