Study Of AC Frequency Speed System Of Elevator Controlled By PLC

With the development of the economy, microelectronic technology. computer technology and the automatic theory are developed rapidly, the AC variable frequency technology has been in a new state. It's application is becoming more and more widely. 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technology has developed from DC timing to AC variable frequency timing and it's logic control- relay control also has been replaced by PLC.The article is based on the now-being general frequency converter, using PLC to control the elevator, the reliability is improved and the feeling of comfort is better through the reasonable selection and design, so the effect of control is more ideal.