What are the main electrical control systems of elevators?

The development process of elevator electrical control system can be divided into four stages:

The first stage is represented by relay control, which is characterized by many fault points, complex logic circuit, poor reliability, large number and volume of components and difficult maintenance.

The second stage is represented by AC voltage regulation and speed regulation technology. The main outstanding problems are: the circuit is quite complex, the debugging is cumbersome, the leveling error is large, the daily maintenance workload is large, and it is easily affected by environmental changes.

The third control system is represented by PLC or microcomputer board, plus general frequency converter or elevator special frequency converter. Although this system has good overall performance and high reliability, it occupies a large space, has relatively many possible fault points, makes insufficient use of resources and is inconvenient to maintain. At present, relay control and AC voltage regulation and speed regulation control are hardly used in elevators, and PLC control in passenger elevators is rare. There are some PLC controls in freight elevators, escalators and sundry elevators.

The fourth stage is to integrate the logic control part and the motor drive part to form an integrated elevator control system, which leads the market and technical trend with its remarkable cost performance, saves a lot of debugging, maintenance and maintenance time, greatly reduces the cost, and has the advantages of convenience, simplicity, good stability and energy saving. With the rapid development of modern science and technology, elevator integrated control technology has gradually matured and become the mainstream.