The Development Of Automatic Feeding Process Control System For Magnesium Smelting

Liaoning accounted for20%of the world’s magnesite reserves, ranking first in the world. Fused magnesia can be obtained from raw materials through melting with arc furnace. It is a very important step to transport the ore to the arc furnace in the smelting process. In response to the problem that shabby feeding equipments in a low level of automation are still being used in most domestic fused magnesia enterprises and through the analysis of the mechanical structure of the feeding system, a new kind of automatic feeding process control system for magnesium smelting based on PLC, inverter and touch-screen is developed in this paper.Based on the mechanical structure, an automatic feeding process control system with a touch-screen is constructed in this paper using PLC, inverter and configuration software. The design and the assembly of the electrical part are described in detail in this paper, so is the site commissioning mechatronics. Last but not least, some diagrams are listed such as the mechanical structure diagram, electrical wiring diagram, components mounting hole location map in the control cabinet, sequential functional chart for process control and the ladder program for PLC. During the process of mechatronics commissioning, a solution that using inverter to drive the three-phase motors is proposed in response to the problem that the operation speed of the feeding mechanical is too fast. And the problem that the overvoltage across the inverter during constant operation is solved by adding consumption brake components after analyzing its reason and hazard.During the creation of touch-screen control interface for the automatic feeding system, the author uses the characteristics of Windows CE platform to add a function that stores the historic operation data in USB disk. The operation effect shows that the historic data can not only be displayed on the touch-screen, but also read with Excel in the desktop and laptop, which is convenient for the statistics and management.The feeding system developed in this paper has already been made in the Yingkou Dongji Science and Technology Corporation’s workshop, and will be put into trial operation. As part of the National863Plan’Energy Conservation Technology and Equipment for Efficient Preparation of Fused Magnesia from Low-grade Magnesite’, it provides a practical solution for the automated upgrade of feeding operation in fused magnesium smelting plant and a strong technical support for the system integration on the future smelting production line to realize automated monitoring, diagnostics and control throughout smelting process.