Acrylic Spinning Production Line Control System Design Based On Field Bus

Acrylic synthetic fiber is widely used. Overall demand growth of Acrylic fiber in the world caused by regional economic growth, world population growth and other factors is a good opportunity for developing countries. In our country, more than half acrylic consumptions are from import, the production of domestic acrylic fiber enterprises is still far short of the domestic demand. Therefore, it becomes an important topic related with the development of the national economythe to digest and absorb foreign advanced technology, design advanced acrylic fiber spinning production line control system, improve the competitiveness of acrylic products.Firstly, the paper introduced the background, significance and development of the project. Then based on the introduction of acrylic fiber production process, analysed and summarized the requirements of the control system, and designed the acrylic fiber production line control system network structure and the driving circuit structure. The network structure which takes SIEMENS S7-300 series PLC product CPU317-2DP as the core can be divided into monitoring layer, control layer and field layer. The monitoring layer uses the simple economic MPI bus, and the control layer and the field layer uses the mature and open PROFUBUS-DP bus. This is an economical and reasonable network structure, which can not only meet the real-time requirements of the field control, but also meet the needs of the host computer monitoring. Driving circuit structure also combines the actual:On the one hand,in view of F1 station,it takes beheaded prevention measures for F1 station to guarantee the stability of acrylic concentrate’ generating primary fiber; on the other hand, the other station uses common DC bus technology, the converters are turned to adapt to the DC power supply which can not only maintain the inverter DC side’s voltage stability to ensure the normal operation of the inverters but realize energy saving. Then the paper introduced the control system in detail by the hardware design and the software design. The hardware design begins with a brief introduction to network connection circuit, and then introduces the inverter circuit, rectifier circuit and PLC input and output circuit, finally introduces the configuration of hardware system in detail based on STEP7 programming software.The software design starting from the introduction of communication control of frequency converter respectively introduces the high precision speed control algorithm for stations,loose loop position control algorithm and dancer roller position control algorithm, and emphatically introduces redundancy control strategy for the inverter combining with PLC master-slave communication. Finally, the paper designed the monitoring system based on the WinCC configuration software, and respectively introduced the flow graph,process value file graph and the the alarm graph. It can be seen that the WinCC’s diverse control and flexible scripting programming significantly reduce the development cycle of the monitoring system.After the control system is put into operation, the performance is stable and reliable, and can meet the requirements of the production process.