Design And Research On The Computer Processing Control System In The Cement Rotary Kiln

With the development of the Chinese cement manufacturing, The cement rotary kiln has been developed very soon. In order to realize the monitor and control of important manufacturing parameters during the tread preheating, precalcining, calcining, chamotte's cooling, the preparation and the transportation of the powdered coal, waste gas processing, a computer supervisory system based on Profibus-DP is developed.Considering the real needs of the project, a IPC&PLC&field-bus structure is adopted to solve the control problems, such as the complexity of the manufacturing flow, multiplicity of equipments, excessiveness and disperse of I/O and high demand of avoiding blast.The net structure of the cement rotary kiln control system has three layers. The locale Layer is composed of several subordinate stations. In each station, the PLC with PROFIBUS interface is selected to control the locale equipments and collect the locale data. The second layer connects one data server to one main station by PROFIBUS.The data server manages the database of the whole net, and accomplishes the router between Ethernet and PROFIBUS. S7315-2DP, as the main station is used to harmonize the work among these DP slaves via fieldbus communication;The management layer, using IPCs as the operational stations to display parameters, deal with alarm information, print report forms and so on to realize the remote monitor and control. The whole system is not only embodied the distributed control, centralized management of distributed control system, but also incarnate the characteristics such as total digital communication, highly openness and reciprocation of field-bus control system.The production process of the cement rotary kiln is a typical engineering thermodynamics with great inertia, pure lag and strong coupling. So traditional control can hardly control it accurately. In order to guarantee the process stable, produces the high-grade cement clinker, it is important to make the temperature of the calcination strip and the waste gas of kiln tail stable. This article has studied the fuzzy control theory and design way of fuzzy controller, used fuzzy control to optimize the control, researched the parameters of producing process in detail, brought forward subjection function and fuzzy control rules list of cement kiln input and output parameters and designed fuzzy control imitation software by fuzzy control toolbox of MATLAB. Applied the software to cement kiln imitating process, it has better control effect and definite significance in comparison with the basic PID control simulation structure.The simulation result indicated that the fuzzy control could satisfy cement rotary kiln well.