Based On Variable Universe Fuzzy-pid Applied Research In A Vacuum Furnace Temperature Control System

Internal heating distillation vacuum smelting furnace using advanced process technology, with a short process, low energy consumption, little pollution, relatively simple equipments, high metal recovery, is an important equipment for developing new materials and non-ferrous metal smelting, which can be applied to the separation for a variety of binary alloy. Since the seventies of last century, it has been widely and successfully applied in the non-ferrous metallurgical industry. But relatively backward of the refining process control technology,and the low level of automation is always confining the development of vacuum smelting furnace. Therefore,diuscussing how to apply the advanced control theory and technology to the control system of vacuum smelting process in the actual projects will have a very important theoretical and practical significance.According to existing problems in vacuum smelting process temperature control———Nonlinear, big lag, poor accuracy control and difficult to build the mathematical model of controlled object and other issues, this paper applies the idea of "variable discourse of universe ", designs Fuzzy-PID high-precision controller and uses Matlab/Simulink tools for simulation modeling.Through simulation analysis and comparison of Fuzzy-PID control of conventional and new types of Fuzzy-PID control, It's control performance significantly is better than the other one, with fast response, the advantages of almost no overshoot, and also improving the control accuracy of the system.According to process and control requirement, analyzing the vacuum smelting furnace control system's overall structure, we can use advanced control technology to design a set of vacuum smelting furnace monitoring system.On the hardware configuration, the lower computer selects Siemens S7-300PLC, which realizes data acquisition, conversion, on-site electrical equipment control and operation of fuzzy control module and other functions by the programming.Upper computer uses siemens configuration software Wincc V6.0, which can develope smelting process configuration screen to achieve long-range real-time monitoring, parameter setting, alarm indicator and trend display. Finally complete the whole system's hardware configuration, software configuration, the communication of upper and lower computer and program development.After several on-site system debugging, the final commissioning run normally, achieved automatic control of the vacuum smelting process. In terms of the results of theoretical analysis and comparison or the actual commissioning showed that using advanced control theory and control technology in vacuum smelting furnace process can meet the right control requirements of vacuum smelting furnace and the functional requirements of the laboratory assistant and achieved a good control effect.Finally, the paper based on VB.net+SQL 2000 database development platform, combined with Wincc V6.0 configuration software, has developed a vacuum smelting furnace data analysis software synchronously. It also have achieved data import, processing and analysis,Criteria Queries and other functions. The results display in different forms (table or curve), also can be saved, printed or exported to Excel sheet as needed, which is very helpful for data analysis after the experiment.