Research On Control Strategy And Control Method Of Ferromanganese Alloy Refining Furnace

Ferromanganese alloy is a kind of ferroalloys and is an important deoxidizing agent and additive in iron and steel smelting,and it plays a strategic role in the process of construction production.At present,at most ferromanganese alloy production enterprises in our country,the production level and the application of advanced control technology are relatively backward.Many enterprises still use manual control and semi-manual control.Therefore,realizing automatic control in whole entire process ferromanganese alloy smelting is pretty significant for promoting product quality and improving production efficiency.Backed by the design of an automatic control system of a large ferromanganese alloy refining furnace at a ferroalloy factory,this thesis designs the automatic control system of refining furnace ferromanganese alloy electrode for achieving the ferromanganese alloy smelting production process automatic control,improving the production efficiency,and strengthening the smelting efficiency.The submerging arc technology is used in the ferromanganese alloy refining furnace when producing,and burden is gradually added in the furnace as smelting alloy.Due to the requirements to control the electrode is different between the different periods of smelting,it is necessary to employ the control strategies and the control methods to realize control section.Through analyzing the refining furnace production process and the characteristics of the furnace circuit,this thesis summarizes the characteristics of the smelting process and the control requirements.based on a system controller design,Based on the characteristics of control strategy and control methods,and combined with the expert experience knowledge accumulated in the actual production process,the scheme of electrode controllers in different smelting stages of the furnace condition based on automatic identification is designed.Furthermore,depending on the Siemens company's S7-300 PLC platform,this thesis realizes the practical ferromanganese alloy refining automatic control system,verifies the effectiveness of title controller,realizes the automatic control during the whole process of smelting,and raises the efficiency of ferromanganese alloy production.In the process of automatic control system design,the main work contains the following aspects:(1)This thesis achieves the design of the furnace condition automatic identification and the controller based on expert rules.a?based on the characteristics of the smelting ferromanganese alloy production process,the melting process is divided into the arc smelting and the reduction smelting stage.By using fuzzy expert system,the standard deviation of electrode current,the power input and the melting time are used as the inputs,this thesis implements the automatic identification of normal smelting furnace condition.b?by employing the traditional expert system and the change of electrode current,the refining furnace automatic identification of abnormal furnace condition is realized.c?according to the expert experience in actual production and the analysis of the furnace circuit,this article summarizes the expert control rules and implements the automatic control of the system during the arc melting phase.(2)This thesis achieves the design of fuzzy PID controller of the electrode system based on the constant impedance control strategy.In the smelting reduction of the ferromanganese alloy,the constant impedance control strategy is used.The PID parameters is tuned online by the fuzzy controller,and the control system of the electrode is realized.(3)The industrial application system design is realized in this thesis.The automatic control system using the PLC and industrial computer as the platform is designed,which has the functions of data acquisition and processing,controlling production process,operating platform,and data communications and monitoring.