基于大电流检测的矿热炉电极升降自动控制系统

Automatic control system for submerged arc furnace electrode lifting based on the large current detection

阐述目前矿热炉采用一次侧电流平衡的控制策略来控制电极升降不足的问题,提出通过罗氏线圈检测二次侧大电流并以此作为控制对象的恒阻抗控制策略,针对该控制策略,设计基于大电流检测的矿热炉电极升降自动控制系统的总体结构,进行系统硬件和软件设计。采用三相综合电量变送器PDM实时采集电炉变压器一次侧电压、电流和二次侧电压等参数,采用罗氏线圈检测系统采集二次侧电流,硬件上采用工控机和西门子S7-300PLC相结合的控制结构,以Visual Basic 6.0为软件开发平台编制了控制系统软件,实现对运行过程的监督和控制,以及数据的实时读取和记录。对于提高矿热炉电极升降控制的准确化、自动化和智能化具有重要的理论意义和应用价值。

This paper describes using Rogowski coil to detect large current on two side of submerged arc furnace and with large current on two side as control object of constant impedance control strategy,which can avoid the weaknesses of using a primary side current balance control strategy to control the electrode lifting. For the control strategy,design overall structure,hardware and software of automatic control system for submerged arc furnace electrode lifting based on the large current detection. With the data for primary side voltage,current and secondary side voltage are real timely collected for the submerged arc furnace transformer by the three-phase integrated electrical quantity transducer PDM,and the secondary side current is collected by Rogowski coil detection system. The control structure of the combination of industrial control computer and SIEMENS S7- 300 PLC is adopted in the hardware,and the control system software is compiled with Visual Basic 6. 0 as the software development platform,to realize the supervision and control of the operation process,as well as the real-time data reading and recording. The study has important theoretical significance and application value to improve the accurate,automation and intelligent of submerged arc furnace electrode lifting control.