Nosov Magnitogorsk State Technical University, Magnitogorsk, Russia:

A. A. Nikolaev, Cand. Eng., Associate Prof., Head of the Dept. of Automatic Electric Drive and mechatronics, e-mail: aa.nikolaev@magtu.ru
P. G. Tulupov, Cand. Eng., Junior Researcher, Dept. of Automatic Electric Drive and mechatronics, e-mail: tulupov.pg@mail.ru
S. S. Ryzhevol, Postgraduate Student, Dept. of Automatic Electric Drive and mechatronics, e-mail: snaffls18@gmail.com

The control algorithm for combined ceramic regenerative burners (Regenerative Ceramic Burner, RCB) and carbon-containing material injectors of a flexible modular arc steel-smelting furnace DSP-1 operating at one of the domestic metallurgical enterprises is considered. It was revealed that in the concept adopted in production, the decision to switch the RCB burner from the burner mode to the oxygen lance mode, as well as to turn on the carbon-containing material injectors, is made directly by the operator of the furnace plant based on a set of empirical features characteristic of one or another technological stage of melting. In this regard, an improved control algorithm for RCB burners and carbon-containing material injectors has been developed and proposed for implementation, which will ensure the adoption of the above-mentioned decisions in automatic mode. This algorithm is based on the analysis of the slag coefficient, the value of which directly depends on the level of higher harmonics in the spectrum of electric arc current signals, as well as physical processes occurring inside the furnace bath. The implementation of the proposed algorithm enables to achieve the most timely adaptation of operating modes of combined burners and carbon-containing material injectors, which in turn will increase the overall energy efficiency of the steelmaking complex as a result of an increase in the total thermal efficiency of electric arcs and the optimal operating mode of the burners.
This work was supported financially by the Ministry of Science and Higher Education of the Russian Federation (Project No. FZRU-2020-0011).

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