Developing the method of optimal settings of a nonlinear impedance controller of arc steel melting furnace

The paper proposes the methodology for choosing the optimal coefficients of a nonlinear impedance controller as part of the control system for the electric mode of an electric arc furnace (ESF). The focus of the study was an arc steel-smelting furnace of shaft type ShP-125 (85 MVA) with an ARCOS electric mode control system and a nonlinear PI impedance controller. The paper considers in detail the stages of practical application of the proposed methodology. It describes a mathematical model of the ARCOS control system with a non-linear PI impedance controller. The model was used to evaluate the current control system settings and conclude that it needs to be optimized. The developed methodology allowed for determining the new values of the coefficients of the nonlinear PI controller. They ensure the operation of the impedance control loop which is close to the technical optimum. The paper presents the results of applying the improved parameters of the ARCOS control system and the calculation of the technical effect. The scientifically based conclusions prove the effectiveness of the proposed approaches.