A Mathematical Model of Electrical Arc Furnaces for Analysis of Electrical Mode Parameters and Synthesis of Controlling Influences

Abstract

The synthesis of a real-time model of the electric mode of an arc steelmaking furnace is shown. This model is based on the method of medium-voltage and can be used to analyze the impact of the arc steelmaking furnace on the supply network at different stages of the melting process at different control systems of the electromechanical electrode movement system, and to create model-predictive control systems of electrode movement, when control using hardware in the loop technology. To implement the chosen method, the dynamic arc resistance was used. The last was obtained on the basis of the averaged experimentally taken volt-ampere characteristics of the arc. In paper was proposed its approximation as a current function and arc length. The simulation results obtained using the created model for different operation modes of the arc steelmaking chipboard for a system with a traditional regulator of the electrode movement system are demonstrated.

Increasing the Level of Autonomy of Control of the Electric Arc Furnace by Weakening Interphase Interactions

“…To identify the coefficients of mutual influences between the phases of an electric arc furnace, we use the model of the system described in [32,50]. The adequacy of this model is confirmed in [32,50] based on the coincidence of the obtained results with the results of experimental studies and the results of theoretical calculations obtained by other authors.…”

“…The arc dynamic resistance is a function of the arc current and arc length and is determined based on arc volt-ampere characteristics, for which the following approximation Equations ( 13) and ( 14) were obtained in [50]:…”

“…As an example, in 0, the surfaces of The mathematical models of the elements (power grid, transformer, and electric circuits with an arc) are formed on the basis of Equation ( 12), in which we substitute u arc0 = 0 and R d = 0 for the power grid and transformer, respectively. These models, the model of the electrode movement system with a DC motor, and the calculation algorithm are described in detail in [50].…”

“…During the synthesis of control influences and the investigation of the efficiency of the proposed control systems, the authors applied different models of an EAF [49][50][51]. However, for synthesis of control influences, the system of electrode movement of an EAF is limited to the application of a single-phase model [34,52].…”

Arc Voltage Distortion as a Source of Higher Harmonics Generated by Electric Arc Furnaces

“…The knowledge of the arc model is necessary to determine the optimal operating point of the arc device, i.e., ensuring the maximization of the arc power during scrap melting [1,2]. The stabilization of the operating point is achieved through the use of electrode shift control systems, which use algorithms dependent on the adopted arc model [3,4].…”