Combined Control System for the Coordinates of the Electric Mode in the Electrotechnological Complex “Arc Steel Furnace-Power-Supply Network”

Abstract

To stabilize the electrical mode of an arc steelmaking furnace in the initial stages of melting, it is advisable to use a high-speed current-limiting system, in addition to the traditional electrode movement control system. This system is implemented by including the primary winding of the furnace transformer choke, controlled by thyristors. The use of such a system, on the one hand, reduces the negative impact of the arc steel furnace on the the power supply network operation and, on the other, affects the operation of the electrode movement system, built on the principle of an impedance regulator. In order to analyze the mutual influences between such systems, a mathematical model for the power supply and control system of the arc steelmaking furnace was created. The developed model can work in real time, which corresponds to the world trends of modern control system synthesis for complex technological objects. In the created model, the work of the combined control system with different approaches to the formation of the control effect in the high-speed circuit and the effect of the combined control system on the power supply system of the ASF are analyzed.

Electric Arc Furnace Electrode Movement Control System Based on a Fuzzy Arc Length Identifier

“…The system model presented in [24] was used for the study. The adequacy of this model is confirmed by the coincidence of the obtained results with the results of experimental studies and the results of theoretical calculations obtained by other authors [15,24]. The model uses the representation of the EAF elements (power grid M, furnace transformer TR, electric line with arc SL) in the form of multipoles.…”

“…Today, the technological solutions are provided by such leading companies as Siemens (SIMETAL system), Danieli (HI-REG and Q-REG+ systems), and others. A commonly applicable "standard" strategy for controlling the electrical mode of EAFs is the formation of an "impedance control principle" [3,14,15]. Such a control system is based on phase voltage and current signals.…”

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.…”

“…Wrong movements of electrodes may occur in phases in which the arc length has not changed, and the variation in the current is due to the mutual influence among the phases of the three-phase system [31]. When a high-speed current loop based on an adjustable inductor is used in the system, there is mutual influence between the mentioned loop and the electrode movement control system [32,33]. Stabilization of the current using a high-speed circuit leads to a reduction in the speed of the disturbance response by the electrode movement circuit in the phase where the disturbance occurred, but false electrode movements are reduced in other phases.…”

Electromagnetic and Electromechanical Compatibility Improvement of a Multi-Winding Switch Control-Based Induction Motor—Theoretical Description and Mathematical Modeling

“…A feature of the proposed mathematical model of the switch control-based multi-winding IM is using the method of the average voltages in the integration step (AVIS) [25][26][27]. This method has repeatedly been used by authors, and its high efficiency was demonstrated during a simulation of power schemes with synchronous machines and induction machines, as well as power systems with nonlinearities [26,[28][29][30]. The advantages of the method are high calculation speed and numerical stability, which make it suitable for creating real-time models.…”