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This article proposes a new adaptive commissioning methodology for arc flash mitigation in steel manufacturer users considering the Tap-to-Tap varying current consumption. This process is achieved through adaptative protection settings computed to reduce the total clearing time of relays adding the restriction of the incident energy. The proposed methodology carries out the detection of abrupt changes in current consumption to detect Tap-to-Tap change in operation stages of electric arc furnaces. The application of this methodology is performed on a steel manufacturer user and shows the reduction of the incident energy values according to Tap-to-Tap operation cycle. [ABSTRACT FROM AUTHOR]

This article proposes a new adaptive protection setting methodology for steel manufacturers, aiming to reduce miscoordination between main feeders and current consumptions due to fault clearance or high load disconnection. By detecting abrupt changes in current consumption, the computation of different protection settings may be achieved. The application of this methodology is performed through the assessment of a steel manufacturer who sustained an arc blast of one of their protection cells, and a description of the way in which the proposal permits avoidance of such catastrophic conditions. [ABSTRACT FROM AUTHOR]

The use of a unified power flow controller (UPFC) to improve the power transfer in an EAF is investigated. The implemented equipment used techniques of hardware-in-the-loop to determine the required specific characteristics of the UPFC to improve the stability of the arc. The arc is mainly responsible for the conversion of electromagnetic power into thermal power and heat transfer. The stability studies of power networks help in improving the stability of the arc. These are the topics covered in this paper. This research also shows how it is possible to achieve an increment of the stability of the arc with the enhancement of the power quality between the main transformer and the distribution system through the decrease of the THDI, unbalance, and flicker. [ABSTRACT FROM AUTHOR]

The objective of this paper is to analyze the decrease of the “tap to tap,” or operating time, of arc furnaces. A study that includes dynamic programming is carried out in the programming of operation of electric arc furnaces. Optimization of the operation is performed at a later phase of the research. Each step of the process is analyzed or put into operation following the direction of an expert. Following specific operating conditions, the behavior of the furnace is characterized and the relationship between voltage levels in the secondary arc is identified using a circular diagram in order to find the feasible region for the optimal solution. The search is carried out in the furnace feeder, and the furnace specific mechanisms are identified in order to decrease the “tap to tap.” This analysis allows the proposal of a new optimization model that considers dynamic. [ABSTRACT FROM AUTHOR]

Transient behavior in grounding systems related to electric arc furnaces (EAF) might be studied using an approach to Kron’s circuit model to solve Maxwell’s differential equations in electromagnetic field theory. This paper presents a circuit model designed using Kron’s approach implemented in alternative transient program (ATP). The model is suitable to describe accurately the behavior of real complex grounding systems dealing with continuous operation of an EAF. Some ideas about the behavior of the power quality are evaluated by simulation of the grounding system in ATP. [ABSTRACT FROM AUTHOR]

This paper presents a new technique to characterize electrical arc furnaces through the measurement of electric power, stationary and transient states, and the imbalance of these systems. The nonstationary behavior of the voltage and current signals in electric arc furnaces is considered, and analysis techniques of power quality in the time domain are used. ATPDraw (Electromagnetic Transient Program) was used to validate the characterization of the electric arc furnace, and the simulation results were compared with the measurements taken in a local steel manufacturing facility. [ABSTRACT FROM PUBLISHER]