Power quality measurements and operating characteristics of electric arc furnaces

Abstract

Abstract-Power quality is of increasing concern to utilities and their customer alike. Many loads connected to electric power systems can cause power quality problems at all voltage levels and for very different power ratings due to their unbalanced and non-linear behaviour characteristics.This paper describes the aspects of power quality at the point of common coupling (PCC) where an arc furnace for steel melting with alternating current is connected. By measurements of flicker, harmonics content in voltage and current, active and reactive power and power factor, the preservation of the reference levels for the supply voltage and emission limits for the furnace as a customer are evaluated.The evaluation of the power quality of contemporary International and Argentinian standards is given.The different phases in the operation of the arc furnace are described in detail and illustrated with measurements, and a complete single phase equivalent circuit for the arc furnace is obtained from field tests.

Using the constant current ‒ constant voltage converters to effectively reduce voltage fluctuations in the power supply systems for electric arc furnaces

“…According to experimental data from [15], the value of the short-term dose of the flicker decreases from 4-6 % to 2.5-3 %. In the absence of compensating tools, the quality of electricity, according to experimental research in [16,17], does not meet the requirements. Exceeding the permissible value of the flicker by 10 times, as well as the unacceptable values of a current distortion coefficient, may occur at insufficient power system capacity [18].…”

“…The analysis of experimental diagrams of the current of arc steel-melting furnaces of different capacity [10][11][12][13][14][15][16][17][18] reveals significant stochastic dynamics in the CSS arc current change, especially during the initial melting period. These dynamics possess a certain quasi-periodicity; the boundary modes, idling and operational short circuit, under which there is no release of energy in the furnace, occur quite infrequently, especially three-phase.…”

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

“…The main threats in terms of electricity quality are long-term and short-term voltage fluctuations, the appearance of harmonic current components due to the connection of nonlinear, abruptly changing and asymmetric loads. An example of such a load is an arc steelmaking furnace [1][2][3]. It should also be noted that steel arc furnaces are a source of rapid voltage fluctuations [4,5], which occur due to the asymmetry of currents and voltages.…”

Power Quality Measurement and Analysis in Electric Arc Furnace for Turkish Electricity Transmission System

“…Power quality problems caused by EAFs have been an investigation subject for many researchers. Issouribehere et al have defined single-phase equivalent circuit of EAF plants considering different working conditions of EAFs at boring, melting and refining processes [16]. In addition, Issouribehere et al have examined the relations between the regulations of EAF in Argentina and limit values at power quality [17].…”