The steel refinement and its chemical composition and temperature finalization processes in a pouring ladle carried out by heating the metal with electric arc have received wide use at modern metallurgical enterprises. The article considers the electrical operating conditions of the ladle furnace unit (LFU) equipped with a 40 MVA electric furnace transformer. It was expected that the LFU load would vary insignificantly, because the electric arc burns between the electrodes and the surface of already molten metal, without the occurrence of short circuits. However, the accomplished studies testify that the LFU load is abruptly variable and nonlinear in nature, and gives rise to significant voltage fluctuations and harmonic distortions in the power supply network. The flicker intensity (severity) factor has been estimated, and the level of current harmonic components generated due to LFU operation has been determined. By using the obtained results, it becomes possible to predict the influence of LFU electric operating conditions on the levels of electric power quality indicators in changing the power supply network parameters, and to adopt circuit engineering solutions for assuring the electric power quality in the plant electric power supply system.
Improvement of the extra-furnace rail steel processing on the “ladle-furnace” unit in order to increase the operational stability of railway rails
