STUDY OF THE CURRENT IN THE MULTIELECTRODE PLANT BATH

Abstract

Active resistance heating multi-electrode ore-thermal furnaces, being in quasi-stationary and transient modes, work in the conditions of electric loop dissymmetry formed by the furnace transformers, current supply and bath caused by the action of different factors of geometric, electromagnetic, thermal and technological character. They worsen the energetic, technological and operational performances. The present methods of studying the electric processes in the furnace loop do not allow in full measure to reveal, consider and eliminate factor actions resulting in phenomena causing electrical duty dissymmetry. Unbalance of the system of currents flowing from the electrode to electrode passing the melt and unbalance of the system of currents flowing directly onto the melt influence the dissymmetry of the furnace loop electrical duty. The work objective is forming the calculated formulas for determining the resistance heating three-electrode furnace bath “star” and “triangle” currents and by means of them studying the electrode and bath geometrical parameters influence on the mentioned currents. Materials and methods. The study object is currents flowing in the resistance heating three-phase, three-electrode furnace bath. When carrying out the studies, methods of electrical technology theory and computer mathematic simulation with COMSOL Multiphysics software environment are used. Results of the study. The study novelty lies in the elaboration of procedure for constructing formulas for calculating the resistance heating three-electrode furnace bath “star” and “triangle” currents with electrode arbitrary location and dissymmetric current system feeding the bath. Influence of the round electrode embedding diameter and the diameter of their dissociation in the three-electrode furnace bath into the currents flowing from the electrode surfaces to the bottom and from the electrode to electrode passing the melt in cases of three-phase symmetric electrode current system and geometrical symmetry of electrode location in the bath is studied. Findings. Calculation procedure of the resistance heating three-electrode furnace bath “star” and ‘triangle” currents with arbitrary electrode location is developed based on the joint use of the direct admittances and difference-potential coefficients of the equivalent circuits.