Energy Expenditures in a High-Voltage Three-Phase AC Superconducting Cable

Abstract

Protection against short circuits between buses tubes in short networks of ore-thermal furnaces is provided by means of electrical insulation. Failure of the insulation leads to an arc, and then to the complete destruction of the expensive bus tube package. Disconnection fault in the elements of a short network cause overheating of undamaged elements. Currently, emergency modes of operation of a short network are determined with indirect signs. It is impossible to use current protection for this purpose because of the existing restrictions on the number of current transformers and the place for their placement. The authors developed a current protection of short networks of ore-thermal furnaces from electrical damage on a single magnetic current transformer. The proposed protection is simple in design, it is able to identify breaks in the elements of a short network and protect them from short circuits. The location of the magnetic current transformer relative to the bus tube package is determined based on the simulation of the magnetic field. The article describes a method for simulating the components of the magnetic field of a bus tube package, which allows us to model them in operational and emergency modes with an error of no more than 10%.