Influence of Magnetic Shielding on the Power Loss of Induction Heating Power Supply in the Electro-magnetic Induction Controlled Automated Steel Teeming System

In order to reduce the influence of ladle structure on the power loss of power supply in the electromagnetic induction controlled automated steel teeming (EICAST) system, a method of setting magnetic shielding material on the bottom and sides of induction coil is firstly proposed. The influence of the magnetic shielding on the magnetic flux density and the optimal heating position of induction coil are analyzed by numerical simulation, and the correctness of simulation results is verified by laboratory experiments. In addition, the best magnetic shielding sizes and structure for this new technology are determined respectively. The results show that the magnetic shielding method can effectively reduce the power loss of induction coil and improve the optimum heating area of induction coil. When using copper as a magnetic shielding material, the best sizes of magnetic shielding are height of 200 mm, length of 290 mm, width of 290 mm and thickness of 1 mm. At this time, the best heating position of induction coil will move upward, and the moving distance is 20.2 mm, which is beneficial to the installation of induction coil and the improvement of its service life. To improve the strength of nozzle brick and ensure the service life of nozzle brick, a new structure is applied, and its magnetic shielding effect is almost the same as the former. These research works are very important for the wide application of the EICAST technology.