AC or DC Furnace Transformers
The Electric Arc Furnace and Ladle Furnace Transformers are the key equipment in a steel plant, therefore specific engineering solutions are adopted in order to guarantee over time the best performances under the dielectric, thermal and mechanical stresses which daily involve these transformers.
Furnaces transformer’s life is affected by heavy stresses during operation. Frequent on and off switching, high magnitude inrush currents, high operation currents, often close to short circuit values, fast transient overvoltages, significant harmonic content and elevated number of operations carried out by the on load tap changer are the everyday challenges for a furnace transformer.
Electrical stresses are due to overvoltages generated both by the melting process and by transient state resulting from a sudden disconnection of HV circuit breakers, especially if vacuum-type ones are installed. Tamini pays special attention to this issue adopting a specific design and manufacturing procedures to guarantee a stronger transformer insulating structure.
Moreover during furnace operation, the transformers undergo thermal and mechanical stresses due to the continuous daily steel melting process. Continuous stresses and vibrations might make the windings loose if they are not properly treated and robustly clamped. In order to avoid any inconvenience due to such heavy and frequent stresses, Tamini has adopted improved procedures for windings pressing and thermal treatment operation.
Different solutions can be adopted according to the customer requirements: