The Proposal of a Transformer Model With Winding Made of Parallel 2G HTS Tapes With Transpositioners and its Contact Cooling System

When rated current of the transformer windings is higher than the critical current of the used HTS tape, it is necessary to use parallel tapes. As a result, the currents flow in individual parallel tapes is uneven, whose effect is flow of the equalization currents. The compensation of that current could be obtained through mechanical transposition of the tapes in proper “transpositioners.” In order to test the applicability of the “transpositioners,” a transformer model as well as the cooling system of the HTS winding, based on two cryocoolers, was designed. In order to check whether all elements of the cooling system has been properly designed, and thus the system will be able to obtain and maintain a temperature of 77 K, thermal balance of the system was performed by analytical calculations as well as by a numerical analysis. Finally, the cooling system was build and prepared for experimental investigation.