The High Temperature Superconductivity (HTS) Coils project proposed by sponsor Ernesto Bosque, Ph.D. of the Applied Superconductivity Center (ASC) focuses on the delivery of electricity to new electromagnets he and his colleagues have developed. By inserting one magnet into another, magnetic fields combine making the magnet stronger. We created an improved electrical current lead that powers the smaller magnets inserted into larger magnets.
These ASC test magnets require temperatures far below room temperature to work (-267 °C), so liquid helium is used as a coolant. The limitations of available current leads have to do with the effect (heat) of current passing through anything. There are two sources of heat: the electrical resistance of the material and the heat of the surrounding test environment. These heat sources cause the liquid helium to evaporate. To improve the efficiency of the magnet testing, the current lead needed to be redesigned.
To overcome the heat problems, the team used material science, thermal fluid sciences and a more efficient mechanical configuration than currently used. The goal was to design a current lead that provides 1000 amps while losing no more than four watts of heat, providing enough electricity through the current lead to power the magnet and reduce liquid helium evaporation.