HTS current leads for the LHC

Leads for transferring heavy current from power converters, working at room temperature, into the liquid helium environment required to operate superconducting magnets, have been long recognized as being an immediate application of the emerging technology of high temperature superconductivity. By correct dimensioning of such leads it should be possible to reduce significantly the cryogenic load which these leads represent. The Large Hadron Collider (LHC) under construction at CERN is by far the largest user of superconducting magnets requiring the transfer of over 3 million amperes of current, and therefore has much to gain from the use of this technology. After a brief reminder of the motives and the outline of the project, a review is given of the program to provide helium gas cooled current leads incorporating HTS sections.