Electrical insulation at cryogenic temperatures

Summary form only given, as follows. In order to reduce the size and mass of portable, high power electrical systems cryogenic cooling is being studied. This allows an increase in efficiency in the generator, high current conductors, and power electronic switches, resulting in smaller conductors, lower resistive losses, and more efficient switching. However, the effects of the low temperatures (ranging possibly from 77 K up to ambient) is not well known for many materials and components. Specifically the effects of cryogenic temperatures on the operational characteristics of capacitors and other dielectrically insulated structures is unknown. Although there may be a decrease in losses there may also be material weakening and material expansion/contraction leading to premature failure or changes in the component characteristics. We have done a survey of relevant previous work in this area and are currently planning some basic tests to determine component characteristics at cryogenic temperature. Preliminary results are presented