Dielectric Characterization of NKN in LN2 Using a Proposed Arrangement

This article presents the next stage of the ongoing development of equipment designed to carry out both non-destructive and destructive characterizations of dielectric materials at cryogenic temperatures for application in HTS power systems. The equipment is designed to measure electric permittivity, dissipation factor (“tan δ”) and dielectric strength of electrical insulating materials under a liquid nitrogen bath and 50–60 Hz. In this work, we present the concept test of the proposed equipment, as well as measurements of the aforementioned dielectric properties in laminated sheets of polyimide film with aromatic polyamide paper (NKN), and also sheets of polyamide paper (Nomex) separately. This laminated material was applied in the first Brazilian HTS power cable project. Results obtained with the concept under test are compared with other measurements available in literature. The proposed equipment concept is functional even for a simple assembly of parts.