Optimization and Cold Test of a Triaxial 2G HTS Power Cable with High
Current Capacity
Abstract
Triaxial HTS AC power cables, that incorporates three HTS phases wound
around a single core within a single cable is considering the optimal
solution for low and medium voltages. Such a design permits to save
expensive HTS conductor and to increase the power density transmitted.
It is difficult to increase the transmission capacity of a triaxial
cable by increasing its operating voltage and therefore, insulation
thickness between phases. The other way is to increase the operation
current by using a multilayer structure in each phase of the triaxial
cable. This task demands a complicated optimization analysis and a
precise manufacturing technology. Following our previous studies, we
developed and tested the triaxial cable prototype with two layers per
phase made of ReBCO wire. The optimal parameters of the cable (twist
pitch, diameters of phases, etc.) have been determined using the
numerical simulation methods developed. DC and AC tests of the cable has
been performed. In the result, the feasibility to provide a uniform
current distribution in a triaxial cable, each phase of which consists
of two layers, has been demonstrated. With an outer diameter of
~24 mm only, this is the most compact triaxial HTS power
cable manufactured and tested up to date with currents up to 4 kA per
phase. The anticipated power transfer with three phases of this cable
can be as large as ~34 MW.