Very low impedance (VLI) superconductor cables

High Temperature Superconductor (HTS) cable is regarded as one of the most promising new technologies to address grid bottlenecks. Among HTS cable designs, one in particular-shielded cold dielectric cable-offers performance advantages particularly well suited to today's siting, reliability and performance challenges. Shielded cold dielectric HTS transmission cables feature lower electrical losses; the virtual elimination of stray EMF; and significantly lower impedance than conventional cables and lines. Of particular importance, the very low impedance (VLI) inherent in cables of coaxial design makes it possible to control power flows over VLI circuits. In addition, variable impedance may be cost-effectively added to VLI circuits with relatively small angle, conventional phase angle regulators. Thus, VLI circuits can function like fully controllable DC circuits. The introduction of VLI cable enables new approaches to important challenges in grid management. The strategic insertion of relatively short segments of VLI cable to bridge bottlenecks can offload flows from overburdened conventional circuits, thereby expanding grid capacity, extending the useful life of conventional network elements, and raising overall asset utilization. With power markets in turmoil and transmission increasingly the center of attention, VLI cable is a breakthrough technology that has great potential as a cost-effective solution for many of the industry's most pressing problems.