Fault analysis of HTS power transmission cables

It is very attractive to replace traditional power cables into high-temperature superconducting (HTS) cables for electricity transmission to metropolitan areas with the advantages of high capacity and low losses. However, these advantages only present when the conductors are kept in certain low temperature. When over-voltage or over-current occur, the HTS cable may quench and the resistivity of the conductor will increase rapidly which will result in the reduction of transmission capacity, increase of the power loss or even electrical insulation breakdown. Therefore, it is necessary to investigate the level of over-current and overvoltage. In this paper, an accurate model for a 1-km-long 110 kV HTS cable is presented and a simple simulation model for power system containing HTS cable is built up using EMTP-ATP program. Single-phase short-circuit fault and electrical insulation breakdown fault are considered to investigate the over-voltage and over-current level of HTS cable. The simulation results may provide instructive guide for the protection systems for HTS cables.