The development of protection and monitoring system for high temperature superconducting cable

The research and development of high temperature superconducting (HTS) power cable systems have attracted much attention in recent years in China. The first HTS power cable system in China was expected to be in field operation early in 2004 in the PuJi substation in Yunnan Province. In order to keep the HTS cable operating safely and reliably on a utility electrical network, a protection and monitoring device has been developed. The protection scheme is presented and a thermal balance model of the HTS cable on quench is proposed, with which the over-current limit value and thermal accumulation limit value of the HTS cable are determined. In order to study the characteristics of the HTS cable system and accumulate commercial operation experience for it, the device also offers an operation-state record of the HTS cable, including all the non-electric and electric signals.