The communication device and other devices are required for
the comparison between both sides of current due to the development
of long distance HTS power cable. For that reason, the
authors propose a novel fault detection scheme of differential protective
relay using electrical characteristics of HTS power cable as
shown in Fig. 3. The HTS power cable consists of a conducting and a
shield layers for carrying the required current. The direction of
shield layer current reverses against the conducting layer current