Transmission capacity design of underground power cables installed in deep tunnel

Tunnel installation for underground transmission line by electric power cables is often employed in Japan because it is capable of high density power-transmission by multiple cables mainly in extra-high-voltage power cables and because it is easy to install additional cables and maintain them. In addition, because of recent advancements in construction technology, shield tunnels tend to be constructed further into the deep ground to avoid being overcrowded with the other underground objects. This paper reviews Japanese Electric Technology Research Association reports and others as a transmission capacity design focusing in case of tunnel installation and also report those verification test outcomes and the evaluation results