Operating experience of Hokkaido-Honshu high voltage direct current link

The Hokkaido-Honshu HVdc link was increased to 600MW m 1993. In the dc link, new devices and equipment, such as light-tnggered thyristors, dead-tank type dc filters and so on, are employed. This dc linlk features a unique control system, Automatic Frequency Control (AFC) , applying mcdem control theory. This paper describes these new techniques and operating experiences. The Tohoku Region, where the one t d is loc ated, was hit by a large earthquake in 1994, the effects and damages to the equipment was described in this paper.