Shin Shinano
Coordinates: 36°8′14″N 137°52′58″E / 36.13722°N 137.88278°E
Shin Shinano (新信濃変電所 Shin Shinano Hendensho?) is the designation of a back-to-back high-voltage direct current (HVDC) facility in Japan which forms one of four frequency converter stations that link Japan's western and eastern power grids. The other three stations are at Higashi-Shimizu, Minami-Fukumitsu and Sakuma Dam.
The HVDC back-to-back facility Shin Shinano uses line-commutated thyristor converters. The station houses two converters, one of which opened in December 1977, the other in 1992. The original 1977 converter was one of the first thyristor-based HVDC schemes to be put into operation in the world and used oil-insulated, oil-cooled outdoor thyristor valves supplied by Hitachi (60 Hz end) and Toshiba (50 Hz end). A special workshop was provided on the site, in which valve maintenance (for example replacing failed thyristors) could be carried out under clean conditions in order to avoid contamination of the oil.
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