Celilo Converter Station

The Celilo Converter Station, built in 1970 and owned and operated by the Bonneville Power Administration, is the northern terminus of the Pacific DC Intertie, near The Dalles, Oregon, in the United States.HistoryThe Celilo Converter Station was originally configured with six groups of six-pulse mercury arc valves with a blocking voltage of 133 kV each (for a total of ±400 kV) and a maximum current of 2,000 amperes.In 1985 two six-pulse valve groups of thyristors were added to increase the voltage to 500 kV per pole for a total differential voltage of 1,000 kV.In 1989 two new 1,100 ampere, 500 kV thyristor converters were added in parallel with the two existing converters, giving a total transmission power of 3,100 Megawatts (3,100 A at ±500 kV).Until September 2001, the Celilo Converter Station was partially open to the public and included displays describing the history of DC transmission and the Pacific Intertie, but security concerns have closed this facility to the public.