Generator testing of hydro-power plants in the Pacific Northwest: impact on system studies

The Corps of Engineers (COE) is operating major hydropower projects in the Pacific Northwest, including Columbia-River plants such as Chief Joseph (2614 MW), John Day (2158 MW), The Dalles (2080 MW), McNary (1120 MW) and Bonneville (1224 MW). Dynamic behavior of these plants has significant impact on stability of the entire WSCC system, as demonstrated by the August 10, 1996 WSCC system outage. Therefore, correct modeling of these generators is necessary in planning studies for determining safe stability limits and establishing operating nomograms. General observations of the COE generator testing are presented. The objective of this investigation is to evaluate impact of new data on system studies: voltage support, first swing stability and power oscillations damping.