A Description of Discrete Supplementary Controls for Stability

Transient stability is a characteristic that must be considered whenever an electric power system is expanded. Transient control methods using conventional continuous controls are well documented, but transient control can also be achieved using discrete control methods. This tutorial paper presents descriptions of ten discrete transient stability controls. Each description tells how the control acts to maintain stability, what effect its operation has on generating station mechanical and electrical equipment, and provides references to detailed articles. The paper could serve as a starting point for detailed investigation of a particular control method.