DEFINITION AND CLASSIFICATION OF POWER SYSTEM STABILITY

Power system stability broadly defined as the property of power system that enables it to remain in a state of operating equilibrium under normal operating conditions and to regain an acceptable state of equilibrium after being subjected to a disturbances. Instability in Power system manifested in many different ways depending on the system configuration and operating mode. The problem of defining and classifying Power system stability has been addressed by several previous CIGRE and IEEE Task Force reports. These earlier efforts, however do not completely reflect current industry needs, experiences and understanding. In particular, the definations are not precise and the classifications do not encompass all practical instability scenario. This report aims to define the issue of stability definition and classification in power systems from fundamental view point and discuss linkages to related issues such as power system reliability and secuirity.