Admissible Region of Large-Scale Uncertain Wind Generation Considering Small-Signal Stability of Power Systems

The increasing integration of wind generation has brought great challenges to small-signal stability analysis of bulk power systems, since the uncertainty of wind generation may considerably affect equilibria of the systems. In this regard, this paper develops a conceptual framework to geometrically measure the influence of uncertainty of wind power injections (WPIs) on the small-signal stability of bulk power systems. We define a new concept in the WPI subspace, which is referred to as the admissible region of uncertain wind generation considering small-signal stability (SSAR). To do this, first the traditional concept of small-signal stability region (SSSR) defined in the nodal power generation injection space is extended to a higher dimensional nodal injection space that incorporates both the deterministic generation injections and the uncertain WPIs. Then the SSAR is obtained by mapping the extended SSSR onto the WPI subspace. The polynomial approximation of the SSAR boundary is given in a closed form. Case studies on the modified New England 39-bus system with multiple wind farms illustrate the SSAR concept and its potential applications.