Small signal analysis of power systems: Eigenvalue tracking method and eigenvalue estimation contingency screening for DSA

Two aspects of small signal analysis of power systems are investigated in this dissertation. The first part presents the eigenvalue tracking method for power system stabilizer (PSS) placement. Traditional methods for determining PSS placements are based on the analysis of the interconnected system. However, the design of the PSS is based on a simplified single machine infinite bus (SMIB) model. A new method, the eigenvalue tracking method, makes a connection between the interconnected and system of SMIBs models to determine PSS placements. Thus, this method bridges the relationship between the way a PSS is designed and placed. This method will be compared to traditional methods for PSS placement, and it will be shown that the eigenvalue tracking method can outperform the traditional methods and should be included for a complete analysis to determine PSS placement.The second part of this dissertation develops a new line outage screening method for dynamic security analysis (DSA). The new screening method extends the use of distribution factors commonly used in static security analysis (SSA) to DSA by using the factors with eigenvalue sensitivities to estimate the change in the eigenvalues due to a line outage. This method screens line outages by estimating the stability of the post-line-outage system equilibrium point. Using the estimated changes in the eigenvalues, several line outage severity indices will be created. These severity indices will be used to rank line outages in order of severity and will also be combined with the eigenvalue estimation screening method to form a more conservative line outage screening method.