Development of a tool for the analysis of power system higher order oscillation

The analysis of higher order modal interaction attracts much attention from scholars all over the world. The normal form theory and the modal series method offer new ideas for solving these problems. However, literature review and simulation show that modal analysis for a certain case with these approaches may obtain different results. In this paper, the currently available methods are integrated into a tool PSMAT (power system modal analysis tool), so that one can compare the results with different approaches, and then select the most appropriate method for his analysis purpose. The developed tool has all the functionalities in modal analysis as well as the quantitative indices. The design of the tool is described and case studies are presented. The results obtained with this tool are discussed. It is verified that this tool is effective, in both modal analysis and comparison of the approaches.