Fuzzy c-means clustering for power system coherency

This paper presents the application of fuzzy c-means (FCM) clustering to the recognition of coherent generators in power systems. A coherency measure, which is derived from the time-domain dynamic responses of generators, is first proposed for evaluating the property of generator coherency. From the coherency measure a fuzzy relation matrix describing the degree of coherency between any pair of generators is constructed. Fuzzy c-means clustering analysis is applied on coherency measure. The result of various coherent generator groups can thus be obtained, showing results of clustering for different prescribed number of coherent groups. Application results of a sample power system are presented to show the validity and effectiveness of the proposed method.