Modularity clustering based detection of coherent groups of generators with generator integrity indices

Coherent groups of generators, i.e., machines with perfectly correlated rotor angles, play an important role in power system stability analysis. Traditionally, the coherency analysis is carried out offline, whereby the number of coherent groups of generators is determined in advance. We present an alternative real-time methodology for coherency detection based on modularity clustering of synchronization coefficient matrix. The proposed approach not only accomplishes real time coherency detection but also provides the network integrity indices (splitting, connectivity and modularity indices) for studying the dynamic behavior of the power system. Our methodology is simple, fast, and computationally attractive. A simulation case study on the IEEE 39 bus system consisting of 10 generators following a typical fault demonstrates the efficacy of our approach.