coherency identification of generators using a pam algorithm for dynamic reduction of power systems相干识别发电机使用pam算法的动态电力系统还原.pdf

Energies 2012, 5, 4417-4429; doi:10.3390/en5114417 OPEN ACCESS energies ISSN 1996-1073 /journal/energies Article Coherency Identification of Generators Using a PAM Algorithm for Dynamic Reduction of Power Systems Gi-Chan Pyo *, Jin-Woo Park and Seung-Il Moon School of Electrical Engineering and Computer Science, Seoul National University, Seoul 151-742, Korea; E-Mails: jwpark@powerlab.snu.ac.kr (J.-W.P.); moonsi@plaza.snu.ac.kr (S.-I.M.) * Author to whom correspondence should be addressed; E-Mail: draco99@powerlab.snu.ac.kr; Tel.: +82-2-886-3101. Received: 15 September 2012; in revised form: 31 October 2012 / Accepted: 31 October 2012 / Published: 8 November 2012 Abstract: This paper presents a new coherency identification method for dynamic reduction of a power system. To achieve dynamic reduction, coherency-based equivalence techniques divide generators into groups according to coherency, and then aggregate them. In order to minimize the changes in the dynamic response of the reduced equivalent system, coherency identification of the generators should be clearly defined. The objective of the proposed coherency identification method is to determine the optimal coherent groups of generators with respect to the dynamic response, using the Partitioning Around Medoids (PAM) algorithm. For this purpose, the coherency between generators is first evaluated from the dynamic simulation time response, and in the