Application of Coherency Property of Generator to Analysis of Low-Frequency Oscillation in Power System

Abstract:

Coherency is used to characterize the degree of confusion between generators which oscillate against each other, so it can judge the process which generators oscillate from local mode to inter-area mode. The coherency is the value of the direction cosine by using angle of the generators. when the direction cosines of two generator is 1 that indicates the oscillation direction between the two generators is inter-area oscillation mode; when the direction cosines of two generator is-1 that indicates the oscillation direction between the two generators is local oscillation mode. Coherency is affected by speed governing system and excitation system of generator.Using two area systems verifies the theoretical analysis is correct.

• Periodical: Advanced Materials Research (Volume 827)
• Pages: 136-141
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.827.136
• Online since: October 2013
• Authors: Zhi Jian Liu, Rong Huang, Shu Ming Zhou, Qi Song
• Keywords: Coherency, Inter-Area Mode, Local Mode, Low Frequency Oscillation (LFO)

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