Abstract：A new concept called as non-linear stability factor which can be used to analyze power system stability under large disturbance is first proposed in this paper by researching the transform process of abridged cross-term and third order-term in normal form second-order transformation. That is damping factor and stability domain factor. The variation speeds of normal form variable amplitude under large disturbance can be analyzed by damping factor. On this basis, normal form variable stability domain under large disturbance can be acquired by calculating the stability domain factor, and then judging the system stability. These information of stability cannot be obtained from the existing analysis theory and method, so it provides a feasible approach to analysis the system stability by using another point of view. Simulation results of an example prove the correctness and effectiveness of the proposed concept.
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2010, Vol. 25 
