TY - JOUR T1 - Stable and unstable power swing detecting by improved equal area criterion method TT - شناسایی نوسان توان پایدار و ناپایدار با استفاده از معیار سطوح معادل بسط یافته در حوزه زمان JF - jnsee JO - jnsee VL - 2 IS - 1 UR - http://journals.sut.ac.ir/jnsee/article-1-63-en.html Y1 - 2014 SP - 45 EP - 58 KW - Power swing KW - Equal area criterion KW - Transmission line protection N2 - The equal area criterion method is proposed for the power swing detection. Although this method is good for a single machine system, the method cannot distinguish the stable power swing from the unstable one in a multi machine system. In this paper, a novel method for distinguishing the stable power swing from the unstable one is proposed. In the proposed method the network is separated into the critical and noncritical machines. This method is performed by Digsilent software. M3 ER -