Wide-area measurements-based out-of-step protection system

From time to time a sequence of unexpected and often overlapping contingencies may lead to power system angular instability and even blackouts if not addressed adequately by means of out-of-step protection system. This paper proposes the out-of-step protection system structure, which is based on generation sources electromotive forces vectors angle control. Protection system consists of several, strategically located terminals, exchanging with information in real-time by means of communication network. Protection system structure, principles of operation and implementation problems addressed in the paper, as also IEC 61850 communication standard-based implementation described.