This paper is predicated on a unique coherency identification technique, which is evident and decisive. This coherency testimony technique has the capability to spot the coherent teams accurately, that the essence of the machines within the reduced order system is sort of almost like those of the complete system. The technique involves the alpha index, delta index and a power variation index for each pre-fault and at the moment of initiating fault condition to pick out the coherent cluster of generators. These indices have the capability to see the optimum coherent teams of generators with reference to dynamic response. The Dynamic equivalent construction method is being used to replace each coherent group of generators with a single machine. Thus less computer storage and time are needed in finding the swing equations. The projected coherency identification methodology has been applied on IEEE 39 bus test power system considering three different cases and therefore the obtained results well-tried that the proposed technique is very effective in deciding the coherent teams of generators with high accuracy.