Critical contingencies ranking is one of the most used tools by expansion and operation planners in power systems in order to determine risky security conditions. Some approaches have been proposed, for instance analysis of QV sensibility using modal analysis tools. This paper compares some approaches concerning to contingencies ranking using modal analysis of the Jacobian matrix, which include participation factors analysis, aggregated participation factors and nodal sensibility analysis. The methodologies were used in Matlab and proved with the test system IEEE 118 nodes.