The aim of this paper is to analyze the behavior of the power lines, to lightning. The altitude of metal structure in particular types of towers, combined with high soil resistivity, insulation and the coupling between modest guard cables, secundary factors that impair the performance of the power line with a back flashover. This paper has been developed through a model of lightning - structure - grounding, which considers the impact on the components and the activities that will reduce the failure rate in power lines. A case study have considered two power lines with a total length of 603 km, a double circuit from the Mantaro to Socabaya substations, which features fixed serial capacitors and shunt compensation. Finally the method is determined to assess performance and identify priorities for improvement, to prevent loss of function of the power line, to lightning.