The recent technological advances included in the distribution systems, such as the use of supervisory systems, automation and the emergence of the smart meters brings many possibilities for improvement in the methodologies used in the operation of these systems. This paper proposes a methodology for using state estimation techniques and error detection in smart grids, through measures in the MV network and smart meters to evaluate the voltage profile of the feeder. This evaluation is obtained by calculating an index that analyzes the voltage levels at nodes of consumers according to the ranges appropriate, precarious and critical, further penalizing violations in loads with higher priority or that are in this condition for a long time. The methodology for evaluation can be used to predict the scenarios when changing settings in voltage regulators, seeking to supply energy with a higher quality, thereby increasing consumer satisfaction.