Rede de sensores sem fio para aquisição de dados de malhas de aterramento submetidas a correntes impulsivas.

Abstract

In this work, it was developed a data acquisition system capable of acquiring impulsive signal of voltage and current. With these data it is possible to evaluate the degradation conditions of energized grounding grids. The system comprises a wireless sensor network, able to acquire signals resulting from injection of high intensity current impulses on different points of the grounding grid. The system developed was assessed by experiments using a high intensity current impulse generator, which is able to simulate atmospheric discharge signals. In these experiments, they were acquired signals simultaneously with an oscilloscope and with the proposed system. Comparing the signals acquired by the two forms, it resulted in 99.9% similarity. After proven effectiveness, the data acquisition system developed has been used in assessing the operating conditions of an actual grounding. From the results obtained, one can observe that the system was capable of acquiring data originating from the application of current impulses in the soil, transmit them using wireless communication, and perform processing such data. The use of a wireless sensor network reduces the influence of electromagnetic effects present in electrical substations, on the measurement systems. In addition, remote measurement provides greater security to the professionals involved. Thus, from the data acquired it is possible to issue an evaluation of degradation conditions of an energized grounding grid and build models that are useful in planning and prediction of grounding faults. Therefore, the system provides the adequate conditions for the study of high currents, voltages and frequencies and their effects.