Uma técnica para detecção de faltas em linhas de transmissão de corrente contínua por meio da energia da derivada de sinais.

Abstract

In this work the energy transmission is studied and the main contribution is the development of a new algorithm for fault detection in direct current (DC) transmission lines. This method uses the synchronized voltage and current data, so that fault detection is performed redundantly. In addition, a classical method of fault location and classification on transmission lines is applied together to the proposed detection method. The location method is based on the theory of traveling waves. Three configurations of electric power transmission systems using High Voltage Direct Current (HVDC) technology are simulated: a monopolar system, a bipolar system and a hybrid system composed of alternating current (AC) and DC lines, and a multiterminal system. The developed fault detection method uses the signals derivative calculation, energy calculation of coefficients and a self-adaptive threshold. The results are analyzed considering absolute errors, percentages and admissible errors. Finally, it is observed that the percentage errors obtained in the fault location are not higher than 0.33% for the monopolar system, 0.82% for the bipolar system, and 0.56% for the hybrid system, so, 0.82% is the maximum percentage error for all 1980 cases of analyzed faults, even for cases with high value of fault resistance. Faults are correctly detected at 100% of the simulated cases of faults in monopolar, bipolar and hybrid. The proposed method stands out for presenting similar results to well known transforms, such as wavelet, and using a self-adaptive threshold and redundancy.