Detecção de ilhamento em sistemas de transmissão com geração eólica conectado ao sistema interligado nacional

Abstract

With the increase in renewable energy sources today, some undesirable events occur, one that we can mention is the islanding of these sources. Considering this type of occurrence in wind farm X, where it was verified twice at different times and with different characteristics of load, generation, and final configuration after islanding. One of the occurrences was with the islanding of the park along with the connection city, at this moment the park continued to supply the city for a certain time. In the second occurrence of islanding, the auxiliary services of wind turbine B and the collector substation served as a load for wind turbine A. In both cases, there was under-voltage or over-voltage, however, with values within the limits set for this protection. The other protections of the substation also did not reach values to avoid islanding. A survey of the methods and existing protections and under study was carried out in order to verify the possibility of use in the occurred event. Using the Simulink tool from Matlab®, the behavior of the standard system was analyzed, using Park's transform as a basis, in relation to short circuits and islanding, reaching a dynamics of these occurrences. With the analysis of these real and theoretical occurrences and through modeling in the Typhoon® Control center simulator, the settings found in the said park were tested to replicate the involved events. Through the analysis of the results and the existing anti-islanding protections, a protection was proposed through measurements of voltage levels in the direct axis and zero, through Park's transform, and consequent shutdown of the machines. Subsequent tests of this protection were carried out where various scenarios were simulated in the Typhoon® Control center, as analyzed in the oscillographs of real occurrences to verify the operation of the proposed protection.