On-site testing of partial discharge for 750 kv shunt reactors

Summary

High voltage shunt reactor is an indispensable equipment in high voltage and long distance transmission network. Its security and stability affect the safety of power grid directly. With the great construction of 750 kV ultra- high voltage long distance transmission lines, the application of 750 kV shunt reactor is greatly increasing in Northwest China power grid .However, lots of problems of 750 kV shunt reactor have come up, and the testing method of which is limited. So far, there is no precedent for the partial discharge test of 750 kV shunt reactor in China. In order to judge the state of the reactor and improve the stability of power grid effectively, it is necessary to carry out the research on the partial discharge of 750 kV shunt reactor. In this paper, a method of the partial discharge test was carried out. This partial discharge test could help to find the internal defects of reactors timely, and increase the reliability of 750 kV shunt reactor in operation. Methods for on-site partial discharge test of 750 kV shunt reactor were studied at an elevation of about 3000 meters above sea level. The partial discharge test circuit was designed by using series resonance method. The parameters of the main circuit parameters were calculated. The detection sensitivity of partial discharge detection circuit and the way of anti-interference were analysed to increase the measurement accuracy. The design of compensation capacitor, variable-frequency power sources, excitation transformer and filter reactor was carried out, which provides the basis for the development of test equipment and on-site test. Considering the influence of 3000 meters above sea level, the correction factor was added in design process. The research results of this study could be applied to the Northwest Power Grid 750 kV shunt reactor on-site test work, and could create great economic benefits.

Additional informations

Keywords

High voltage shunt reactor, Partial discharge test, High altitude, Fault diagnosis, Series resonance