Abstract:

The most effective way of increasing switching abilities of high voltage circuit breakers in energy transmission systems is to influence around zero degree to short circuit currents (Maljkovic Z et al 2000; Gashimov, A.M et al. 2001;Antipov, K.M et al. 1985; Gashimov A.M 1991). For this reason, transformers neutral points should be grounded variously for limitation of asymmetric short circuit currents. But another way for this limitation is grounded of transformers neutral points over non-linear reactor. The non-linear reactor effects around zero degree to short circuit current. Therefore, the main purpose of non-linear reactor is to increase the switching abilities of the high voltage circuit breakers. This kind reactor does not necessitate the isolation exchange of transformer neutral points. Non-linear reactors effect around zero degree to asymmetric short circuit current at the networks, which their neutral point, have been grounded with non-linear reactors. In addition, it also effects to changing speed of temporary recover of voltage, which occurred, between contacts of high voltage circuit breakers after removing of short circuit. So increasing switching abilities of the high voltage circuit breakers will be provided by these two ways. Therefore, switching abilities of transformers neutral point the networks with 220 kV or higher can be increased by grounding over non-linear reactor.

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