| 摘要 |
The invention relates to a method and a device for carrying out the latter, for selectively identifying and localising high-ohm, single-pole earth faults in neutral-point compensated electric supply networks. According to the invention, at least one auxiliary signal with the network frequency omega N is supplied to the zero current system of the network. The auxiliary signal is supplied in such a specific way, that the neutral-point biasing voltage U ne( omega N) is substantially compensated at the network frequency omega N. The identification and localisation of high-ohm, single-pole earth faults is thus carried out at a compensated neutral-point biasing voltage Une( omega N). The invention also relates to a method, according to which the earth-fault neutraliser can be tuned to the supply network even at a compensated neutral-point biasing voltage Une( omega N). |
