ZERO SEQUENCE CURRENT GENERATOR

摘要

A facility for an identification of an earth-fault feeder in networks with an isolated neutral comprises filters of zero sequence currents, which are included in a circuit of each outgoing filter, and the filter of the zero sequence voltage, which is connected to busbars. A generator of zero sequence current is connected to busbars through a switch, which is controlled by means of control and operation module, which is connected to the zero sequence voltage filter and which accomplishes temporarily closing the above- mentioned switch, when zero sequence voltage exceeds its definite level. The control and operation module comprises a time delay and provides with an identification of one phase-to-ground fault with respect to the zero sequence. The zero sequence current generator comprises a reactor with three-phase non-saturable iron circuit and with windings, which are connected in star with a grounded neutral. To the control and operation module there is connected a drive in the form of series-connected selector and vacuum switching module with three vacuum switches.