bus section

One of the current issues in a complex electrical network with isolated (compensated) neutral is the selective identification of the damaged element during a single-phase-to-ground fault (SPGF). In order to achieve selective and reliable operation of protections against SPGFs in complex networks with isolated (compensated) neutral, besides information about the zero-sequence current and connection, information about phase voltages, zero-sequence voltage of the electrical network, and the operation of protection devices against adjacent SPGFs is necessary.

One of the problems in the electrical network with isolated (compensated) neutral is the selective determination of the damaged element in a single-phase earth fault. For selective and reliable operation of protections against single-phase earth faults in networks with isolated (compensated) neutral, in addition to the zero-sequence current, information on phase voltages and zero-sequence voltage of the electrical network is required. Many transformer substations do not have traditional electromagnetic voltage transformers.