Controlled Closing of PT Delta Winding for Identifying Faulted Lines

Faulted feeder identification in active grounded networks

“…Equations (14) and (15) are used as the criteria to distinguish between the faulted and healthy feeders. The process of faulted feeder identification begins with the injection of proper current by the active grounding system to limit the fault current to provide the service continuity.…”

“…Generally, the identification of the location of a ground fault has become a challenge in the presence of unbalanced loads connected to the laterals, which is complicated by feeders [30]. From 7, (14) and (15), it can be realised that variations of zero sequence current in the healthy and faulted feeders are a function of fault location. This is due to the fact that the fault location determines the series impedance between the main bus and the fault point.…”

“…In mentioned systems, if a permanent fault occurs, the faulted feeder should be identified and separated from the network in a scheduled manner. In these grounding systems, identification of the faulted feeder is very difficult and complicate [13,14]. The low level of ground fault current in these systems make the overcurrent protection schemes unable to detect the fault.…”

Earth Fault Distance Estimation Using Active Traveling Waves in Energized-Compensated MV Networks

“…This added fundamental current component has been also exploited to find the fault distance. In the same scenario of providing zero sequence current loops toward identifying the faulty feeder, a Earth Fault Distance Estimation Using Active Traveling Waves in Energized Compensated MV Networks Nagy I. Elkalashy, Nehmdoh A. Sabiha and Matti Lehtonen T short period of switching concept is addressed in [16]- [17]. In [16], the neutral is earthed using a controlled-thyristor.…”

“…This provides transient currents in the earth loop for a short period exploited to identify the faulty feeder. In [17], the idea of injecting pulses has been implemented using opendelta/earthed-star transformer. A thyristor has been triggered to close the open-delta windings.…”