Considerations for ground fault protection in medium-voltage industrial and cogeneration systems

Microgrid Protection Challenges and Mitigation Approaches–A Comprehensive Review

“…This is due to the concern that a next-ground contact of the other pole may induce pole-topole fault and serious damage to the system. Hence, a ground single-pole fault location and detection in an ungrounded DC power system are complex because of low ground-fault current [133], [134]. An additional drawback of this scheme is that the existence of even minor leakage currents in the DC power system which do not have a path to the ground can lead to an uncertain DC offset because of DC bus has no DC reference points to balance the DC power [135].…”

Ground fault location self-diagnosis in high resistance grounding drive systems

“…However, most of HRG GFI methods and papers focus on system level detection, such as generators, substations, power distribution panels, and so on [1][2][3][4][6][7][8]. Different methods must be combined in order to find the location of the fault.…”

“…As a result, National Electric Code (NEC) mandates the use of ground fault indicators when a ground fault occurs. References [1][2][3][4][6][7][8] discuss various Ground Fault Identification (GFI) methods in HRG systems.…”

Hybrid Energy Storage Implementation in DC and AC Power System for Efficiency, Power Quality and Reliability Improvements

“…This is because of the fact that a second ground contact in another pole can cause a pole-to-pole fault and significant system damage. However, a single pole ground fault detection and location in an ungrounded system is very difficult, as it is seen similarly by different detectors in the system due to the low ground current [179]- [181]. Another disadvantage of this configuration is that, without a DC path to ground, the presence of even small leakage currents can cause an unpredictable DC offset since there is no DC reference point for the DC bus to be balanced [182].…”