Earth Faults in Isolated Networks / Earth Fault Compensation (with Petersen coil)

Handling of the Transformer Neutral

- low impedance grounding
- isolated transformer neutral
- ground with earth fault compensation coil

Earth Faults

arc self-extinguishes if the the fault current is low enough (no tripping required)


EarthFault_vsd~3-phase.png

log(RF1)     log(RF2)     log(RF3)




EarthFault_vsd~MV_LV.png

EarthFault_vsd~earth fault.png

EarthFault_vsd~fault current.png

GF1 (0 no fault, 1 earth fault)   x length   g/ωc   1/XNE  


EarthFault_vsd~compensation setting.png

EarthFault_vsd~UNE.png

Earth Fault Localization



EarthFault_vsd~localization.png

length a   length b   g/ωc   1/XNE  



Double Earth Fault



EarthFault_vsd~1~alt.png

EarthFault_vsd~2a.png

EarthFault_vsd~2b.png

EarthFault_vsd~2c.png