negative sequence Vs zero sequence for ground fault

[dfdt]

Can we use negative sequence current to detect ground faults on ungrounded system?

 

[dpc]

For single line-to-ground fault, the three sequence networks are in series, so I1=I2=Io= 0 for ungrounded system. In reality there is a small current due to capacitive coupling to ground.

 

[dfdt]

Thanks DPC,and what i understand that there won't be any sequence current to rely on for detecting ground fault (which mainly would line capacitive discharge current)

 

[dfdt]

What are key criterion for setting negative sequence current setting for detecting EF on grounded system? Like would tranposition of line interfere with/encroach on the setting value?