The sequence components of the fault current are as follows:

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The sequence components of the fault current are as follows: I_positive = j1.5 pu, I _negative = – j0.5 pu, I_zero = – j1 pu. The type of fault in the system is

1. LG
2. LL
3. LLG
4. LLLG

Correct Option: C

Given, I_a1 = j 1.5 p.u.

I_a2 = – j 0.5 p.u. and,

I_a

I_a0

I_b

α²

I_a1

I_c

α²

I_a2

I_a0 = – j 1.0 p.u.
then, I_a = I_a1 + I_a2 + I_a0 = 0.
In case of LLG faults at terminal b, c, the conditions at the faults are characterized by V_b = 0, V_c = 0, I_a = 0, as shown in figure also