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What is the phase current in phase Y and in phase B out of R-Y-B when sudden short circuit to all three phases occurs at no load? It is given that after fault current in phase R is equal (Vm Sin ωt)

What is the phase current in phase Y and in phase B out of R-Y-B when sudden short circuit to all three phases occurs at no load? It is given that after fault current in phase R is equal (Vm Sin ωt) Correct Answer Y = Vm Sin(ωt +120°) & B = VmSin(ωt+240°)

The given phase sequence is R-Y-B . When all three phases are short circuited then the fault is symmetrical that means fault current flowing through each phases will be 120° apart from each other.

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