3 Phase System Line to Ground fault Fault current calculation

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To calculate the fault current for a 6.6kV, three-phase alternator system with solidly grounded neutrals, the formula I = 3V/(Z0 + Z1 + Z2) is used, where V is the phase voltage of 3.8106 kV. The positive, negative, and zero sequence reactances are given as 0.90 ohm, 0.72 ohm, and 0.30 ohm, respectively. Participants suggest calculating the total current by summing the individual currents I1, I2, and I0, using the provided impedances. Assistance is offered for those who may need help with the calculations, indicating a collaborative approach to problem-solving. The discussion emphasizes the importance of understanding sequence reactances in fault current analysis.
sweetguy_in16
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Six, 6.6kV ,3phase, alternators are connected to a common set of bus bars.
Each has positive negative and zero sequence reactances of 0.90 ohm, 0.72 ohm, 0.30 ohms respectively . An Earth fault occurs on one bus bar . Determine the value of fault current if all alternator neutrals are solidly grounded.

HINT: Fault Current,I =3V/(Z0+Z1+Z2) for single generator when single Line to ground fault occurs.

where, V is the Phase voltage (i.e. ( 6.6kV / 1.732 = 3.8106 kV ))


Can anyone help me on how to solve this problem. Please.
 
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It's been a while, but if memory serves...
Total current = I1 + I2 + I0
You have the impedances. Do one at a time.
I'll do a little book work and see if I can get back up to speed.
Post again if you are still stumped.
I'll try to help.
 

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