A 50 Hz, 500 MVA, 66 kV, Y-connected three phase synchronous generator is in operation with an internal voltage of 1.0pu. Assume that a three phase fault occurs at its terminal and the circuit breaker operates at 2 cycles. Neglect the saliency. Machine parameters in per unit are given as follows-

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A 50 Hz, 500 MVA, 66 kV, Y-connected three phase synchronous generator is in operation with an internal voltage of 1.0pu. Assume that a three phase fault occurs at its terminal and the circuit breaker operates at 2 cycles. Neglect the saliency. Machine parameters in per unit are given as follows- Xa" 0.12 Ta Xa 1.0 1.1s 0.25 Ta 0.04 s i) Determine the ac component of current in SI value at the instant the fault occurs. ii) Find the total fault current at the instant of the fault which includes ac and dc components. iii) Determine the ac component of current in SI value at the instant when breakers are open. A 50 Hz, 500 MVA, 66 kV, Y-connected three phase synchronous generator is in operation with an internal voltage of 1.0pu. Assume that a three phase fault occurs at its terminal and the circuit breaker operates at 2 cycles. Neglect the saliency. Machine parameters in per unit are given as follows- Xa" 0.12 Ta Xa 1.0 1.1s 0.25 Ta 0.04 s i) Determine the ac component of current in SI value at the instant the fault occurs. ii) Find the total fault current at the instant of the fault which includes ac and dc components. iii) Determine the ac component of current in SI value at the instant when breakers are open.