A synchronous generator operates initially at steady state with a mechanical power of 1pu and a corresponding maximum electrical power of 2.5 pu. Calculate the initial load angle. A three phase to...

A synchronous generator operates initially at steady state with a mechanical power of 1pu and a corresponding maximum electrical power of 2.5 pu. Calculate the initial load angle. A three phase to earth fault occurs on the associated bus reducing the maximum electrical power to 0.9 pu. After the clearance of the fault by automatic switchgear operation the maximum electrical power rises to 2.1 pu. Calculate the load angle after the clearance of the fault. Calculate the critical clearing angle. Calculate also the accelerating and decelerating areas. Comment on the accelerating and decelerating areas.