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1 0 7 1. A 20 MVA, 6.9 KV 3-phase 4-pole star connected synchronous motor is operating with field current of 20 Amps, at full load and 0.9 power factor leading. The motor has a synchronous reactance of 1.5 ohm and negligible armature resistance. 30 points a. Find the motor full load torque and power angle. b. If the field current is increased by 15% and the load torque is increased by 15% find the motor current and power factor. With the field current adjusted back to 20 Amps, find the motor maximum torque and the motor current corresponding to that maximum torque c.

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