5-7. A 208-V Y-connected synchronous motor is drawing 50 A at unity power factor from a 20...

5-7. A 208-V Y-connected synchronous motor is drawing 50 A at unity power factor from a 208-V power system. The field current flowing under these conditions is 2.7 A. Its synchronous reactance is 1.6 Assume a linear open-circuit characteristic.

(a) Find and EA for these conditions.

(b) Find the torque angle

(c) What is the static stability power limit under these conditions?

(d) How much field current would be required to make the motor operate at 0.80 PF leading?

(e) What is the new torque angle in part (d)?