A 10-hp, 230 V, 60 Hz, three phase Y- connected, synchronous motor delivers full load at a power factor of 0.707 leading. The synchronous reactance of the motor is j5 Ω per phase. The rotationnal loss is 230W and the field winding loss is 70W. Calculate
a. The generated voltage
b. The efficiency of the motor. Neglect the armature winding resistance
A 208-V Y connected three phase synchronous motor has a synchronous reactance of 4Ω per phase and negligible armature winding resistance. At a certain load the motor take 7.2kW at 0.8 pf lagging. If the power developed by the motor remains the sam while the excitation voltage is incresae by 50% by rasing the field excitation, determine:
a. The new armature current
b. The power factor