engineering recuitment GATE EE 2023-24 Test Series Electrical Machines Alternator and Synchronous Motors Synchronous Motor Power
A 3-ϕ, 5 kVA, 208 V, four pole, 60 Hz, star connected synchronous machine has negligible stator winding resistance and a synchronous reactance of 8 ohms per phase at rated terminal voltage.
The machine is operated as a synchronous motor from the 3ϕ, 208 V, 60 Hz, power supply. The field excitation is adjusted so that the power factor is unity when the machine draws 3 kW from the supply.
If the field excitation is held constant and shaft load is slowly increased, the maximum torque (pull-out torque) that the motor can deliver is __________ (N-m)Enter numerical value using the virtual keypad. Round off where necessary.