Electrical Mach...

A synchronous motor with negligible armature resistance runs at a load angle of 20° at the rated frequency. If supply frequency is increased by 10%, keeping the other parameters constant, the new load angle will be

Find the output torque(in N-M) of the 3ϕ synchronous motor has a 480 V, 60 Hz, 4 poles drawing 40 A of current at full load, unity power factor.

Assuming the motor is lossless.

A 400 V, 3-phase star-connected synchronous motor has x_d = 8 ohm and x_q = 6 ohms. It is running on infinite bus. If its field current is reduced to zero, the maximum load that the synchronous motor can carry is ___________ (in kW)

A 3-phase, 460 V, 6-pole, 60 Hz cylindrical rotor synchronous motor has a synchronous reactance of 2.5 Ω and negligible armature resistance. The load torque, proportional to the square of the speed, is 398 N.m at 1200 rpm. Unity power factor is maintained by excitation control. Keeping the v/f constant, the frequency is reduced to 36 Hz. The torque angle δ is

A three-phase synchronous motor has 80% of synchronous reactance and negligible resistance. When connected to bus bars at rated voltage and the excitation adjusted for an emf of 120%, the machine draws an input kVA of 100%. The mechanical power developed by the motor, by neglecting all the losses is

A 500 V, three phase mesh connected synchronous motor runs at rated voltage and with an excitation emf of 600 V. Its synchronous impedance per phase is 0.4 + j3 Ω. The line current for maximum power input is _______ 

A 6.6 kV, Y-connected, 3-phase synchronous motor operates at constant voltage and excitation. Its synchronous impedance is 2 + j20 Ω/phase. The motor operates at 0.8 leading power factor while drawing 800 kW from the mains. If the motor is loaded to draw increased power of 1200 kW, the power factor will be _____