Q2/ A 3 phase, 0.8MVA, 3.3kV, 50Hz, SG its armature winding star connected and its iron and mechanical losses are 20kW, having 0.502/phase armature resistance when a 150V is applied to the excitation winding 1-100A at UPF and I, 120A at 0.8 lagging power factor. Find the efficiency at both case

A single phase transformers working at UPFhas an efficiency of 90% at both half load and at the full load of 500 W.Determine the efficiency at 75% of full load and the maximumefficiency.

construct an winding diagram with -4 poles-26 conductors-double layer-simplex wave winding, 2 brushes

Maz a) A sinewave is having a frequency of 50 Hz and instantaneous value of 250 Volts at 1.3 milli seconds. Find D The maximum value of sinusoidal voltage waveform and i) The value of voltage at 2.1 milli seconds. b) Determine the instantaneous equation for the voltage waveform shown in figure, if Vp=100 Volts, Time period is 10 milli seconds and 0 =40 degrees. on Vp Upload your Answers steps in the "Final Answer Submission" Link provided in the Moodle. a) (i) Maximnum value = a) (ii) Value of voltage at 2.1 ms = b) Angular frequency =

A single-phase 111-V, 50-Hz supply is connected to a coil with 200 turns of a coil-core assembly as shown in the given figure. Find the magnitude of maximum flux in the core. (D I N

Answer from the choices below

An Armature runs at 250 r.p.m. and generates an e.m.f. at 50 Hz. There are 216 slots each containing 5 conductors. The winding is distributed and full pitch. All the conductors of each phase are in series and flux per pole is 30 mWb which is sinusoidal distributed.Calculate the number of pole.

A load is operating in a chopper circuit as shown in the figure. It has a duty cycle of 0.4 and chopping frequency is 150 Hz. (consider continuous operation). The value of E is L=0.06H 200V (B) 80V (D) 50V (A) 70V (C) 60V

A 20 kVA, 2000/200-V, 50-Hz transformer has a high voltage winding resistance of 0.2 2 and a leakage reactance of 0.242. The low voltage winding resistance is 0.05 2 and the leakage reactance is 0.02 2. Find the equivalent winding resistance, reactance and impedance referred to the (i) high voltage side and (ii) the low-voltage side. (Draw the related equivalent circuits)

8. The two winding transformer and the autotransformer of the circuit shown in Figure are ideal. Determine the conducting and transformed currents of auto transformer. N1=200 NBc=20 N2=100 NBA=30 f 10A 200 V 50,Hz N1 : N2 lllll