A3 φ, 10 kVA, 220 V, four-pole, 60 Hz, star-connected synchronous machine has negligible stator winding resistance and a synchronous reactance of 6 ohms per phase at rated terminal voltage. The machine is first operated as a generator in parallel with a 3φ, 220 V, 60 Hz power supply. (a) Determine the excitation voltage and the power angle when the machine is delivering rated kVA at 0.8 PF lagging. (b) If the field excitation current is now increased by 20 percent (without changing the prime mover power), find the stator current, power factor, and reactive kVA supplied by the machine.

A 8 pole wave wound dc shunt generator runs at a speed of 900 rpm, has an armature and shunt field resistance of 0.7 N and 300 N respectively. The armature has 960 conductors and flux per pole is 0.057 Weber. If the lamp load connected has a resistance of 60 2, determine (i) Generated EMF, (ii) Total Resistance, (iii) Armature Current, (iv) Terminal Voltage. Generated EME (Eg) Total Resistance (Rt) Armature Current (la) Terminal Voltage (V)

A short shunt compound generator delivers 150A at a terminal voltage is 230V. The shunt field current is 2.5A. The resistances of the armature, series field and diverter are 0.032-ohm, 0.015 ohm and 0.03 ohm, respectively. Calculate the electrical efficiency of the generator at this load.

A 8 pole wave wound dc shunt generator runs at a speed of 1450 rpm, has an armature and shunt field resistance of 0.7 Q and 240 Q respectively. The armature has 910 conductors and flux per pole is 0.115 Weber. If the lamp load connected has a resistance of 20 0, determine (i) Generated EMF (ii) Total Resistance (iii) Armature Current (iv) Terminal Voltage.

A 3-phase, 2000 kVA, 11 kV, 1800 rpm synchronous generator has a resistance of synchronous reactance of 15 ohms per phase. (a) The field current is adjusted to obtain the rated terminal voltage at open circuit. i. Determine the excitation voltage Ef ii. If a short circuit is applied across the machine terminals, find the stator current. (b) The synchronous machine is next connected to an infinite bus. The generator is made to deliver the rated current at 0.8 power factor lagging. i. Determine the excitation voltage Ef ii. Determine the maximum power the synchronous machine can deliver for the excitation current of part (b). Neglect Ra.

In the DC shunt generator, the induced voltage in idle operation is 127V. Output voltage when loaded it is 120V. Calculate the load current if the field winding resistance is 15 Ohms and the industrial resistance is 0.02 Ohms.

A wave wound armature of an eight-pole generator has 06 slots. Each slot contains 16 conductors. The voltage required to be generated is 300 V. What would be the speed of coupled prime mover if flux per pole is 0.05 Wb.If the armature is rewound as duplex lap wound machine and run by same prime mover, what will be the generated voltage.

Q5) A two-pole dc generator has an armature containing a total of 400 conductors connected in two parallel paths. The flux per pole is 400 mWeb, and the speed of the prime mover is 30 RPM. The resistance of each conductor is 0.001 ohm, and the current-flowing in each conductor is 10 A. Calculate terminal voltage of the generator.

A 2 pole wave wound dc generator has 44 slots, each slot having 20 conductors. The flux/pole is 0.018 weber. At what speed the armature be rotated to get an induced emf of 220 V. What will be the induced emf developed if the armature winding is lap connected and runs at the same speed. Speed Generated Emf when lap connected

solve D and E.