Two star-connected alternators supply a load of 3MW at 0.8 p.f. lagging, Line voltage being 3.3kV . The synchronous impedance per phase of first machine is (0.25 + j5) Ω and of second machine is (0.3 + j 13) Ω. The excitation of first machine is adjusted so that it delivers 160A at a lagging power factor and the input to prime movers of each machine is set in such a way that load is shared equally between the machines. Determine the current, power factor, induced e.m.f. and load angle of each machine. Operating power factor of one alternator is 0.8.
Synchronous Generator
In comparison to an asynchronous generator, it is a machine where the rotor speed is equal to the rotating magnetic field produced by the stator, i.e., mechanical speed is equal to the electrical speed, thus called synchronous, and not asynchronous.
Salient Pole Rotor
Salient pole rotor includes a large number of exposed poles mounted on a magnetic wheel. The construction of a bright pole is as shown in the image on the left. The proposed poles are made of metal laminations. The rotor winding is provided on these poles and is supported by pole shoes.
Two star-connected alternators supply a load of 3MW at 0.8 p.f. lagging, Line voltage being 3.3kV . The synchronous impedance per phase of first machine is (0.25 + j5) Ω and of second machine is (0.3 + j 13) Ω. The excitation of first machine is adjusted so that it delivers 160A at a lagging power factor and the input to prime movers of each machine is set in such a way that load is shared equally between the machines. Determine the current, power factor, induced e.m.f. and load angle of each machine.
Operating power factor of one alternator is 0.8.
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