Determine the main dimensions and Turns per phase (T ph )of 1 3000 kVA 6.6 kV, 50 Hz, 187 r.p.m., 3-phase, star connected alternator. Assume average flux density 0.58 Wb/m², ac = 35000. Assume pole arc/pole pitch = 0.7.

In a Three-phase alternator, a given field current produces an armature current of 250 A on short-circuit and a generated e.m.f. of 1500 V on open-circuit. Calculate the terminal p.d. when a load of 250 A at 6.6 kV and 0.8 p.f. lagging is switched off. Calculate also the regulation of the alternator at the given load.   Subject: Electrical engineering

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A four pole, 1200 rpm DC lap wound generator has 1520 conductors. If the flux per poles is 0.01 Wb. Find the generator emf ?

A three-phase star connected alternator has 6 poles and must give an f.e.m. 380 V at 50 Hz. The stator has 3 slots per pole and phase and 4 conductors per groove. Calculate: a) r.p.m. to which the rotor must rotate; b) the maximum flow per pole if it has a sinusoidal distribution. NOTE: The coils are diametrical pitch.

Using logic gates, draw a logic circuit for adding and subtracting numbers (numbers converted to formula 01) where the input is by switches and the output is connected to Segment ships to display the result of the addition and subtraction process, the circuit is 4 bits.

18. The speed at which a 6-pole alternator should be driven to generate 50 cycles per second is. (i) 1500 r.p.m. (ii) 1000 r.p.m. (iii) 500 r.p.m. (iv) none of the above

Alamouti scheme is an example of  A. Space time coding B. MIMO C. None of these

There are 144 slots in a 3-phase, 16-pole, 50 Hz., star connected alternator. There are 4 conductors in each slot and all the conductors in a phase are connected in series. Coil span is 1500 electrical and the flux per pole is 0.05 Weber sinusoidallly distributed. Calculate the emf induced per phase.

A 6 pole, delta connected three-phase alternator having 144 slots is wound using double layer lap coils having 7 turns per coil. The coil has 16 / 24 pitch. The flux per pole is 7380000 maxuells. If the alternator is driven at a speed of 700 rpm, determine the total line-to-line generated voltage.