Answer / abdul hameed

first we need DC current in the rotor second we need AVR this device controlled the the voltage which feeding the rotor.this
method is suitably for brush and brush less generator

Answer / vinod

EXTERNAL DC SOURCE

Answer / siddhu

In an alternator the rotor acts as a field winding it produces rotating flux when excited with dc current by an external dc source when this flux cuts the armature, current is induced in it.

What_is_mean_by_negative_dc_voltage? why we use -48v except +48v in DC power supply systems.

2 Answers   APEL, BSES,

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How to decide the input and output circuit breaker for a 1600kva transformer.Is there any calculation is involved.

5 Answers  

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WORKING PRINCIPLE OF HALOGEN LAMP & MEQUERY LAMP

1 Answers  

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Can VFD step up to 60 Hz if it is designed to receive 50 Hz input?

3 Answers  

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1 hp single phase motor is more likely to get hot thsn inone hp 3 phase motor its true or false? If true why?

3 Answers   Focus, Focus Energy,

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for 5KW resistive load can anyone please suggest me whether to go for UPS/Inverter or Generator depending upon cost calulations

0 Answers  

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how can H.V busbar in a powerstation can be protected?

1 Answers   Unitech,

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How can calculate the efficency of the rectifier. input 240V AC, current 5 amps,P.F 0.98, Output is 54 V DC,62.6 A.

10 Answers  

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How open delta used for protection?

4 Answers  

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how to calculate no load losses units comsumed by transformer

2 Answers   MRF,

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How can we explain that what is the power factor?

5 Answers  

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What is meant by Floating Neutral? how to prent

7 Answers  

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