Answer Posted / ashish

In Electrical Generation plants, the generation voltage will
be in the range between 11kV and 33kV. Generator designers
wishes to generate the electricity at high voltages as
possible to limit the stator current required to achieve the
desired output. But certain technical and economical
problems will arise which results in designing the generator
for particular voltage and current ratings.
• Low voltage generation for particular power level (say
500MW) requires large size of the stator conductors as huge
currents flow through the stator because of low voltage. (
Any current carrying conductor size is decided by the amount
of current flowing through the conductors). Thereby increase
in the cost and size of the machine takes place.
• On the other hand, increase of the machine voltage
significantly beyond the minimum necessary value results in
more insulation required on the generator stator windings,
thus increasing its size and cost.
Therefore an optimum value of Voltage and Current values are
attained for designing the generator considering the cost
and size factors of the generator.
Example:
660 MW generation plant usually operate at 23.5 kV with line
currents of about 19 000 A at 0.85 power factor.

What will be the effect of circulating current in HT xlpe cable when both the armour ends are grounded. Will the termination fils after some time in case of 33 kv supply.

2121

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I am getting above 60 V as open delta voltage against single phase unit ICT at tertiary delta formed and ICT getting trippped on NDR. ICT tested and found in order. PTs provided on tertiary are tested and in order. what may be the reason?

1854

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What happens to voltage when current through the inductor is constant?

1195

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Differnce between negative Pahse SequenceFunction and unbalance Function?

1793

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1)we have 1000 cfm Blower,Dia-1Mtr,Velocity of air 94 m/s 2)We have Natural Air velocity 94m/s 3If i Put Wind Mill in natural air ,speed is 94m/s Then it will generate Assume 100kw 4)If i put same wind mill across the Blower,air speed is same 94m/s now the Question is Will it generate 100 kw?

2049

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I have one ct of ratio 3000-2000/1 Amp its knee point voltage mentioned on name plate is 500-333/30mA-50mA at Vk/2. in secondary box there is three terminal named 1S1, 1S2, 1S3 then on which terminal obtained the knee point voltage ie 1S1-1S2 OR 1S1-1S3 & also specify the knee point voltage for the ratio 3000 from name plate.

2484

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my bachelors was done with EEE now i got admit in NU with CS as course. how to answer this qns 1) why u choose cs? 2) why u changed from eee to cs

1842

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calculate external resistance values to add to the rotor of a slip ring induction motor. STATOR- 415 V, 3 phase delta, 1100 A, 50 Hz, 1490 rpm, pf 0,86 ROTOR - 660 V, 590 A, 50 Hz. STATOR current at each steps STEP1-600A,STEP2- 800A,STEP3-1000A,STEP4-1100A.

3620

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Why in power plant projects we see DOL starting method used for motors upto 160 kW instead of star delta method

1903

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Pl. brief about break-down maintenance of machine tool.

1856

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what is the difference between 4pole & 6pole DC Motors & give advantage ?

1944

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Please clarify, 1. Is it required to lay two runs of GI wire along with Armoured LT cable if it is laid between one big mains (63Amps TPN SDF) to small main (32A TPN SDF) with proper glanding termination? 2. If the armoured cable with proper glanding is laid from DB to CNC machine, is it required to run two runs of body earthing to the Machine from DB? 3.If the armoured cable with proper glanding is laid from Substation to Hangar, distance is approx. 100 mtrs, is it required to do earthing at shop area though the primary termination at substation is earthed through gland.

2084

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DG cranking voltage?

4813

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How could a garment factory benefit from renewable energy

2823

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how much allowable resistance that can be difference in motor all coils?

2411

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