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An alternator is supplying a load of 300 kW at 0.6 p.f. lagging. If the power factor is raised to unity, how many more kilowatts can alternator supply for the same kVA loading?

An alternator is supplying a load of 300 kW at 0.6 p.f. lagging. If the power factor is raised to unity, how many more kilowatts can alternator supply for the same kVA loading? Correct Answer 200 kW

P = S cos ɸ

P = 300 kW, cos ɸ = 0.6

S = 300/0.6 = 500 kVA

Now, cos ɸ = 1, S = 500 kVA

P = 500 × 1 = 500 kW

More kilo watts can alternator supply for the same kVA loading = 500 – 300 = 200 kW

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