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A 450-V-rms, 50-Hz eight-pole delta-connected synchronous motor operates with a developed power (including losses) of 150...

A 450-V-rms, 50-Hz eight-pole delta-connected synchronous motor operates with a developed power (including losses) of 150 kW and a power factor of 0.9 lagging. The synchronous
reactance is Xs = 1.6 ?. How much must the field current be increased to produce 100 percent power
factor? Assume that Br is proportional to If with no magnetic saturation.

(I would be very grateful if you could write neatly :) )

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