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Q5. A three-phase, 440 V, 60 Hz shaft- generator supplies the following loads:

Incandescent lighting and heating 80 kW at unity pf

Fluorescent lighting 60 kW at 0.9 pf lagging

Navigation aids and miscellaneous 45 A at 0.85 pf lagging

Induction motors 240 kW at 0.8 pf lagging

(a) Determine the total kW, kVAr, kVA and the overall power factor of the ship’s load.(10)

(b) A three-phase synchronous motor which takes 70 kW is now connected to the power system.

Determine EACH of the following:

(i) The required power factor of this motor to cause the shaft generator to operate at unity power factor; (3)

(ii) The current taken by the synchronous motor. (3)