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

(i) Incandescent lighting and heating 80 kW at unity pf;

(ii) Fluorescent lighting 60 kW at 0.9 pf lagging;

(iii) Navigation aids and miscellaneous 45 A at 0.85 pf lagging;

(iv) 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)