Electrical Engineering Objective Questions { Alternators }

36. The Potier's triangle separates the

37. In a slip test on a salient-pole machine, the emf induced in the field winding is

38. If in a 3-4) alternator, a field current of 50 A produces a full-load armature current of 200 A on short-circuit and 1730 V on open circuit, then its synchronous impedance is

39. For a P-pole machine, the relation between electrical and mechanical degrees is given by

40. El, E3, E5 are the fundamental, third harmonic and fifth harmonic per phase voltage generated in a starconnected alternator. Its line voltage is

41. An alternator has rated field current of 2A. This alternator is developing 200 V at a field current of 1 A at rated speed. If its field current is made 2A at rated speed, then the generated voltage would be

42. An alternator running at 1500 r.p.m. delivers rated current of 30A to a purely inductive load. With the filed current remaining constant, If the speed is reduced to 1000 rpm, the load current becomes

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