Theory and calculation of alternating current phenomena . he magnetic flux per pole = $, the number of turns in seriesper circuit = n, the frequency = /, the between anytwo collector rings is E = V2 tt/ 2 n^ 10-8, since 2 n armature turns simultaneously interlink with themagnetic flux, $. The per armature circuit is e = V^7r/n$10-8; hence the between collector rings, as resultant of , e, displaced by 60° from each other, is E = e V3 = V2 tt/VS w$ 10-8, 376 AL TERN A TING-C URREN T PHENOMENA while the same was found from the number of turns, themagnetic flu
Theory and calculation of alternating current phenomena . he magnetic flux per pole = $, the number of turns in seriesper circuit = n, the frequency = /, the between anytwo collector rings is E = V2 tt/ 2 n^ 10-8, since 2 n armature turns simultaneously interlink with themagnetic flux, $. The per armature circuit is e = V^7r/n$10-8; hence the between collector rings, as resultant of , e, displaced by 60° from each other, is E = e V3 = V2 tt/VS w$ 10-8, 376 AL TERN A TING-C URREN T PHENOMENA while the same was found from the number of turns, themagnetic flux, and the frequency by direct calculation to beequal to 2 e; that is, the two values found for the same the proportion ?\/^:2 = 1 This discrepancy is due to the existence of more pronouncedhigher harmonics in the wave e than in the wave E = e X a/Sjwhich have been neglected in the formula e = \/2 7r//i* 10-^ Hence it follows that, while the between two collectorrings in the machine shown diagrammatically in Fig. 188 is only. 1S8.—Three-phase star-connected alternator. e X s/S, by massing the same number of turns in one slotinstead of in two slots, we get the 2 e, or per cent,higher , that is, larger output. It follows herefrom that the distorted wave of a unitoothalternator is produced by lesser magnetic flux per pole—that is,in general, at a lesser hysteretic loss in the armature or at higher EFFECTS OF HIGHER HARMONICS 377 efficiency—than the same effective would be producedwith the same number of armature turns if the magnetic dispo-sition were such as to produce a sine wave. 256. Inversely, if such a distorted wave of is impressedupon a magnetic circuit, as, for instance, a transformer, the waveof magnetism in the primarj will repeat in shape the wave ofmagnetism interlinked with the armature coils of the alternator,and consequently with a lesser maximum magnetic flux thesame effective counter w
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectelectriccurrentsalte
