. Hawkins electrical guide. Questions, answers & illustrations; a progressive course of study for engineers, electricians, students and those desiring to acquire a working knowledge of electricity and its applications; a practical treatise. FlCS. to 1,244.—Various forms of pressure or current waves. Figs. 1,241 to showthe general shape of the waves produced by some alternators used largely for lightingwork and having toothed armatures. The effect of the slots and shape of pole pihere very marked. Fig. 1,244 shows a wave charactcristu of lam ;. tuned for power transmission and havin
. Hawkins electrical guide. Questions, answers & illustrations; a progressive course of study for engineers, electricians, students and those desiring to acquire a working knowledge of electricity and its applications; a practical treatise. FlCS. to 1,244.—Various forms of pressure or current waves. Figs. 1,241 to showthe general shape of the waves produced by some alternators used largely for lightingwork and having toothed armatures. The effect of the slots and shape of pole pihere very marked. Fig. 1,244 shows a wave charactcristu of lam ;. tuned for power transmission and having multi-slot or distributed win.!. ALTERNATING CURRENTS 1,017 Wave Form.—There is always more or less irregularity inthe shape of the current waves as met in practice, dependingupon the construction of the alternator. The ideal wave curve is the so called true sine wave, and isobtained with a rate of cutting of lines of force, by the armaturecoils, equivalent to the swing of a pendulum, which increases NO. I. no. Z Figs. 1,245 and 1,246.—-Resolution of complex curves into sine curves. The heavy curve canbe resolved into simpler curves A and B sho^vn in No. 1, the component curves A andB have in the ratio of three to one; that is, curve B has three times as many periods persecond as curve A. All the curves, however, cross the zero line at the same time, and theresultant curve, though curiously unlike either of them, has a certain symmetry. In Xo. 2the component curves, besides having periods in the ratio of three to one, crosd-the zeroline at different points. The resultant curve produced is still less similar to its components,and is curiously and unsymmetrically humped. At first sight it is difficult to beKeve thatsuch a curious curve could be resolved into two such simple and symmetrical ones. Inboth figures the component curves are sine curves, and as the curves for sine and cosinefunctions are exactly similar in form, the simplest supposition that can be made for
Size: 1932px × 1293px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookidhawkinselect, bookyear1914
