TransactionsPublished under the care of the General Secretary and the Treasurer . passes by ± or. foran average voltage E-^^, and is negative for weak voltages (approxi-mately equal to — 1 for E^ in the figure). -— is therefore posi- A2five, but always smaller than 1 for high voltages, zero for the voltage J5i, and negative for the weak voltages. In giving to Ai 676 BOUCHEKOT: VABIATIOyS. a reasonable value, 2, for example, A lies between 1 and 3 forhigh voltages, equal to 3 for the voltage E^, and greater than 3, 5,10 or more, for voltages such as E^ smaller than E^, If we take into ac
TransactionsPublished under the care of the General Secretary and the Treasurer . passes by ± or. foran average voltage E-^^, and is negative for weak voltages (approxi-mately equal to — 1 for E^ in the figure). -— is therefore posi- A2five, but always smaller than 1 for high voltages, zero for the voltage J5i, and negative for the weak voltages. In giving to Ai 676 BOUCHEKOT: VABIATIOyS. a reasonable value, 2, for example, A lies between 1 and 3 forhigh voltages, equal to 3 for the voltage E^, and greater than 3, 5,10 or more, for voltages such as E^ smaller than E^, If we take into account that with motors, when the voltage de-creases more tlian the frequency, the output increases, and viceversa, we see how dangerous it may be in certain cases to onlyconcern ourselves with the fall of voltage at constant speed. Andwe also understand why builders have been led to saturate theiralternators more and more. This saturation, resulting in the re-duction of fall in the actual voltage, kinetic variation included,which occurs when there is an increase of Fig. 3.— Characteristics of alternator working at constant loadindependent of speed. The same observations, with a few variations, might apply tothe continuous-current dynamos which feed motors; but we neednot delay over this point. Compound Alternators. It is not a question here of alternators with revolving fieldframes and collector rings, but of standard compounded alternatorsfurnished with a special exciter, in which the continuous currentis produced by means of alternating currents issuing from thearmature of the alternator, varying in strength with the outputand the cos. f of that output, by the use of a compounded con-verter, or otherwise. We will suppose that in such a system the exciter is always suffi-ciently far from saturation for us to suppose that the currents BOUGHEROT: VARIATIONS. tf77 and flux are proportional, and that stability is obtained entirelyby the saturation of the alter
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