TransactionsPublished under the care of the General Secretary and the Treasurer . RkLATION of cost to SYNCHBONOtrS ^PKEIX 792 HOB ART: INDUCTION MOTORS. diiction motors and their performance so far as relate^ to the value-5of fl-have been plotted as functions of the synchronous speed for thedesigns for 100 horse-power, 1000 horse-power and 10,000 horse-power, and for , 25 and 50 cycles per second. The cost and ^ curves are placed in parallel columns, to facilitatean understanding of the curves. One fact is very striking, namely, the lower minimum totalworks cost and the larger values of ,
TransactionsPublished under the care of the General Secretary and the Treasurer . RkLATION of cost to SYNCHBONOtrS ^PKEIX 792 HOB ART: INDUCTION MOTORS. diiction motors and their performance so far as relate^ to the value-5of fl-have been plotted as functions of the synchronous speed for thedesigns for 100 horse-power, 1000 horse-power and 10,000 horse-power, and for , 25 and 50 cycles per second. The cost and ^ curves are placed in parallel columns, to facilitatean understanding of the curves. One fact is very striking, namely, the lower minimum totalworks cost and the larger values of , has been taken as depending only upon the brakehorse-power. It would have been more correct and more in accord-ance with the present practice to take a slightly higher outputcoefficient for low periodicities. This would have decreased thecost and slightly increased the dispersion coefficient ( <t) of thelow frequency, as compared with the high frequency .8 r>F ^ .6 .8 2.!\9 Figs. 6 and 6A.â Cueves of cost belatiox. Figs. 6 and 6a, show for the 100-hp, 25-cycle designs, the varia-tion in the total works cost and in ^ with variations in the ratioof ^g to T. It is evident from these curves that it is permissible todepart to a considerable extent from the ratioâ^= as the total works cost will not be increased by any prohibitive amount. On theother hand, we learn from Fig. 6, that the decrease in ^ is very slight for a considerable decrease in â and hence so far as power factor is concerned, one rapidly reaches undesirable dimensions in EOBART: INDUCTION MOTORS. 793 endeavoring to improve the power factor. But especially in smallmotors, one is for this and other reasons obliged to depart wideljfrom the most favorable ratio, so. far as regards minimum cost. In such cases considerably smaller values than the ratio -^= are commonly employed. But for all medium sizes an
Size: 2562px × 976px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookidtr, booksubjectelectricity
