Twentieth century hand-book for steam engineers and electricians, with questions and answers .. . figure 72. of a rotary converter it can be converted into directcurrent. Rotary transformers which transform the alternatingcurrent to a direct current are simply alternating cur-rent motors connected to direct current these machines are mounted on the sameshaft; sometimes they are belted together, and in somecases the same windings are used for both machines; acommutator being mounted at one side of the armature ELECTRICITY FOR ENGINEERS 129 from which direct current is taken wh
Twentieth century hand-book for steam engineers and electricians, with questions and answers .. . figure 72. of a rotary converter it can be converted into directcurrent. Rotary transformers which transform the alternatingcurrent to a direct current are simply alternating cur-rent motors connected to direct current these machines are mounted on the sameshaft; sometimes they are belted together, and in somecases the same windings are used for both machines; acommutator being mounted at one side of the armature ELECTRICITY FOR ENGINEERS 129 from which direct current is taken while the alter-nating current is taken into the armature on a pair ofcollector rings on the opposite end of the shaft. InFig. 72 is shown a view of a rotary transformer wherethe alternating current is taken in at the right, anddirect current taken off at the commutator on the single phase we understand that the current flowsout, gradually increasing in strength, then dying awayand reversing in direction and again increasing anddying away. This action is shown by the curve in. figure 73. Fig. 73. Although the single phase alternating cur-rent system is in advance of the direct current systemfor electrical power transmission, because permittingelectrical power to be transmitted long distances athigh potential, which can be readily increased orreduced by means of transformers, the single phasesystem is limited by the difficulty in obtaining a satis-factory self starting motor; therefore the use of thesingle phase current has been confined almost entirelyto transmitting current for lighting. The developmentof the polyphase (two phase_ and three phase) alter- 130 ELECTRICITY FOR ENGINEERS nating systems possess all the advantages of the singlephase system and at the same time permits the use ofmotors having not only most of the valuable featuresof the continuous current motors, but also some advan-
Size: 2249px × 1111px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpu, booksubjectsteamturbines
