I Patented DeL-3D, |902. E. ADNDLD, D. SQBDADSTAD D .L -L.. LA coun.

METHOD 0F lGENERA TLND INDEPENDENT ELECTRIC cuN'DE'NTs. (Aplication med Jan. 1a, 1992.)

(No Model.)

inventan? UNITED STATES PATENT OFFICE.

ENGELBERT ARNOLD, OLE s'IvERT ERAGSTAD, AND JENS LAssEE` lLA COUR,

OF KARLSRUHE, GERMANY.

METHOD OF GENERATING INDEPENDENT ELECTRIC CURRENTS.

SPECIFICATION forming part of Letters Patent No. 717,152, dated December 30, 1902.

A Application tiled January 13, `1902. Serial No. 89.555. (No model.)

To @ZZ whom, it may concern: Be it known that we, ENGELEERT ARNOLD, a subject of the Emperor of Germany, OLE SIVERTBRAGSTAD, a subject of the King of Sweden and Norway, and .TENS LASSEN LA COUR, a subject of the King of Denmark, all residing at Karlsruhe, in the Grand Duchy of Baden, Germany, have invented certain new and useful Improvements in the Method 1o of Generating Independent Electric Currents,

of which the following is a specication..

A system of electrical distribution for simultaneous transmission of currents of different frequencies is protected by American Patents Nos. 645,907 and 647,741, toFreder# ick Bedell. The advantage of this superposing of currents of diderent character is thoroughly illustrated in our application for Patent, Serial No. 41,630, filed Decemberv 3l, zo 1900; but this system of Bedell-has the disadvantage that the introduced alternating currentsustains in the windings of the transformers or choking-coils a great drop of potential on account of self-induction. The following-described method will obviate this disadvantage, because thereby electrical currents of different character are introduced in one and the same wire not by conduction, but by induction. This is accomplished by superposing magnetic fluxes in one and the same alternating-current ar-v mature. Moreover, the additional advantage is gained that the same generator-armature can be simultaneously employedfor generating the superposed alternating current of dierent character.

Figure l is a diagrammatic representation of an embodiment of the invention. Fig. 2 is a diagram showing the wave. Fig. 3 is a with one or two primary inductive windings diagrammatic representation of a moditica and with only one induced (secondary) winding. Similarly, as in one and the same winding of a transformer two totally-independent electromotive forces of different frequencies 5 5 by means of a suitable arrangement of two primary inductive windings can be induced,

so it is also possible in the same armaturewinding of an al ternating-current generator byA means of a proper arrangement of two sys- 6o tems of field excitation to induce independent. polycyclic currents. The IL-fold harmonies of an n-phase stai-system all iiow similarly through all n phases from or to the neutral. point, and therefore possess in relation tothe fundamental wave the same properties as do the independent polycyclic currents inrelation to each other. For that reason the triplel harmonic of the main currents of a three-phase generator, for example, can be 7o conveniently used as superposed current, because then the generating of both kinds of currents can occur in the same three-phase armature-that is to say, instead of only one pole system two such are employed, whereof one possesses threefold the number of poles of the second. These two pole systems,wh0se polarity is denoted by N and S, disposed as in Fig. 1, in juxtaposition on the same polewheel, can be excited independentlyor si- 8o multaneously, as in-a homopolar (unipolar) generator. .By this means, through superposition of the two induced electromotive forces, as in the arrangement shown in Fig.

2, the resulting wave y, Fig. 2, is obtained, which also would be yielded if thetwo'pole fields were superposed one above the other, forasmuch as both pole systems are pushed one into another, so that every third pole of Vthe system with threefold number of poles 9o falls together with a main pole ofthe same polarity, as illustrated in Fig. 3. Fig. 4 shows the diagram of the armature-coil connections in the generator, Fig. 3. Through using theV triple harmonics as super-posed current in the manner indicated by Fig. 2 thp maximum induction in the transformers is lessened by means of the superposed current,

so that the hysteresis loss of the same will be lowered, although the total output is inroo creased. It is possible, for example, to .use twenty-five periods for driving motors and y about seventy-five periods for lighting. Inv

4.one pol this .Way the transformers will be correspond-` ingly. sm aller and at the same time/che motors can be better and more cheaply'constructed.

lVere the two pole systems thus superposed lone above the other, as shown in Fig. 5, 'the' corr-esp wading eld Z couldbey obtained with tem ,suitable notches being placed 1 in the n ddle of the broad pole-pieces.

, Ature-winding;

tained by specially-constructed coils which are Wound previously Onav former and then placed on the armature.

What We claim as our invention, and desire' to secure by Letters Patent, is-.-

In a system offelectricall distribution for V the simultaneous transmission of alternating i electrical currents of diierent character, the

'method of the simultaneous generation of a polyphase andav-single-phase current` in one and the same armature-windin g, whereby the single-phase current is of a. frequency, which is a multiple' of that of the polyphase current, and which is used as the superposed current,

which method consists in 'the operation oftwo pole systems on one armature,l of which pole systems the rst possesses a number of poles corresponding to the frequency of' the polyphase current, while the second possesses a number of poles corresponding to the fre'- -quency of the-superposedcurrent, which pole systems are so arranged vrelatively to each other, that ineach phasejof thefarmature eleetromotive forces are induced, which pos- Sess thesame Wave form, as'if both polersystems-Were arranged sideby side. K

In testimony whereof We have signed your namesto this specification in the presence of 'two subscribing witnesses.' A'

' 4ENGELBERT ARNOLD.

OLE 'SIVERT- BRAGSTAD. .TENS LASSEN- LA COUR.

AWitnesses:

JACOB ADRIAN,

H. W. HARRIS.