No. 12,793. REISSUED MAY 12, 1908. G. A. WELLS, JR. APPARATUS FOR THE REGULATION OF ELECTRIC SYSTEMS, APPLICATION FILED JUNE 22, 1906,

UNITED STATES PATENT OFFICE. y GEORGE A. WELLS, J.R., OF NEW YORK, N. Y. APPARATUS FOR THE REGULATION OF ELECTRIC SYSTEMIS. No. 12,793. Specification of Reissued Letters Patent. Reissued May 12, 1908. Original No. 821,909, dated May 29, 1906, Serial No. 180,536. Application for reissue filed June 22, 1906. Serial No. 322,982. To all whom it may concern: taken in connection with the accompanying Beit known that I, GEORGE A. WELLs, Jr., drawing, forming a part hereof, and in which a citizen of the United States of America, and I have illustrated diagrammatically certain a resident of the city, county, and State of apparatus embodying specific features of my New York, have invented certain new and invention. 60 useful Improvements in Apparatus for the In the drawing the main source of power is Regulation of Electric Systems, of which the represented as a generator B, connected in following is a specification. the customary manner to the working or line The object of my invention is to relieve conductors 1 and 2. The compensating elec O electrical systems and apparatus from the tric A is arranged in parallel with 65 widely-varying stresses incident to or caused the generator B by means of the line conduc by the changing demands of a fluctuating tors 1 and 2 and the cross-conductors 3 and 4. load-such, for instance, as exist in different This compensating machine Amay be of any degree in all systems for electric-power dis suitable or well-known character. As shown 5 tribution of whatsoever nature. in the drawing, its field is provided with two 70 Varying demands for power are perhaps coils A and A, the first of which is connected most commonly manifest in electric-railway to the line conductors 1 and 2, while the practice of the present day, and the following latter is a Series winding and is connected by described improvements are applicable to the conductor 4 to the C, hereinafter such a system, although I do not confinemy to be referred to. The two coils oppose each 75 invention specifically to such use, as the other in varying degree, so that the motion is principle is susceptible of being adapted to differential. The of the compen any electric circuit. sating machine is provided with a fly-wheel The gist of my invention resides in the em. W to store in the form of 25 ployment of devices whereby under normal momentum and subsequently to release it as conditions the apparatus is electrically oper electric energy. ated so as to acquire mechanical energy, In order to increase the efficiency of the which is reconverted into electric power as compensating machine A and to act as a gov occasion demands. I employ in connection ernor therefor, I employ a booster C in series 30 with such apparatus governing mechanism thereWith and in multiple with the generator 85 to increase the sensitiveness thereof, so that B through the line conductors 1 and 2 and it may respond more readily to the demands the cross-conductors 3 and 4, as plainly upon it. Specifically, I E to use an elec shown in the drawing. The booster may be trodynamic or dynamo-electric machine pro of any desired form to secure the desired re 35 vided with a fly-wheel or other considerable Sult-namely, to increase the sensitiveness 90 mass connected to a rotating part and in of the compensating machine A and to act as combination there with a booster to increase a governor therefor, or, if desired, other its sensitiveness, and hence its speed of ac equivalent apparatus might be substituted tion, in adapting itself to the varying stresses without departing from the spirit of my in 40 of the system. This compensating machine vention. As shown in the drawing, I have 95 is designed to run as a motor when the load illustrated a form of booster similar to that is at its mean, and by reason of the attached resented in the Letters Patent to J. B. Entz, mass or fly-wheel considerable momentum is o. 625,098, May 16, 1899, the field of the acquired thereby. When the work becomes said booster being so wound and connected 45 excessive or the supply of electric power di to the main circuit as to render it respondent OO minishes, the acquired momentum causes to the different conditions of load and supply. the compensating machine to run as a dy As shown, the field of the booster is pro namo. While the employment of the com vided with coils 5, 6, and 7, the coil 5 being pensating machine alone might in itself ma composed of comparatively fine wire of many 50 terially aid the constancy of the power, the turns, and the coils 6 and 7 are composed of 05 addition of the booster serves to assist its comparatively few turns of coarse wire. The delicacy. - - coil 5 is connected with the circuit so as to The nature, characteristic features, and eXcite the field in one direction, and the coils scope of my invention will be more fully 6 and 7 are connected with the circuit so as Resto from the following description, to excite the field in the opposite direction, so O

ge 12,793 that the effect of coils 6 and 7 is to oppose the the latter to govern the of the com effect of coil 5 in respect to magnetization pensating electric machine by a change of of the field. The coils 6 and 7 are in series current in the generator-circuit-that is to relation with respect to the conductor 2. say, in the circuit of the working conductors However, one of them, 7, is led off from the on the generator side of the compensating O conductor 2 on the generator side of the electric-machine conductors 3 4-so that if, union of the compensating-electric-machine due to imperfect regulation by the coil 6, an conductor 4 with the working conductor 2, increase or decrease of load comes on the gen and the other coil 6 is led off from the con erator B and must pass through the coil 7 O ductor 2 on the service side of the union of an increase of current through the coil 7 op 75 the compensating-electric-machine conduc erates to raise the voltage of the booster, and tor 4 with the working conductor 2. The ob therefore tends to increase the discharge of ject of this arrangement will be presently de the compensating electric machine, thereby scribed. The circuit for the coil 5 may be as reducing the increased load that would other 5 follows: from conductor 1 by conductor 8, wise come on the generator. A decrease of through coil 5, and by conductor 9 to conduc current throughout coil 7 operates to decrease tor 2 on the service side of the union of the the voltage of the booster and compensating compensating electric machine with said electric machine, and therefore tends to make working conductor. In this case the coil is the compensating electric machine take more 20 connected across the compensating- from the generator than it would 85 machine terminals. The path through the otherwise do. The action of a change of cur coil 6 may be described as from the conduc rent in the coil 7 is the same as in the coil 6. tor 2, by 10, through coil 6, by 11, back to If the coil 6 works perfectly, the change in conductor 2. The path from coil 7 may be load on the working conductors is compen 25 described as by 12 through coil 7 and by 13 sated by the variation in speed of the com 90 to conductor 2. Under certain conditions of pensating electric machine, and no change of load the coil 5 is balanced by the coils 6 and current occurs through the coil 7 or in the 7, so that the voltage of the booster may be generator. By reason of changes in the con represented as Zero when the compensating dition of the compensating electric machine electric machine, although in motion, is inert the compensation of coil 6 is frequently not 95 in its capacity as a regulator. In the event sufficient and change of current does get of an increased load in the service or working back to the generator. Such current must circuit the coil 6 by its action upon the field pass through the coil 7, which thus adds its of the booster causes the latter to add its governing effect to that of coil 6 and causes 35 voltage to the compensating electric machine the compensating electric machine to ab 100 by the same amount, as it tends to fall by sorb and deliver energy and to keep the load reason of an increased delivery of energy On the generator constant. In order to gov equal in amount to the increase of load on ern the load on the generator by means of a the service-conductors. In the event of a single coil, such as 7, it would have to be of 40 decreased load in the service or working cir exceedingly large size in order to keep the cuit the coil 5 overbalances the coil 6, and its load on the generator constant within rea action upon the booster deducts its voltage sonable narrow limits, because of a small from the compensating electric machine to change of current through it would have to the extent that it will absorb energy from the produce the total regulating effect. How 45 generator equal to the decrease of load on the ever, to only correct imperfections of the coil working circuit, and thus keep the load on 6, due to changes in the compensating-elec the generator constant; but in order for the tric-machine condition, it need be of only whole system to work constant and keep a moderate size. It will be obvious that the constant load on the generator B the voltage connection of such a booster or other govern 50 of the compensating electric machine must ing device to the compensating machine Ain I5 always rise or fall the same amount for a creases the delicacy of the latter and causes given increase or decrease in absorption or it to respond quickly to the various changes delivery of energy. In practice the change in the load equation. in voltage of a compensating electric machine The compensating machine A is construct 55 for a given change in current depends upon ed and wound to generate a counter electro 20 whether the compensating machine is run motive force at its normal speed equaling ap ning above or below its normal speed. There proximately the normal voltage of the main fore under all speed conditions of the com circuit at the average load of the system. pensating electric machine the coil 6 alone, in The fluctuations in load are assumed by the 60 connection with the coil 5, would not effect compensating machine Ain Substantially the 25 the regulation required for keeping the load following manner: When the relation of On the generator constant and causing the power to load is raised above the average, compensating electric machine to compen either by an increase in the former or by a de sate for change of load. The coil 7 by its op crease in the latter, or by both, the excess 65 eration upon the field of the booster causes power through the medium of the booster L30

12,798 B acts immediately to increase the Speed of the windings opposed to the shunt-field and con compensating machine, and the surplus en nected in the main circuit, said booster hav ergy thus available is stored therein in the ing its armature interposed in the electrical form of momentum by means of the attached connection of the compensating electric ma fly-wheel. If now the relation of power to chine with the main circuit. 60 load be brought below the average, either by 2. In a system of electrical distribution, a decrease in the former or by an increase in the combination of a generator adapted to the latter, or by both, the deficiency in energy supply the main circuit with the working cur in the main circuit is supplied by the counter rent, a compensating electric machine em O generated by the com bodying a rotary member, adapted to store 65 pensating machine, which is now run as a dy mechanical energy and Subsequently release namo by the previously-stored momentum in it as electric energy, and having its armature the fly-wheel. It will thus be seen that the connected in multiple with the generator, arrangement described tends to assume and and a booster provided with a shunt-field 5 regulate the fluctuations in the main circuit, with approximately constant , 70 and due to the connection of the governing and a plurality of windings opposed to the apparatus or booster that the sensitiveness shunt-field, and connected in series in the p the compensating machine is materially in main circuit, said booster having its arma creased. ture connected in series with the armature of It will be obvious to those skilled in the art the compensating electric machine. 75 to which the invention appertains that many 3. In a system of electrical distribution, modifications may be made in details without the combination of a generator adapted to departing from the spirit thereof. Hence I supply the line conductors with the working do not limit myself to the precise arrangement current, a compensating electric machine 25 of parts hereinabove set forth, and illustrated having a differential field excitation and 80 in the accompanying drawing. For instance, adapted to store mechanical energy and con my improvement is capable of employment nected with the line conductors, and a in connection with any system of electric dis booster interposed in the connection be tribution however supplied or for whatever tween the said compensating electric ma 30 purpose intended. The compensating ma chine and one of the line conductors and hav 85 chine itself may be of different construction ing a differential field excitation dependent and arrangement and may or may not be pro upon the variations of the working current vided with a fly-wheel, as the construction of and the speed variations of the compensat the machine might be of such a character as ing machine. 35 to enable it to store power without additional 4. In a system of electrical distribution, 90 means, or other devices may be used to the combination with a generator, of com store and preserve the surplus energy, and, pensating mechanism adapted to store me as before stated, the booster may be of any chanical work or energy and subsequently convenient form, or it may be dispensed with release it as electric energy, and means for 40 entirely and other governing apparatus sub increasing the sensitiveness with which said stituted therefor. compensating machine responds to varia Having thus described the nature, construc tions in the working current, said means tion, and operation of my invention, what I comprising an electric machine in circuit claim, and desire to secure by Letters Patent with said compensating machine and having 45 of the United States, is as follows: a differential field excitation which responds LOO 1. In a system of electrical distribution, to variations in the conditions of the com the combination of a generator adapted to pensating machine. supply the line conductors, with the working In testimony whereof I hereunto set my current, a compensating electric machine in hand this 18th day of June, 1906, in the pres 50 electrical connection with the line conduc ence of two attesting witnesses. tors, and adapted to store mechanical energy and subsequently release it as electric energy, GEORGE A. WELLS, JR. and a booster provided with a shunt-field Witnesses: with approximately constant excitation, and A. W. BERNER, 55 provided further with one or more series CHARLEs SCHLOPFER.