US698244A - Compensation of generators or motors. - Google Patents

Description

No. 698,244. Patented Apr. 22, I902.

I F. G. BAUM.

COMPENSATION OF GENERATORS OB MOTORS.

(Application filed Aug. 30, 1901.

(No Model.)

HIIHHI WITNESSES: w 4.

NrrED STATES ATFENT OFFICE;

FRANK G. BAUM, OF STANFORD UNIVERSITY, CALIFORNIA, ASSIGNOR TO STANLEY ELECTRIC MANUFACTURING COMPANY, OF PITTSFIELD, MAS- SACHUSETTS, A CORPORATION OF NEW JERSEY.

COMPENSATION OF GENERATORS OR MOTORS.

SPECIFICATION forming part of Letters Patent No. 698,244, dated April 22, 1902.

Application filed August 30, 1901. Serial No. 73,818. (No model.)

To aZZ whom, it may concern.-

Be it known that I, FRANK G. BAUM, a citizen of the United States, residing at Stanford University,California, (post-office address the same,) have invented certain new and useful Improvements in the Compensation of Generators or Motors, of which the following is a full, clear, and exact description.

My invention relates to compensation of to generators or motors, and has for its object to provide an improved means for compensating an alternating-current generator or motor for various changes in loads, both inductive and non-inductive.

r5 The following is a description of a system embodying myinvention, reference being had to the accompanying drawings, in Which Figure 1 shows the system diagrammatically, Figs]? and 3 being diagrams illustrating certain actions that take place.

In the drawings, A represents the coils of a two-phase alternating-current generator; N and S, its two field-magnet poles; B, their energizing-coil, and c c c c the collecting-rings,

from which the current is led to the Workcircuits D D.

E is the armature-coil of an exciter, supplying, through its commutator F and brushes ff, a current to the energizing-coil B.

G is the field-coil of the exciter field-magnet.

H is the field-coil of the compensator fieldmagnet I.

J is the compensator armature-coil, which is connected at one end to a collecting-ring 7c and at the other end to the conducting-seg ments Z Z, on which the commutator-brush L bears. Connected to the brush L is a second brush M, which bears upon conducting-seg- 40 ments m m, alternating with those marked Z Z and connected electrically to the ring 70, on which bears the brush K. The brush K is connected to one commutator-brush f of the exciter, the compensator-brushes M L being connected to one terminal of the exciter fieldcoil, the other end of which is connected to the exciter-brush f.

O is an ammeter, and Vis a voltmeter, for determining the indications as to current and 5 voltage, and P P are translating devices.

The compensator armature and commutafor are mountedon the shaft R of the generator A, which carries the collecting-rings c c c c, the compensator armature-coil being in the same polar relation as is the main-generator armature-coil, that supplies current to its field-magnet.

Because the compensator field-magnet has an alternating magnetizing system corresponding in phase to the current of the main 6o generator and the compensator-armature rotates synchronously there is in the compensator-armature an electromotive force of twice the frequency of the current of the main generator. This is indicated in Figs. 2 and 3, in which T indicates the current of the main generator, andt the electro motive force of the compensator-armature. The segments Z Z of the compensator-commutator are so arranged that when there is ninety degrees lag in the work-current in the circuit D they will coincide with a complete half-period of the compensator electro notive force, so that the upper halves of each cycle are taken off and impressed upon the circuit of the exciter field-coil. This is representedin Fig. 2. If, however, there is a lag of any less amount in the work-current, the upper part of a cycle by that much does not coincide with the segments Z and part of an upper half and part of a lower half is impressed upon the exciters energizing-circuit, as represented by the shaded portions in Fig. 3, the parts corresponding to the lag or lead present. In this way the eXciter responds to any lag in the work-circuit and the lag is duly compensated for. The increased current in the main D due to an increase of load compensates for any tendency toward a drop because of such increased load.

Since the armature-coil of the compensator is in circuit only one-half the time, it is necessary to provide means for connecting the brushes, so as to keep the exciter field-circuit complete at othertimes. This is done by the 5 segments m m, which slightly overlap segments Z Z and are connected to the ring k. When the brush M is upon a segment m, a connection is formed directly between the compensator-brushes. 1 oo In order to make it unnecessary for the whole Work-current to go through the com pensator field-coil II, I provide a shunt U with a means for adjusting the same, so that its time constant shall be the same as that of the coil H. In this Way the lag in II will always be the same as the lag in the undivided main.

One of the advantages of my system is that by causing the compensator to act upon the exciter it is not necessary to apply a compound winding to the main-generator magnet, which is expensive and difficult. Furthermore, it is particularly useful where several machines are to be compensated, since the current from the single exciter can be passed through all the field-magnets, so that they will all be compensated and can be compensated When in parallel and for varying power factors. A similar arrangement can be used with motors.

Vhat I claim is 1. In a system of distribution the combination of an alternatirig-current generator, an exciter therefor, a compensator energized by the alternating current in the main-generator circuit leading to the translating devices and energizing in part the field-magnet of the exciton 2. In a system of distribution the combination of an alternating-current generator, an exciter therefor, and a compensator energized by the alternating current in the main-generator circuitleading to the translating devices, said compensator being in series With the armatures and field-coil of the exeiter.

3. In a system of distribution by alternating currents, a compensator consisting of a field-magnet energized by the alternating current in the main leading to the translating devices, an armature rotating relatively thereto, synchronously with the main generator and a rectifying-con1mutator, said compensator supplying current to the field-magnet of an exciter for the main generator.

4. In a system of distribution by alternating currents, a compensator consisting of a field-magnet energized by alternating currents in the main leading from the main generator to the translating devices, an armature rotating relatively thereto, synchronously with the main generator and a rectifyingcommutator, having the conducting-segments corresponding to one-half of each period removed.

5. In a system of distribution by alternating currents, a compensator consisting of a field-magnet energized by the alternating current in the main leading to the translating devices,an armature rotating relatively thereto, synchronously with the main generator and a rectifying-commutator, having the conducting-segments corresponding to one-half of each period and means for automatically shunting the brushes thereof when they are not upon the conducting-segments of the commutator.

Signed at Butte, Montana, this 29th day of July, 1901.

FRAN K G. llrll TM.

\Vitnesses:

PERCY l3. Dawson, RALPH Dawson.

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