IMPROVEMENTS IN THE METHODS AND APPARATUS FOR DISTRIBUTING AND REGULATING THE TRANSMISSION OF ELECTRICAL POWER
Year: 1881

page_text: LETTERS PATENT to John Imray, of No. 28, Southampton Buildings, in tho
County of Middlesex, for an Invention of "IMPROVEMENTS IN THE METHODS
AND APPARATUS FOR DISTRIBUTING AND REGULATING THE TRANSMISSION OF
ELECTRICAL POWER," A communication from abroad by Marcel Deprez
and Jules Carpentier, both Engineers, of Paris, France,
PROVISIONAL SPECIFICATION left by the said John Imray at the Office
of the Commissioners of Patents on the 24th September 1881.
JOHN IMRAY, of No. 28, Southampton Buildings, in the County of Middlesex.
"IMPROVEMENTS IN THE METHODS AND APPARATUS FOR DISTRIBUTING AND
REGULATING THE TRANSMISSION OF ELECTRICAL POWER." [A communication from
abroad by Marcel Deprez and Jules Carpentier, both Engineers, of Paris, France.]
This Invention relates to means of distributing and regulating the transmission
of electrical power from the source where it is produced to a number of places
where it may be employed. When a number of electric lights or machines are
worked from one main circuit the use or disuse of one or more, affects all the
others. In order to provide against this, instead of connecting each of the lights
or machines directly to the circuit, it is according to this Invention connected to
one of two batteries which has been charged from the main circuit, the other of
the two in the meantime receiving its charge from the circuit so as to be ready for
use when the former is more or less exhausted. In connection with the two
batteries a commutator is provided arranged to connect the circuit with each of
the two batteries alternately, and the other of the two batteries to the light or
machine that is to be worked. In order to diminish the variations to which a
dynamo electric machine is subject when the resistance of the circuit to which it is
connected varies, the machine instead of having its electromagnets excited entirely
from the circuit itself, is according to this Invention arranged so as to have them
partly excited from a source of electricity, which may be of a constant character, or
which may be varied so as to counteract more or less the variations in the circuit.

page_text: Again, instead of exciting the machine by a constant current, it is excited by a
series of intermitted currents, the intermissions being effected by a centrifugal
governor, so arranged that when the speed of the machine increases beyond the
normal rate, the current is arrested and remains arrested until the machine
becomes sufficiently retarded. A governor for this purpose may consist simply of
a contact spring revolving with the machine or in gear with it, the tension of the
spring being so adjusted that when the velocity exceeds a certain limit, the spring
is caused by centrifugal force to leave the contact, and so to intermit the current
which excites the machine. When two machines worked by alternating currents
are connected as a producer and receiver, they necessarily have tho samo speed, and
a resistance applied to the receiver causes a like resistance to the producer. If
therefore one alternating current machine be employed to work a number of
separate machines of like kind in circuit with it, when any of these machines
undergo less or greater resistance the main producing machine is similarly affected,
and it being regulated so as to maintain a velocity constant or nearly so, the
other machines are thus also regulated. When two equal and similar alternato
current machines excited from the same source and moving with the same speed
have their coils passing through the same phases simultaneously, the current
produced by the two is double that produced by either alone. If however the axis
of either be turned more or less round relatively to the other, the produced current
-can be reduced-to-any extent, or it.can be rendered nil when the phases of the coils
in the two machines are opposed to one another. By employing two machines in
this manner for supplying electric lights the production of electricity can be
exactly suited to its expenditure. In order to maintain the electrical production
proportional to the expenditure for working a number of machines, the following
arrangement is according to this Invention adopted-A small machine at the place
of production is employed as an indicator, shewing by its greater or less speed the
greater or less speed of the rest of the machines, with which being on the saine
circuit it necessarily works synchronously. The producing machine can therefore
be less or more excited according to the indications thus given. Instead however
of varying the exciting power of the producing machine by hand, it is varied
automatically by the action of the small machine, which is provided with a
governor and suitable rheostat, so that according as its velocity increases or
diminishes it decreases or increases the supply of electricity for exciting the
producing machine, this supply being taken in whole or in part from another
machine or battery, and being more or less resisted according as the supply to the
producing machine requires to be varied. When electricity of low tension is.
employed to work apparatus distant from the producer, instead of sending it in
quantity by the conductor, it is according to this Invention by means of an
induction coil employed to produce a current of high tension. This current is more
readily transmitted over considerable distances, and when it arrives at its destination
it is inversely, applied to generate by an induction coil a quantity current
for use.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Imray in the Great Seal Patent Office on the 22nd March
1882.
_JOHN IMRAY, of No. 28, Southampton Buildings, in the County of Middlesex.
"IMPROVEMENTS IN THE METHODS AND APPARATUS FOR DISTRIBUTING AND
REGULATING THE TRANSMISSION OF ELECTRICAL POWER." A communication from
abroad by Marcel Deprez and Jules Carpentier, both Engineers, of Paris, France.
This Invention relates to means of distributing and regulating the transmission of
electrical power from the source where it is produced to a number of places where it
may be employed. When a number of electric lights or machines are worked from
one main circuit, the use or disuse of one or more affects all the others. In order
to provide against this, instead of connecting each of the lights or machines directly
to the circuit, it is according to this Invention connected to one of two batteries
which has been charged from the main circuit, the other of the two in the mean-
time receiving its charge from the circuit so as to be ready for use when the former
is more or less exhausted. In connection with the two batteries a commutator is
provided arranged to connect the circuit with each of the two batteries altornately,
and the other of the two batteries to the light or machine that is to be worked.
Fig. 1 shews diagrammatically the above described arrangement of two secondary
batteries in connection with the circuit which are alternately charged with the
current while the other is giving off its charge; M is the electric current generator
from which the circuit X, X, passes to the subscribers, each of which has two
secondary batteries B and B¹ enclosed in a box A into which the current is conveyed
by a branch wire a connected to a commutator that conveys the current alternatoly
to one or other of the batteries. From these the current passes alternately to the
wire f, which conveys it to the apparatus where it is to be utilised. Assuming that
the current X is charging the battery B' while the current is passing from B,
when this current has become weakened to a certain degree the automatic galvano-
meter g acts a commutator, causing the connection to be changed, so that the
current passes from X to B, charging the same, while B' is discharged into f. By
this means it will be seen that a very constant supply of electricity may be
furnished; the quantity of electricity supplied may be registered by any known
form of electric meter. Various arrangements of commutators may be employed
for automatically changing the connections; thus the commutator shewn at Figs. 2
and 3 may consist of a frame carrying two contact springs b, b¹, and two others
insulated therefrom c, c'; to the contact plates d, d, are connected the line wires;
to the contacts e, e¹, are connected the wires of the battery B, and the contacts e³, e³,
es, es, are connected to the battery B'. In the position shewn at Fig. 2 the current
from the line wire is passing to the battery B, and B' is being discharged; when
the frame is moved into the position at Fig. 3 the reverse connections are made.
The same result may be obtained by a circular commutator.
In order to diminish the variations to which a dynamo-electric machine is
subject when the resistance of the circuit to which it is connected varies, the
machine instead of having its electromagnets excited entirely from the circuit itself,
is according to this Invention arranged so as to have them partly excited from a
source of electricity which may be of a constant character, or which may be varied
so as to counteract more or less the variations in the circuit.
In the diagram, Fig. 4, the abcissae represent the time, and the ordinates the
tensions, the curve m, n, o, representing the work in the case where the induction
is entirely in the main circuit, the variations of tension being in this case con-
siderable, but if a permanent excitement bo added, the work of the latter will bo

page_text: represented by a horizontal line m', q, so that the variation in the power is much
less than in the first case.
Again, instead of exciting the machine by a "constant current, it is excited by a
series of intermitted currents, the intermissions being effected by a centrifugal
governor, so arranged that when the speed of the machine increases beyond the
normal rate the current is arrested and remains arrested until the machine becomes
sufficiently retarded.
Fig. 5 shews diagrammatically this mode of working with interrupted currents;
the line O, t, represents the intensity of the current which is first admitted during
the time 1-2, consequently the rectangle represents the work done. The motor
having increased in speed the supply is stopped until the point 3, when the speed
having again diminished the current is again admitted during 3-4, and so on, the
total work performed being the same as though the current had been admitted
continuously with the intensity O, u, and consequently being measured by the
rectangle O, u, v, 10. The automatic production of these interruptions may be
effected by means of a centrifugal governor, thus upon the Siemens' armature of a
motor, Fig. 6, a spring h through which the current is made to pass is fixed at h,
the other end being free and subjected to a regulated tension by a screw i resting
on a contact j. On an acceleration of the speed taking place the spring is acted on
by the centrifugal force so as to remove the screw i from the contact j, whereupon
the current will be interrupted. On the speed becoming again reduced the screw ¿
again makes contact and the current passes again.
When two machines worked by alternating currents are connected as a producor
and receiver, they necessarily have the same speed, and a resistance applied to the
receiver causes a like resistance to the producer. If therefore one alternating
current machine be employed to work a number of separate machines of like kind
in circuit with it, when any of these machines undergo less or greater resistance
the main producing machine is similarly affected and it being regulated so as to
maintain a velocity constant or nearly so, the other machines are thus also
regulated. Thus if a dynamo-electric inachine M, Fig. 7, with alternato currents
have on its circuit X, X, a certain number of electro-dynamic motors M' without
commutators, either in derivation, as at Fig. 7, or in tension as at Fig. 8, all these
motors would move with precisely the same speed as the generator M. It will
therefore be sufficient, whatever be the resistances to which the motors M' are
subjected, that the machine A receive a constant speed in order to make the
machines M work with the same speed, no matter whether one or more be stopped
or put in motion.
This mode of transmisssion of the electric force by means of machines with
alternate currents connected together leads to the consideration of the circum-
stances that may result from the relative positions of the armature coils of the
machines thus connected. If, as in Fig. 9, the two machines so connected are
arranged so that their coils C, C, are in the same position relatively to the
magnets D, D', then if the motor M is not subject to any resistance to be overcome,
the generator M will not produce any current, but nevertheless it will effect the
rotation of M'. To speak more accurately a current is produced, but the notor M¹
produces a reverse current which neutralises that of the generator M. When the
motor M has a resistance to overcome the reverse current is less or ceases, and
the generator will experience the same resistance; but this equality between tho
force generated and that received by the motor only exists when the machines are
in exactly the same relative positions. If, as in Fig. 10, the coil C¹ has a different
position relatively to C this condition does not exist, the relation between the
direct motive force of M and the inverse force of M' varying according to the
extent to which the positions of C and C differ. This fact meets with practical
application in the regulation of machines for electric lights. Assuming two
alternate current machines of identically the same arrangement to be connected
to one and the same axis and placed in the same circuit, then if the fixed parts
constituting the electrical inductors are magnetised in the same manner, the

page_text: current generated by the two machines will be exactly double that produced by.
one only, but if the position of the fixed parts of the second machine be shifted
relatively to those of the first, the current generated will be weaker on account of.
the reverse current generated by the second machine at certain parts of its
revolution, and there will be a position of the fixed parts of the second machine
that will cause the current to be completely neutralised. By this means a new
mode of regulation of the intensity of the current can be obtained.
The motors or electrical apparatus fed from a source of electricity can be either
placed in tension on the circuit, that is, the entire current being made to pass
consecutively through all the machines, or they may be placed in derivation. In
both cases it is sufficient to render the current passing through one of the machines
constant in order to insure that the current passing through all the others shall be
constant, and the fact whether the current is constant or not will be indicated by
the variations of speed to which the said machine is subject. If therefore, as at
Fig. 11, there are soveral motors M either in derivation or in tension on the
circuit X supplied by the generator M, and an indicator motor M³ also fed by the
same current in the same manner and situated at the works be made to overcome
a constant resistance, such as a friction brake F, then if one or more of the
motors M be stopped or started resulting in an increase or decrease of spoed of all
the others, the indicator motor M will also be subject to such increase or decrease,
and these variations in its speed may then be utilised for effecting the corre-
sponding regulation of the electric power furnished by the producer M. For this
purpose the indicator M' is furnished with a centrifugal governor & acting on a
conical clutch and on a rheostat m placed in a secondary circuit x, x, fed by any
electric source, such as a battery or a small dynamo-electric machine n, which
circuit is also connected to the generator M. Thus according as by the variations
in speed of the indicator M² a current of more or less force is sent through the.
secondary circuit, the force of the current passing from the generator M into the.
circuit X, X, will be more or less modified thereby, thus effecting a regulation of
the speed of the motors M¹.
Fig. 12 shews a modification of the preceding arrangement in which the regu-
lator is formed by an electro magnet indicator O placed on the circuit y, y, branching
from the main circuit, as in the case of the motor indicator of the preceding
arrangement; a derivation circuit 2, 2, also supples a small electro-dynainic
machine p. The electromagnet o has an armature q which is always acted upon by
a spring and which carries a block 8 acting as brake to the axis of the machine p.
If the resistance increases in the circuit X, X, a weaker current will pass through
the indicator electro-magnet o, and the spring r in drawing back the armature q
applies the brake 8 so as to stop the small machine p; this consequently offers less
resistance to the current so that the generator M becomes more excited and supplies
an increased current to the circuit X, X. The reverse takes place if, from any cause,
the resistance decreases in the circuit X, X. The tension of the spring ris
regulated at will.
Another mode of conveying an electrical current to a distance with as little loss
of power as possible is based on the following discovery:-When a quantity current
proceeding, for instance, from one or more elements of a Bunsen battery, is passed
through the large wire of a Ruhmkorif's coil, high tension currents are produced
in the small wire which can overcome a large resistance, and can consequently be
conveyed to a considerable distanco without appreciable loss of power. If this
high tension current be then made to pass through the small wire of a second
coil at the receiving station it will induce a quantity current that will have nearly
the same force as the quantity current acting on the first coil, and which can then
be employed as motive power or for other purposes, or the high tension currents
can be employed direct for any purpose for which they are suitable without being
converted into a quantity current. By this means it has been possible to heat to
redness a platinum wire situated at a distance of several hundred thousand yards
by means of two Bunsen elements, whereas it would have required a very great

page_text: number of elements to obtain the same result if the communication between the
platinum wire and the battery had been direct, because the quantity current
rapidly loses much of its energy if a resistance is opposed to it.
Having thus described the nature of the said Invention, and in what manner
the same is to be performed, as communicated to me by my foreign correspondents,
I claim,—
First. The use in combination with a single electrical circuit of two secondary
batteries, or two sets of such batteries, so connected with the circuit by means of
a commutator that while the one battery or set of batteries is or are being charged
with electricity from the circuit the other battery or set of batteries is or are
giving out its or their charge proviously received from the circuit, substantially as
herein described.
Second. Supplying to a dynamo-olectric machine a current proceeding from a
separate source of electricity and made to operate in combination with the current
produced in the dynamo-electric machine itself, substantially as and for the purposes
herein described.
Third. Supplying the electric current to electro-dynamic machines through a
centrifugal interrupter in such manner that when the speed exceeds a certain limit
the supply of the current is cut off and is not reestablished until the speed is again
reduced within such limit, substantially as herein described.
Fourth. The combination in one and the same circuit of an alternate current
dynamo-electric machine and one or more alternate current electro-dynamic
machines without commutators, so as to insure synchronous and constant motion
in all the machines irrespective of any resistancos, substantially as herein
described.
Fifth. The combination of two alternate current dynamo-electric machines driven
simultaneously at the same speed, the parts of the one machine being capable of having
their relative position shifted so as to differ from the position of the parts of the
other machine in order to vary the force of the combined current produced by the
two machines, substantially as herein described.
Sixth. The method of regulating the power of electro-dynamic machines on one
and the same circuit by placing in the circuit near the dynamo-electric machine
an indicator apparatus operating in combination with a centrifugal governor a
clutch apparatus and a rheostat situated in a secondary circuit whereby the
current of the latter is caused to modify the action of the generating machine
according as the speed of the electro-dynamic machines increases or decreases,
substantially as herein described with reference to Fig. 11 of the Drawings.
Seventh. Regulating the power of a dynamo-electric machine by the action of
an electro-dynamic machine placed in a derivation circuit, and operating in com-
bination with an indicator electro magnet and an armature having a brake in
such manner that the motion of the said electro-dynamic machine is stopped
when the current from the dynamo-electric machine is weakened, substantially
as and for the purpose herein described with reference to Fig. 12 of the Drawings.
Eighth. The method of conveying a quantity current to a distance with minimum
loss by first converting it into a high tension current by means of an induction
coil, which current after being conveyed to the distant station is there reconverted
into a quantity current by a second induction coil.
In witness whereof, I, the said John Imray, have hereunto set my hand and
seal, this Twenty-second day of March, in the year of our Lord One thousand
sicht hundoad and night, doven