Year: 1888

page_text: Date of Application, 1st Feb., 1888
Complete Specification Left, 24th Oct., 1888
Complete Specification Accepted, 14th Dec., 1888
1, LOUIS EDMOND SOLIGNAC, of 23 Boulevard de Strasbourg, Paris, France,
Engineer do hereby declare the nature of this invention to be as follows:-
This invention relates to the distribution of electricity by means of undulatory
currents having their points of inflexion rendered synchronous, so that they can act
upon a series of converters or secondary generators supplying a single system
of wire.
a
In every existing distributing system supplied with continuous or alternating
currents the difficulty of grouping the machines together necessitates in practice,
system of wire for each source of electricity, the synchronous motion of two
machines being impossible without attaching them to the same shaft; hence arises
the necessity for returning to the generator after the distribution of the energy
obtainable by the unit of source. This is the only serious objection to the electric
distribution by converters or secondary generators.
This inconvenience may be remedied by employing my system of distribution.
Suppose in order to fix the ideas I take any continuous current generator. The
current produced in this generator is divided into two branches which contain two
series of resistances.
Now, take a secondary generator having three wires. After having enclosed the
first series of resistances, the current is sent through the two branches the intensity
in the former branch will then be at the maximum, and almost nil in the second, if
the resistances are considerable. If now by means of a circular accumulator [
successively enclose the second series of resistances and at the same time open again
the first series, it is evident that the intensities will vary progressively in the two
branches and in inverso proportions.
The two wires act in the same direction to generate alternating currents in an
induced wire.
If now I arrange a series of secondary and primary generators under these con-
ditions, and actuate all our rotary commutators, after having connected them to one

page_text: shaft, by a single motor, I obtain perfect synchronism between the undulations of my
various secondary generators which I can then group for quantity or for tension in
order to supply alternating currents.through a single wire.
My system of wire is accordingly in principle, composed, of any continuous
sources which I send in two derivations varying in inverse ways in converters having
three wires placed at the central point of the continuous source and which themselves
give an alternating source which I pass into a single conduit, limiting myself when I
wish to augment the discharge from this system of wire to adding a new secondary
It will be understood that I reserve
generator, vibrating in unison with the others.
the right of modifying, according to the requirements of the applications, the
arrangements of details, for example of sending all my undulatory currents into a
single converter, or of modifying the system for actuating the resistances by
employing a commutator which is displaced by vibration, rotation or by alternating
motion, or the like.
Dotad this 1st dove of Fahrnarv 1888
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicant.

page_text: I, LOUIS EDMOND SOLIGNAC, of 23 Boulevard de Strasbourg, Paris, France,
Engineer, do hereby declare the nature of this invention and in what manner the same
is to be performed, to be particularly described and ascertained in and by the following
statement, and accompanying drawing, that is to say :-
There are many known methods of distributing electrical currents, but all of them
have inherent faults producing inconveniences which may be unimportant in the
laboratory but offer insurmountable obstacles in practice; as a brief examination
will show.
In distribution by means of a continuous current of low tension copper conducting
wires of such large section are required as to have led long ago to the abandonment
of this system for all important distributions.
With a current of high tension this difficulty disappears, but another and moro
serious one takes its place, that is to say the dangerous nature of the current supplied
to consumers, leading not only to accidents to the materials used but to persons, this
risk being so great that the employment of a current exceeding a maximum of
250 volts has long been abandoned.
Moreover both these systems have the disadvantage that they supply to all the
consumers a part of the principal current, so that in certain cases all the users are
sufferers by the imprudence or ill will of one.
The necessity for a modification of the system of distribution is therefore obvious
both in respect of the conversion of the primary current from one of high tension
and low quantity to one of low tension and high quantity for the use of the consumer,
and of the complete independence of all of the consumers among themselves.
With
this object two kinds of transformers are necessary, one for continuous and the other
for alternating currents.
The first system consists in the establishment of a series of electric motors in
connection with a general system of distribution, each of these motors constituting
practically a small local generating station from which the electricity produced by
generators actuated by the motors is distributed. In short, at a central station power
is converted into electricity of high tension distributed to the small local stations
where it is converted into work, which work again generates electricity of low tension
for distribution to the consumer. These successive conversions are the essence of
this system of distribution, which has not yet however been applied to industrial
purposes.
The system of transferring or converting an alternating current is however more
practicable, for it makes each consumer independent, as well as effecting the conversion
from tension to quantity, the only objection to its adoption being the use of the
alternating current which presents many difficulties.
In fact, there is little hope, notwithstanding the attempts and experience hitherto
made and acquired, of being able to group or work together, several sources of

page_text: electricity in an alternating form, for an absolute synchronism would be necessary in
the successive phases of the different machines, which synchronism it would be
impossible to obtain. Thus if a machine makes 2000 changes of current in a minute
whilst a neighbouring one only makes 1999, that is to say, that their speeds differed
only th part, the first will give out one current whilst the other will give out a
contrary current, and the two currents will neutralize each other.
It has however been found possible, though in a very uncertain and unsatisfactory
way, to couple together two alternating machines, but it is necessary that the driving
belts should be arranged so that they can slip upon their pullies when one machine
gains upon the other with which it is coupled, in-which case it tends to act as a motor
to the latter and to turn it in the contrary direction.
It is evident that this correction of speed cannot-be absolute, and that the curves of
the two machines will not coincide, all that can be obtained being a curve resulting
from the superposition of those resulting from the two coupled machines. Moreover
in practice this equilibrium between the two generators, being dependent upon one
revolution less, gives no security, and could not be applied to an installation having
a large number of generators or sources of supply.
Besides this difficulty in the central station the alternating current presents others
and serious ones with respect to the distribution. It is very difficult without occupying
much room to arrange side by side the wires which carry alternating currents vibrating
under the varying currents, for the induction from wire to wire would reduce the
available quantity to a serious extent over long distances.
To guard against this it is true that the distributing cable wire is made central,
whilst the return one is annular, but for high tension this is an arrangement which
presents grave danger, in view of the short circuiting which may so easily happen in
these conditions.
Moreover the use of alternating currents at the central station renders difficult the
supply of electricity for all its applications, for the transfer of power, and more
especially for electrochemical purposes. Finally it would be unwise in the present
state of electrical science to establish a system of electrical distribution necessitating
the use of a special form such as an alternating current only, to the exclusion of any
other form which may before long prove to be more advantageous, such for instance as
is afforded by the use of accumulators or the like.
It is therefore necessary, in order to meet all the requirements of a perfect
system of distribution, that the method employed should satisfy the following
conditions.
1. The possibility of distributing a current of high tension but low quantity on the
main line.
2. Of distributing current to the consumer, of low tension but of quantity propor-
tioned to his requirements.
3. Of rendering the consumers entirely independent of each other.
4. Of being able to arrange in the same conductor any number of wires which may
be rendered necessary by an unforeseen extension of the demand.
5. The establishment of an equilibrium between the production at the generating
station, and the consumption.
6. The possibility of giving a supply from several independent sources, in order
to facilitate the installation of plant and the increase and decrease of supply at the
different times arranged.
7. Of satisfying all the different applications of the electrical current which may
be required, with plant and material of a uniform type at the central generating
station.
8. A system of distribution such that it may be supplied from sources of any kind,
so as to keep up with the progress of electrical science.
9. That the system employed shall give the best possible result.
The system of distribution which forms the subject of the present invention perfectly
fulfills all these conditions.
For this
...
purpose.a a current transformer is used of any kind, but the inducer of

page_text: which is composed of several parts through each of which is passed a current of 0.5
of an ampére.
To facilitate the construction the inducer is formed as a woven material of which
the warp is formed of filaments or wires of 1 millemêtre and the weft of threads of
silk or cotton. In this way a ribbon 0.0012 thick and 5 centimètres wide can
contain 40 wires that is to say can pass 20 ampêres.
By means of a special commutator the current in each wire is reversed so that at
the first step or commutation there will be, in a transformer having 200 wires, 1 wire
with a current in one direction and 199 in the opposite direction, then 2 in one and
198 in the opposite direction, and so on until after half of the operation of the
commutator there will be 100 wires carrying a current in one direction and 100 in
the opposite direction, and at the end of its operation there will be 199 in the first
and 1 in the second direction.
The entire transformer will therefore by gradual steps have changed its polarity,
and the curves may be indicated as follows:-
:-
These undulating currents will generate alternating currents under the best possible
conditions, for instead of the characteristic curve of the current being a sinusoïd it
will be a perfect triangle.
The resistance of the machine will not vaiy, and sparking at the commutator
need not be feared, since its action takes place under a tension of 100 volts of an
ampêre, that is to say a very low quantity of energy.
If each current in the installation is rendered undulating by one of these
commutators, and if the whole of the commutators are actuated by the same driving
power and are all arranged in the same relative position, it is evident that all the
currents will undulate synchronously and that they will all simultaneously generate
alternating currents having a fixed and constant relation together, and that if the
transformers are then employed under those conditions the secondary currents will
have their poles relatively constant, that is to say that (for example) at any given
moment the currents entering all the wires of the secondary circuits will be positive,
and at the next negative, but all of them together, and that it will be therefore
possible to connect them together and consequently to supply a single distributing
wire.
The method of arrangement described, in which undulating instead of alternating
currents are used, enables all the above mentioned requirements to be satisfied.
1. It becomes possible to distribute a current of high tension but low quantity
through the principal wire or lead, since the secondary circuits need have only any
desired tension.
2. The consumer can be supplied with electricity of low tension but of the desired
quantity, since on the line the current is alternating and consequently all the advantages
of the ordinary transformer are available.
3. All the consumers can be rendered for the same reason entirely independent of
each other.
4. Any number of conducting wires can be arranged together parallel, since
their vibrations are synchronous and induction need not be dreaded. .

page_text: 5. An equilibrium is readily attained between the supply of electricity and the
consumption.
6. The several supply wires for the generators not being in metallic contact are
completely independent, and in an installation of ten generators (or dynamos) it would
only be necessary to have an eleventh as a reserve, whereas if in order produce the
required synchronism a single machine of ten times the power were used it would be
necessary to have another similar one of the same power as a reserve.
In the same way if a similar proportion were requisite for the other parts of the
installation it is evident that the capital would have to be doubled to provide the
necessary reserve, whilst by my improved system an additional tenth only would be
necessary. Further, the independence of the separate machines increases not only
their security, but allow them to be stopped and cut out one by one as the needs of
the consumers may require.
7. The improved system meets the application of electricity to all purposes, since
the central station produces a continuous current which can be distributed by special
wire for either motive power or for electro-chemical purposes, without in any way
modifying the plant at the generating station.
8. All forms of current can be equally well distributed by the improved system, for
the distributing conducting wires all operate with an alternating current, whilst that
of the supply is continuous, so that if in the future the accumulator should become a
practicable apparatus, or any new discovery should render possible the supply of
electricity from chemical sources, the improved system of distribution would be
admirably adapted for their use.
9. Finally with regard to results, the transformer with multiple wires realizes the
theoretical type of apparatus of the kind, for the characteristic curve of the primary
current is, in it, a series of triangles instead of sinusoid the part of which parallel to
the axes of the X is non-effective upon the inducer.
Moreover the series of operations, being capable of regulation at will by altering
the speed of the machine, all the inconveniences arising from the "Hysteresis" of the
iron are avoided, and the maximum of result is obtained.
In the accompanying drawing figure 1 is in illustration of my improved apparatus
for producing the undulating current. Figure 2 is a plan shewing the plate M
carrying the tubes with 87 contacts. d represents the entrance of the wires to the
inducer, and e their exit from it.
Figure 3 represents in plan the plate P having four sections. Each sector is in
contact with the ring.
The shaded part represents insulating material, the width of which is more than the
diameter of a tube in order to prevent short circuiting.
In figure 1, A is the contact tube consisting of an iron tube.a, mercury b, and a
copper stopper c which rubs upon the sector of the plate P. Nickel stems to the
contact pieces are shewn at B, and D are the heads of the contact pieces which come
in contact with the ends of the wires of the inducers. P. is a sector which receives
the current from one of the rings of the collector, P₁ the sector communicating with
the opposite one. R is an insulating plate, and S'a metal plate which carries it.
T is the axis of the apparatus, revolving between the screw t, and the bearing. v
-below.
E is the positive collector which brings the current to the two directly opposite
sectors P, Pi
1
The insulating disc H separates the negative collector K which brings the current
to the other two sectors which are diametrically opposite and at right angles to the
first two. I is the driving shaft which drives all the machines so as to assure their
synchronism and J represents a bevelled toothed wheel which makes 400 revolutions
whilst the pinion L makes 1000. The right hand side of figure 1 shews the apparatus
in elevation, and the left hand side in section.
Figure 4 is a diagram illustrating the entire system.
. A are generators supplying separate currents to the apparatus B₁ B₁ B₁ for
producing synchronous undulating currents, whence the currents pass to the trans-

page_text: formers D, D, D', the secondary currents from which are transmitted along the main
distributing wire, at any desired points in which local transformers Z, Z, Z, are
arranged, the secondary currents from which are supplied to consumers in the manner
and of the kind required.
All the sets of apparatus B1, B1, B¹, are driven at exactly the same speed by the
shaft I which is itself set in revolution by a suitable motive power at C¹.
Having now particularly described and ascertained the nature of my said Inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The novel system of electrical distribution, consisting in the use of electricity
supplied in continuous currents, but converted into undulating currents by a single
apparatus affecting the entire installation substantially in the manner and for the
purpose described and shewn.
Dated this 24th day of October 1888.
EDWARDS & Co.,
35, Southampton Buildings, London,
Agents for the Patentee.