Improvements relating to the Transformation and Distribution of Energy by Alternate Electric Currents.
Year: 1890

page_text: Date of Application, 9th Apr., 1890-Accepted, 10th May, 1890
COMPLETE SPECIFICATION.
Improvements relating to the Transformation and Distribution of
Energy by Alternate Electric Currents.
I, JONAS WENSTRÖM, of Orelro, in the Kingdom of Sweden, 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:-
This invention relates to a triple conductor system in which alternating currents
of three different but evenly spaced phases are generated by special machinery
transmitted and distributed in separate conductors and converted and utilized either
separately by the usual converters, lamps, motors and other apparatus or in
combination with each other by special converters, motors and apparatus.
Accordingly my invention comprises not only certain arrangements of the
conductors, their branches and connections but also the special features of the
generators, converters and motors necessarily used in combination therewith..
The principal object of this invention is to provide means for exciting revolving
magnetic fields but other results besides this are obtained wiz. :-The maximum
difference of potential between the mains is reduced and the size of conductors.
decreased with the same power distributed and the output of the generator is
increased.
•
In the accompanying drawing the invention and the principal features thereof are
shown diagrammatically as their application is not limited to any special forms but
may be introduced in combination with several types of apparatus.
In the said drawing
Figures 1 and 2 indicate the arrangement of the coils and connections in the triple
alternating generator.
Figure 3 indicates the arrangement of the coils and connections in the triple
motors and
Figure 4 shows the same in the triple converter.
Figure 5 shows the system of conductors and apparatus for distribution in
series and
Figures 6-11 the systems of the same parts arranged for distribution in
parallel.
In generators for alternating currents the armature usually carries one series or
set of coils of such a number and location in relation to the magnetic field, that
the induction varies similarly in all coils viz.:-all coils are always in the same
phase of induction. But to avoid inefficient windings in these coils they must limit
their occupation of the armature to only part of the space available for them on it.
On the contrary in the alternating current generators or triple alternator used in
my invention these vacant spaces are filled by two extra sets of coils, required for
producing the three currents of different phase above referred to as an esential feature
of my invention.
Accordingly I provide the armature with three separate sets of coils evenly, and
regularly distributed round it as not to leave any vacant space on the armature,
while at the same time each coil occupies the most efficient situation for the induc-
tion. Thus the capacity of the machine is increased without increasing the size or
speed of it.
The several coils of each set are connected together as usual to cooperate either
n series or in parallel or in multiple series according to circumstances, Figure 1
ndicating part of the armature winding and corresponding magnet poles, shows how
the three different series of coils 1, 2 and 3 may be distributed on the armature in
elation to each other, and to the magnet poles S N. Thus it will be seen that the coils

page_text: are equally pitched and regularly distributed, and (by overlapping each other) that
they fill up all gaps round the armature. It will also be seen that the three series
of coils will pass the fields in succession with a difference in phase of a third of a
period of alternation accordingly generating the three currents of equal pitch but
different phase here required.
Figure 2 indicates how the three sets of coils are connected up. with each other
and with the three terminals of the machine in order to attain this object. Each
set is represented by only one coil and the several fields are also represented by
one field viz. two poles S N. As the sets 1, 2 and 3 are evenly distributed round
the axle of the machine, the induction in each set obviously must
vary with
alternations, which differ in phase by a third period from those of the other sets. If
the sets are supposed to be wound in the same manner regularly round the armature,
thus similar ends of their conductors ;-viz. :-either interior or exterior, either first or
last ends will be connected together as indicated at o which point. I will call the neutral
point, and which connection may be used as a fourth terminal (referred to hereafter)
but which usually is left alone inside the armature. The other three ends a, b and c
are each connected to separate terminals from which the three currents referred to
are supplied to the three mains.
Instead of combining these three sets of coils in one arniature, three separate
armatures in different machines or in the same magnet frame may be used for the
generation of the currents here required. In these cases the armatures or their
shafts are rigidly keyed together with due lag to insure that the induction in the
armatures always differ in phase from each other with a third period. The terminals
of the different machines are connected together as above stated so that similar
ends are connected to a neutal point .and the other three left as terminals in the
triple system.
Obviously the mains receiving currents from such alternators must act as return
conductors to each other, a fact which results in saving of material, and the difference
of potential must turn out lower when such currents of different phase are used as in
this case.
The same triple alternators may be used as motors if coupled to mains supplying
currents of the properties here named. But such currents are adapted particularly
for special triple motors without commutators or sliding contacts, as these three
alternate currents of equal pitch but different phases easily lend themselves for
excitation of revolving fields. In Figure 3 such a motor is represented diagram-
atically. As in the triple alternator, Figure 2 the coils 1, 2 and 3 may each be
substituted for a series of several coils connected in series or parallel according to
circumstances though here for simplicity only one coil of each set is indicated and
sometimes this may agree with the real case. Here also the coils are supposed to be
wound regularly in the same order and then the similarly situated ends a, b, c will
each be connected to one of the three mains while the remaining ends o will be
connected together as a neutral point. But in certain cases hereinafter referred to
these ends also will be separately connected with special terminals.
The cords may also be placed on other suitable parts of the magnetical structure
and this may be arranged otherwise than here shown as explained with regard to the
converter.
By virtue of this arrangement the differently phased currents excite fields of
varying and different power and direction by each coil or set of coils. But as the
alternations are of equal pitch and as they lag in phase is a third of a period the
combined effect of all coils evidently results in the creation of a revolving field
through part of the magnetic conduits of the motor. This revolving field reacting on
the structure in which it is created, compels that part to revolve which is conveniently
arranged to be movable. This movable part being an armature d as indicated or that
part in which the coils are deposited, depending on the circumstances.
As triple converters three separated simple converters of any usual type acting
together one for each current may be used. These converters may also be bodily
combined in one structure in order to save space and material. But to be used with

page_text: this triple system of distribution the type of triple converter indicated in Figure 4 is
particularly adapted. The three currents in the three primary coils or sets of coils m
unite in their action on the secondary coils or sets of coils n both primary and
secondary coils being wound on the same system of magnetic cores. Accordingly
similar ends of the primary coils are connected to the primary mains while the three
other ends are united in a neutral point. But to suit certain cases hereafter referred
to these ends may also be separately connected with three separate terminals.
Similar ends of the secondary coils also are united in a neutral point, and the three
others connected to the secondary mains. But in certain cases these neutral points
may also here be divided. Thus the three primary currents are transformed by the
triple converter in three secondary currents of equal pitch and difference in phase
which characterized the primary currents but altered in tension and quantity to suit
the purpose desired.
Either or both of the primary and secondary sets of coils may be placed on other
parts of the magnetic structure than those shown in Figure 4; for instance as shown
at p. The triple converter may also have a magnetic structure of other arrangement
than that shown in figure 4. Thus the exterior and interior parts may be arranged
laterally and the radial parts connecting them in a direction parallel to the axis. The
same is the case with the triple motor.
The part of the core of the triple converter, in which the field is excited in
combination by all primary coils, this part may be surrounded by one or more coils
giving secondary simple alternating currents. Thus is given a converter for trans-
forming triple currents into simple currents.
The triple currents may also be transformed into direct currents through an
apparatus the triple commutator-being a triple motor in combination with a
rectifying commutator.
In this case a triple motor is made to rotate a commutating apparatus with such a
speed that it will synchronize with the pitch of the alternating currents. The
alternate currents are applied to the commutator through sliding contacts on rings
connected to the separate segments of the commutator. Thus each receive impulses
of the same direction, when in the same position, which impulses are conducted from
the apparatus by other sliding contacts, rubbing on the commutator seginents.
This triple commutator thus consists of a synchronized triple motor, on the shaft
of which are fixed three insulated rings and one insulated commutator, composed of
three separate crowns or series of combined segments. The segments of each crown
are evenly distributed round the commutator and are placed between those of the
other in such a way that the brushes rubbing over them will pass in succession one
segment of each crown. The three insulated rings are each connected with its crown
of segments, which thus each receive impulses from its separate current through the
rubbing contacts on the rings. Upon the commutator rub one or several pair of
brushes which collect the direct currents and conduct them to the terminals. To
bring about this the motor must be designed to drive the commutator at such a speed,
that a certain brush will touch the segments of a certain crown once in a period of
alternation.
Having thus described the apparatus necessary for generating, converting and
utilizing the special currents used in my invention it remains to specify the system of
distributing circuits and its connection with the said apparatus.
The system of distribution may be in series or in parallel or both combined.
Starting from the triple alternator the three currents are transmitted through
three separate mains or sets of mains and may directly be utilized in lamps motors
or other apparatus, or else previously converted one or more times by suitable
converters.
In Figure 5, explaining the series distribution, G represents the triple alternator,
from the terminals of which the three conductors a, b and c are running through the
lamps or other simple current apparatus L, L. These three mains are connected at
their further ends ŕ thus completing the series system,

page_text: K indicates how a triple converter may be inserted-to transform the currents to a
higher or lower pressure, M. represents a triple motor fed by the three mains. In
this case the neutral point referred to above is divided in three more terminals to
allow the insertion of the notor in series as required. N shows how a triple con-
verter is used to throw out branch circuits and similarly a mixed triple and simple
converter as described above may be inserted to transform from the triple system to
the simple system.
In these converters the neutral point in the primaries also are changed to three
terminals in order to continue the mains beyond them.
The connecting point or the separate ends of the conductors there united may be
connected back to the neutral point of the alternator or to that of the converter
from which the currents concerned are supplied.
In the system of parallel distribution, the currents may also be used directly from
the generator or may be transformed once or several times by suitable converters
before reaching the lamps or other apparatus, where they are to be utilized.
In order to show more plainly the two different modes for parallel distribution,
Figures 6-11 represent cross sections of the three conductors a b and c issuing from
the alternator or converter concerned.
As will be seen by Figures 6 and 7 the mains may each be connected through
lamps L or other simple current. apparatus either separately to both (Figure 6) or to
a common neutral point connection (Figure 7). These points may then be
located on a fourth conductor or "neutral or equalizing main," which also may be
connected to the neutral points in the alternators, motors or converters, in which
the currents concerned are generated or utilized.
As usual the connecting links between the mains may have branches directly or by
simple current converters and these branches may be utilized separate or in combi-
nation as do the mains or connectors named.
Figures 8 and 9 show how the two modes of cross connections will combine their
action in the case of triple motors, and Figures 10 and 11 indicate the same on behalf
of triple converters.
In the case of Figure 8 the motor M must have its neutral point divided, thus
carrying the six terminals here necessary for the connections. But in the plan
Figure 9 the neutral point remains closed with or without connection with the
neutral main referred to. Similarly in Figure 10 the converter K must get its
primary wires connected to six terminals, ris. the neutral point will be parted, but
in Figure 11 this point must remain closed. As to the secondaries not shown in the
drawings for simplicity they may in both cases be united or separated at their neutral
point, depending on how they are connected to the secondary mains; whether with
six terminals as the primary in Figure 10 or with but three, as the primary in
Figure 11.
As before stated secondaries may also be arranged to produce one or more
alternating simple currents instead of these triple currents. Then the secondaries
evidently will have two terminals connected to two mains. Finally triple commuta-
tion may be inverted both in the series and in the parallel system to transform the
triple currents into direct currents.
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:-
First. Triple alternators supplying three separate alternate currents of equal pitch
but differing in phase from each other by a third of a period of alternation; these
alternators being for this purpose provided with armatures carrying three coils or
sets of coils evenly distributed round the armature; or provided with three armatures
in one magnet frame; or consisting of three separate alternators with their shafts
connected, each set of coils in every case in such a position to the other that they
lag from each other with a third of the pitch between the magnet poles.

page_text: Second. The similarly deposited ends of the said coils or sets of coils being con-
nected, each to its terminals and the remaining three ends united to a neutral point
which may be connected to a fourth terminal.
Third. The said currents being used in special motors to produce revolving fields,
which are excited by three separate coils or sets of coils on any convenient parts of
suitable magnetic frames and each traversed by one of the currents.
Fourth. The said coils or sets of coils having each of three similarly situated ends
connected with its terminal and the other three ends either united to form a neutral
point which may be connected with a fourth terminal or separated and each connected
to its terminal.
Fifth. Any convenient part of said motor being arranged movable and made to
rotate.
Sixth. The said three currents separately connected in three separate or in one
structure combined converters, or converted in combination by special triple con-
verters, to supply currents of changed tension and quantity, but of said triple
properties.
Seventh. The converters containing three primary coils or sets of coils, each
traversed by one of the primary currents, which coils are placed on convenient parts
of the magnetic structures and connected to each other and to the mains to suit the
circumstances as stated in regard to the triple motor.
Eighth. The converters containing three secondary coils or sets of coils, placed
on suitable parts of the structure and conveniently connected to each other and to
the terminals, as said in connection with the motors.
Ninth. The converter containing three primary coils or sets of coils but only one
secondary coil or set of coils placed on the part of the magnetic structure in which
the induction of the primaries act in combination, thus producing secondary currents
of usual simple alternating kind.
Tenth. The triple currents transformed into direct currents by commutating
apparatuses driven synchronously by said triple motors that the segments of one of
the three separate crowns of the commutator may pass a certain brush in the same
pitch as that of the alternating currents.
Eleventh. The said triple currents of said properties and distributed in series or
provided by triple conductors, each conductor acting as return to the others.
Twelfth. The said system when arranged in parallel, carrying connectors through
the apparatuses either bridging directly and separately cross over between the mains
or branches, or running from each main or branch to a common neutral point or
neutral main or equalizing conductor, which also may connect other neutral points
of the same order.
Dated this Oth day of Anril 1890
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.