Improvements in Apparatus for Transforming Alternating into Continuous Electrical Currents and conversely.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Transforming Alternating into
Continuous Electrical Currents and conversely.
I, CHARLES DENTON ABEL, of Birkbeck Bank Chambers, Southampton Buildings,
Chancery Lane, in the County of London, Consulting Engineer and Chartered Patent
Agent, do hereby declare the nature of this invention (as communicated to me from
abroad by La Société Anonyme pour la Transmission de la Force par l'electricité, of
13, Rue Lafayette, Paris, France, Manufacturers,) to be as follows:-
Polyphase alternating electric currents have been transformed into continuous
currents by means such as are indicated in Fig. 1 of the accompanying drawings
applied to biphase currents.
Around two magnetic cores A B and A¹ B₁ are wound 1st two equal primary
coils P and P¹, the one in the circuit of the currents of the one phase, the other in that
of the other phase, and 2nd a number 2n of secondary windings each consisting of
two coils one on each of the cores A B and A¹ B¹. The number of windings of these
coils follows the law given in the following table in which is a constant
indicating a certain number of windings. The numbers in terms of Sines represent
windings in the one direction and those in terms of Cosines represent windings in
the opposite direction.

page_text: as shewn in Fig. 1.
numbered
p and
+
When two brushes F1 F2 bear simultaneously on the segment
the circuit which connects these brushes in passing round the
cores A B and A¹ B include a number N¹ of windings around A B and a number N
around A¹ B₁ such that-

page_text: This solution is according to the present invention extended to the case where
there is only one source of primary alternating currents. This has already been done
by first decomposing the primary current into two with phases displaced, by means
of arrangements comprising condensers. It has been found by experience that when
capacity is given to a network it is impossible to avoid resonant effects producing
dangerous elevations of voltage, the following arrangement is therefore substituted
for that previously employed.
The
Retaining the cores A B and A' B₁ and their windings, while A B is covered by a
primary current P' directly connected to the network, the circuit P¹ is suppressed and
for its action is substituted that of an inductor I excited by a continuous current
and moveable around an axis G in the direction A¹ B¹ as shewn in Fig. 2.
primary circuit around A¹ B¹ had to produce a double effect, 1° to develop at every
moment a number of ampère turns equal but of opposite sign to the number of
ampère turns developed by the secondary circuits, and 20 to develop at every
moment a number of ampère turns capable of generating the necessary inducing
flux in the core A¹ B¹. The variations of these two numbers of ampere turns would
be displaced relatively by period.
In order that the rotation of the inductor I may fulfil the office of the primary
circuit, it should present to the core A B successively the coils, the one J having a
number of ampère turns equal at every moment to the maximum number of those
developed by the secondary circuits round A¹ B, the other coil; having a number
of ampère turns proportional to the maximum intensity of the flux developed in
the cores. The cores J and j should therefore be connected at 90° to one another, J
being in series with the external circuit connecting the brushes F1 F2 (Fig. 1) and
the intensity of the current traversing it being always proportional to the expenditure
of the apparatus. On the other hand the coil ; is connected in shunt between
the brushes. Under those conditions this transformer will operate in exactly the
same manner as the transformer of biphase currents. But in order to maintain the
rotation of the inductor I, it should always be supplied with a quantity of work
equal to the energy which its rotation supplies to the secondary circuits.
This is effected as shewn in Fig. 3.
The inductor I instead of reacting only on the secondary circuits A' B', is caused
at the same time to react on a primary circuit p p which is branched directly on the
network, and has its magnetic axis ac y at right angles to A¹ B¹. Then the inductor
as it passes before the circuit p p takes from it a certain quantity of work which it
restores period after to the secondary circuits of the core A¹ BI.
The inductor I and the circuits which act on it constitute not only a special trans-
former, but also a synchronous motor operating the current transformer properly so
called.
Figs. 4 and 5 shew such a motor having 6 poles. Its stationary part consists of a
crown A B of plates cut as shewn at a bc. Around the cores B are arranged
coils N1 N2No each having one sinusoidal winding, which are connected in parallel
or in series, reproducing the sinusoidal winding on the core A¹ B₁ of Fig. 1. The
variations of flux of which these various circuits are the seat are all of the same
phase and consequently, if this phase is suitable, they are the seat of the same
electromotive forces as if they had covered the core A¹ B₁ and had formed part of
the transformer of biphase currents. These circuits are connected with each other
and with those which surround the magnetic core A B exactly as shewn in Fig. 1
and as if for transforming biphase currents. All round the crown A B next
the air space are notches like those in the inductors of asynchronous machines,
these notches receiving windings as in asynchronous machines for alternating
currents, forming 6 bobbins n¹ n²
so that the poles developed by this
Nº.
It may
circuit are between those of the poles developed by the bobbins N¹ N°
This circuit is in fact the primary circuit p p of the arrangement in Fig. 3.
be branched directly on the main leads or closed on a special secondary circuit
arranged around the core A B. Within A B is another crown CD rotating around

page_text: the axis O and perforated all round its circumference to receive-1º bolts such as a
as near as possible to the air space all connected together by copper rings on each
side of C D, so as to form a magnetic screen enveloping the inductor and ensuring
synchronous movement; 2° two crossed windings the one R shewn in full lines, the
other S in dotted lines. These two windings are like those of the inductor of an
asynchronous motor for biphase currents, but the one is of coarse wire in series with
the external circuit through which the machine causes a continuous current to pass,
the other of fine wire in shunt between the brushes of the collector. For passage of
these currents there are three rings V1 V2 V3 on the axis 0, one of them serving for
return, on which bear three stationary independent rubbers. On the same axis
fixed the collector E E having brushes f to collect the continuous current. This
collector has three times as many segments (as there are 6 poles) as there are separate
sections of the secondary circuit of the transformer, which in the drawings are by
way of example taken to be 12. The collector segments are connected every twelfth
together, so as to form 12 distinct groups each comprising 3 segments connected in
parallel.
is
On the axis O there are also 12 rings d each connected to one of the 12 groups of
the collector segment. On these rings bear rubbers which connect to the 12 sections
of the secondary circuit of the transformer. The collector might be fixed, the brushes
turning round it.
Dated this 20th dow of AL
mber 1000
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Transforming Alternating into
Continuous Electrical Currents and conversely.
I, CHARLES DENTON ABEL, of Birkbeck Bank Chambers, Southampton Build-
ings, Chancery Lane, in the County of London, Consulting Engineer and Chartered
Patent Agent, do hereby declare the nature of this invention (as communicated
to me from abroad by La Société Anonyme pour la Transmission de la Force par
J'electricité, of 13, Rue Lafayette, Paris, France, Manufacturers,) and in what manner
the same is to be performed to be particularly described and ascertained in and by
the following statement :-
The drawings hereinafter referred to are those accompanying the Provisional
Specification.
Polyphase alternating electric currents have been transformed into continuous
currents by means such as are indicated in Fig. 1 of the accompanying drawings
applied to biphase currents.
Around two magnetic cores A B and A¹ B₁ are wound 1st two equal primary coils P
and P¹, the one in the circuit of the currents of the one phase, the other in that of
the other phase, and 2nd a number 2 of secondary windings each consisting of two
coils one on each of the cores A B and A¹ B. The number of windings of these coils
follows the law given in the following table in which O is a constant indicating a
eertain number of windings. The numbers in terms of Sines represent windings in

page_text: These 2 circuits are connected with one another and with the segments of a
collector as shewn in Fig. 1. When two brushes F1 F2 bear simultaneously on the
segment numbered P and pn, the circuit which connects these brushes in passing
round the cores A B and A¹ BI include a number N¹ of windings around A B and a
number N2 around A¹ B' such that

page_text: If the cores A B and A¹ B₁ are the seat of variation of flux such that every winding
round A B is the seat of an electromotive force = 1° Cos. 2 a t, and every winding
round A B¹ is the seat of an electromotive force h² 1° Sin. 2 at, then the total
electromotive force between the brushes.is
-
This solution is according to the present invention extended to the case where there
is only one source of primary alternating currents.
This has already been done by first decomposing the primary current into two with
phases displaced, by means of arrangements comprising condensers.
It has been found by experience that when capacity is given to a network it is
impossible to avoid resonant effects producing dangerous elevations of voltage, the
following arrangement is therefore substituted for that previously employed.
Retaining the cores A B and A¹ B' and their windings, while A B is covered by a
primary current P directly connected to the network, the circuit P¹ is suppressed and
for its action is substituted that of an inductor I excited by a continuous current and
moveable around an axis G in the direction A¹ B¹ as shewn in Fig. 2. The primary
circuit around A' B₁ had to produce a double effect, 1° to develop at every inoment
a number of ampère turns equal but of opposite sign to the number of ampère
turns developed by the secondary circuits, and 20 to develop at every moment a
number of ampère turns capable of generating the necessary inducing flux in the
core A¹ B¹. The variations of these two numbers of ampère turns would be displaced
relatively by period.
In order that the rotation of the inductor may fulfil the office of the primary
circuit, it should present to the core A. B successively the coils, the one J having a
number of ampère turns equal at every moment to the maximum number of those
developed by the secondary circuits round A¹ B¹ the other coilj having a number of
ampère turns proportional to the maximum intensity of the flux developed in the
cores. The cores J and j should therefore be connected at 90° to one another, J
being in series with the external circuit connecting the brushes F1 F2 (Fig. 1) and
the intensity of the current transversing it being always proportional to the
expenditure of the apparatus. On the other hand the coil is connected in shunt
between the brushes. Under those conditions this transformer will operate in exactly
the same manner as the transformer of biphase currents.
But in order to maintain the rotation of the inductor I, it should always be supplied
with a quantity of work equal to the energy which its rotation supplies to the
secondary circuits. This is effected as shewn in Figure 3.
The inductor I instead of reacting only on the secondary circuits A¹ B¹, is caused
at the same time to react on a primary circuit pp which is branched directly on the

page_text: network, and has its magnetic axis y at right angles to A¹ B. Then the inductor
as it passes before the circuit pp takes from it a certain quantity of work which it
restores period after to the secondary circuits of the core A¹ B₁. The inductor I
and the circuits which act on it constitute not only a special transformer, but also a
synchronous motor operating the current transformer properly so called. Figs. 4
and 5 shew such a motor having 6 poles. Its stationary part consists of a crown A B
of plates cut as shewn at a bc. Around the cores B are arranged coils N¹ N² - N°
each having one sinsusoidal winding, which are connected in parallel or in series,
reproducing the sinusoidal winding on the core A¹ B₁ of Fig. 1. The variations of.
flux of which these various circuits are the seat are all of the same phase and
consequently, if this phase is suitable, they are the seat of the same electromotive
forces as if they had covered the core A¹ B₁ and had formed part of the transformer
of biphase currents. These circuits are connected with each other and with those
which surround the magnetic core A B exactly as shewn in Fig. 1 and as if for
transforming biphase currents.
All round the crown A B next the air space are notches like those in the inductors
of asynchronous machines, these notches receiving windings as in asynchrous
machines for alternating currents, forming 6 bobbins n¹ n².
so that the poles
developed by this circuit are between those of the poles developed by the
bobbins N1 N2
No. This circuit is in fact the primary circuit p p of the
arrangement in Fig. 3. It may be branched directly on the main leads or closed on
Within A B is another
a special secondary circuit arranged around the core A B.
crown CD rotating around the axis 0 and perforated all round its circumference to
receive 10 bolts such as e as near as possible to the air space all connected together
by copper rings on each side of CD, so as to form a magnetic screen enveloping the
inductor and ensuring synchronous movement; 2° two crossed windings the one R
shewn in full lines, the other S in dotted lines. These two windings are like those of
the inductor of an asynchronous motor for biphase currents, but the one is of coarse
wire in series with the external circuit through which the machine causes a continuous
current to pass, the other of fine wire in shunt between the brushes of the collector.
For passage of these currents there are three rings V1 V2 V3 on the axis 0, one of them
serving for return, on which bear three stationary independent rubbers. On the same
axis is fixed the collector EE having brushes f to collect the continuous current.
This collector has three times as many segments (as there are 6 poles) as there are
separate sections of the secondary circuit of the transformer, which in the drawings
are by way of example taken to be twelve. The collector segments are connected every
twelfth together, so as to form 12 distinct groups each comprising 3 segments
connected in parallel.
On the axis O there are also 12 rings & each connected to one of the 12 groups
of the collector segment. On these rings bear rubbers which connect to the 12
sections of the secondary circuit of the transformer. The collector might be fixed,
the brushes turning round it.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
A transformer having two distinct magnetic cores provided with secondary windings
the number of convolutions of which around each core vary according to a sinusoidal
law in passing from one convolution to the other on the same core, and from the one
core to the other in the same winding, these several windings being connected
together and with the successive segments of a collector like the sections of the
armature of a continuous current machine. The necessary variations of flux are
determined in the first core by the presence of a primary circuit by the alternating
currents which are to be utilised and in the second core by the rotation of an inductor
excited by two circuits of a continuous current arranged so as to develop inter-
crossing cores; the one of these circuits is connected in shunt between the brushes

page_text: of the collector, the other is connected in series with the external circuit in which
the current obtained is utilised. This apparatus is reversible and can serve to
transform a continuous current of constant voltage into a simple alternating current
of constant effective voltage.