Improvements in the Distribution of Electricity through Accumulator Batteries.
Year: 1890

page_text: Date of Application, 2nd Dec., 1890
Complete Specification Left, 1st Sept., 1891-Accepted. 17th Oct., 1891
PROVISIONAL SPECIFICATION.
[Communicated from abroad by Messrs. SIEMENS & HALSKE, of Berlin, in the
German Empire, Electrical Engineers.]
Improvements in the Distribution of Electricity through
Accumulator Batteries.
We, SIEMENS BROTHERS & Co. LIMITED of 12 Queen Anne's Gate,
Westminster in the County of Middlesex, Electrical Engineers, do hereby declare
the nature of this invention to be as follows:-
According to this invention, electrical generators and accumulator batteries are
arranged in combination with a system of distribution in the manner represented
diagrammatically by the accompanying drawing. The electric generator M is
made in a number of parts, each a separate dynamo machine or set of machines, of
which three m', m², m³ are shewn in the drawing, but there may be a greater
number.
The accumulator battery A is made in a corresponding number of parts a¹ a² a³.
The leads to and from the terminals of the dynamo machines are so arranged and
provided with switches S that the machines can be connected wholly or partly
parallel or in series to the leads L by which the batteries are charged.
One part a¹ of the battery A is always in direct connection with the distribution
leads B; the other parts a² a³ of the battery have the leads to and from them
provided with switches T, so that they can be connected wholly or partly
parallel or in series to the distribution leads.
By varying the switch connections, the supply to the distribution leads in respect
of tension and quantity may be suited to the greater or less demand at different
times and at different hours of the day.
Instead of one distributing network as shewn there may be several of these fed
from the dynamos and batteries, and these networks may be arranged on the three
wire system.
Dated this 2nd day of December 1890.
ABEL & IMRAY,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in the Distribution of Electricity through
Accumulator Batteries.
We, SIEMENS BROTHERS & CO. LIMITED, of 12 Queen Anne's Gate, Westminster
in the County of Middlesex, Electrical Engineers, 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 :-
The object of the present invention is to effect the charging of an accumulator
with a higher potential difference than its discharge, and consists in an arrange-
ment, which not only suits this purpose but also permits of charging and discharging
being carried on simultaneously.
This object has already been attained by arrangements previously proposed, but
with such arrangements there must be just as many separate distributing networks
as there are accumulator-batteries in series, and there are considerable objections
to the use of this arrangement when the several distributing networks are differently,
loaded:

page_text: According to the present invention this defect is obviated, so that it is possible
to make use of one distributing network.
We will proceed to describe the said invention with reference to the accompanying
drawing which shows diagrammatically an example of a plan of connections for
this purpose.
A is an accumulator-battery, which in this case for example is able
to produce on discharge a potential difference which is three times the normal
potential difference of the distributing network. The battery A is for this purpose
divided into three equal parts a¹, a, a, which may consist either of three sets of
cells, each arranged in series, or of three sets in series, the cells of each set being in
compound parallel, and one of these parts-for example a¹-is connected to the
distributing retwork either directly or through a cell-regulating switch. The
remaining parts of the battery a², a³, are arranged and provided with switches in
such a manner that they can be readily joined up in parallel or in series with the
part a', either by hand or by devices actuated from a distance.
The plant M for generating the electrical energy can also be separated into a
number of parts m² m² m³ equal to those of the accumulator, and also so arranged
that the separate parts m² m² m³ can be joined in series or in parallel
simultaneously with those of the accumulator. In many instances it will suffice,
if the accumulator has to be divided into n parts to divide the generating plant
into two parts only, one of which is capable of producing a potential difference
equal to the charging potential difference of - th of the charging potential
difference of the whole battery, while the other produces a potential difference
which is n-1th of the charging potential difference of the whole battery. It is
of course necessary that the potential difference of the generating plant should so
far exceed the potential difference of the battery as to make up for the loss of
potential in the leads.
n
72
The above described arrangement acts as follows:-
During those hours of the day, when the demand on the distributing network is
small, the parts a¹ a² a³ of the battery are joined up in series, and similarly the
parts m² m² m³ of the generating plant, and the battery is charged at a potential
difference which is three times that of the distributing network (always taking into
account the difference between charging and discharging current, and the loss in
the charging leads).
Then the part a¹ of the battery supplies steadily so much current to the
distributing network as to satisfy the small demand, and this part of the total
current produced is drawn from the charging current of the part a', so that the
parts a² as become more fully charged than the part a'. Accordingly the relative
capacity of the parts a¹ and a² a³. a may be different. As the day advances,
the demand for current increases; whereupon all the parts of the accumulator as
well as of the generating plant are simultaneously joined up in parallel, and the
discharge of the battery begins, and can be carried on with three times the current
which was used for charging. The generating plant can now also give current
direct to the distributing network.
n-l
This can be done, either by the parts m² m² m³ of the generating plant being, like
the accumulators, joined up in parallel, or that part of the generating plant, which,
as above explained, gives the potential difference is switched off, and the
part of the generating plant left at work is confined to that which gives the potential
difference
n
•
n
,
If, during the discharge of the battery, a greater part of the total current
than 1th is to be furnished by the generating plant direct to the distributing.
network, then, during this comparatively short time, the feeding mains L L, which
n

page_text: connect the generating plant with the accumulators can be strained higher than
during the charge; whilst the potential difference of the current giving dynamo is
increased either by increasing its speed, or its magnetic field, or in any other way.
It is of course not necessary with the present arrangement of distribution, that all
the parts al a² a³. . . of the accumulator and m² m² m³ . . . of the generating
plant should always be joined up either in parallel or in series.
On the contrary
the parallel or series connection can be made step by step in accordance with the
increasing or decreasing consumption of current in the network.
"
So long as the batteries are being charged, the part a¹ which is permanently
connected up to the network, will receive less current than the other parts a² a³
since a portion of that current which traverses the latter, serves to supply the lamps.
When the discharge begins, and the part a² is put in parallel with the part a', the
part a will not receive so much current as the parts a³ a
If it be assumed that the putting in parallel takes place by n successive
steps, then each part "a" of the battery will receive fewer "ampère-hours," than
the part denoted by the letter "a" with the next higher index, (a* -³, a" - 2 &c.).
If more than two parts a of the battery are to be connected at the same time in
parallel and in series, then the above considerations naturally apply to these
groups only. The same consideration applies also to the discharge, for as soon as
the succeeding part is connected in parallel to the preceding part, the discharge of
both will automatically divide itself proportionally to the charge.
The division of the generating plant must always depend on the division of the
accumulator, so that for each step in the parallel connection of the accumulator a
connection of the dynamos can be made, which will produce a potential difference
corresponding to the potential difference required by the arrangement of the
accumulator.
It will be obvious that nothing will be altered in the present method of
distribution, if the network be laid on the three wire system.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In the distribution of electrical energy, the provision, between the consuming
apparatus and the generating plant, of an accumulator battery which is divided into
an optional number of equal parts a¹ a² a³
a", of which each part is so
arranged that its discharge potential difference is equal to the potential difference
required by the consuming apparatus plus the loss of potential difference occurring
in the leads, only the one part a' being in permanent connection with the distributing
network, while the other parts are either wholly or partially so arranged relatively
to the said one part that they can be charged with a potential difference equal to
the sum of the potential differences of all the parts a connected in series, while
at the same time the discharge of the said one part a¹ takes place at the potential
difference required by the consuming apparatus, substantially as described.
I
2. The method of discharging the electrical energy from the arrangement of
accumulator batteries referred to in the preceding claim in such manner, that the
separate parts a¹ a² a³
a of the battery A are partially or
wholly connected with each other in parallel while the corresponding
parts m' m² m²
m" of the generating plant M are connected together
either in parallel or in such manner that their total potential difference corresponds
to the potential difference for the time being of the accumulator batteries, the loss
of potential difference in the charging main L being taken as greater than during
the charging, substantially as described.
Dated this 1st day of Santambor 1901
ABEL & IMRAY,
Agents for the Applicants.