Improvements in Electricity Distribution.
Year: 1892

page_text: Date of Application, 21st May, 1892
Complete Specification Left, 18th Feb., 1893-Accepted, 22nd Apr., 1893
PROVISIONAL SPECIFICATION.
Improvements in Electricity Distribution.
We, WILLIAM BURGESS EDGAR, Electrician, 10 Strone Terrace Partick,
North Britain, and JOHN MACINTOSH MACKAY MUNRO, of The Munro's
Electrical Manufacturing Company Limited, 9 Holland Place Glasgow do hereby
declare the nature of this invention to be as follows:- .
The object of this invention is to improve compound wound dynamos so that they
may be more conveniently used for the distribution of electricity.
1st. Where several dynamos are run in parallel feeding a constant potential ring
main through one or more pairs of feeders the feeders being common to all the
dynamos or each dynamo supplying a separate pair of feeders.
2nd. Where the number or resistance of feed mains may be added to or
diminished.
3rd. Where additional dynamos may be added to run in parallel with dynamos
first installed or arranged for.
In this inventien a pilot wire or supplementary conductor (or a pair of such
wires, the system being applicable to either positive or negative wires or both)
connecting a feeding point, or other analogous point of an electricity distribution
system, with a point at or near to the feeding dynamo, is utilized so as to act as the
compounding or over compounding portion of the dynamo coils.
Suppose for example that an ordinary compound wound dynamo is connected
through long feeder mains to a feeding point from whence the distribution branches
radiate. If the ordinary compounding just keeps the pressure curve level at the
dynamo terminals then the pressure at the distributing point will of course fall as
the current increases. This is usually remedied by slightly over-compounding the
dynamo. If however for any reason the line resistances are increased or diminished
or the maximum current to be sent through it is increased, dynamos being
supplemented by other dynamos, it is a costly and troublesome operation to
rewind or alter the dynamo to suit, and bridging coils are wasteful and do not
automatically adjust themselves to changes. To avoid the need of this we carry
a portion of the conducting wire direct from the dynamo terminal or preferably
from the junction of its compounding with its over compounding coils to the
feeding point or other analogous point. Adding this wire or increasing or reducing
its section has we find no very appreciable effect in disorganizing the dynamo
winding so designed to secure a constant potential at the feeding point. Or to
state it somewhat differently. Let there be a dynamo supplying current to a
feeding point, and let this dynamo be preferably compounded in the ordinary
manner to maintain a constant electro-motive-force at its own terminals, the
dynamo being then connected to a pair of feeders. If now a wire be taken say
from its positive terminal-outside of its compound coil and carried round the
magnets and thence as a supplementary. wire to the feeding point direct or to
an intermediate point of proportionate resistance then if the uumber of the
turns round the magnet are properly suited to its duty the machine will be over-
compounded for constant potential at the feeding point but will differ from ordinary
over compounding in this chiefly that the ordinary feeder mains may be added to
or diminished, or the number of dynamos added to without materially distorting
the constant potential curve at the feeding point.
These special compounding or over compounding coils may be passed in series

page_text: round several dynamos, or one dynamo may be so treated by a common coil, the
other dynamo being left free to regulate themselves by it.
Dated this 20th day of May 1892.
BOTTOMLEY & LIDDLE,
154, St. Vincent Street, Glasgow, Applicants' Agents.
COMPLETE SPECIFICATION.
Improvements in Electricity Distribution.
We, WILLIAM BURGESS EDGAR, Electrician, 10 Strone Terrace, Partick,
North Britain, and JOHN MACINTOSH MACKAY MUNRO of The Munro's Electrical
Manufacturing Company Limited, 9 Holland Place, Glasgow, 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 this invention is to improve compound wound dynamos so that they
may be more conveniently used for the distribution of electricity.
1st. Where several dynamos are run in parallel feeding a constant potential ring
main or net-work through one or more pairs of feeders, the feeders being common
to all the dynamos, or each dynamo supplying a separate pair of feeders.
2nd. Where the number or resistance of feeder mains may be added to or
diminished. .
3rd. Where additional dynamos may be added to run in parallel with dynamos
first installed or arranged for.
In this invention a pilot wire or supplementary conductor (or a pair of such
wires, the system being applicable to either positive or negative wires or both)
connecting a feeding point or other analogous point of an electricity distribution
system with a point at or near to the feeding dynamo, is utilized so as to act as the
compounding or over compounding portion of the dynamo coils.
Suppose for example that an ordinary compound wound dynamo is connected
through long feeder mains to a feeding point from whence the distribution branches
radiate. If the ordinary compounding just keeps the pressure curve level at the
dynamo terminals, then the pressure at the distributing point will of course fall as
the current increases. This is usually remedied by slightly over-compounding the
dynamo. If however for any reason the line resistances are increased or diminished,
or the maximum current to be sent through it is increased, dynamos being supple-
mented by other dynamos, it is a costly and troublesome operation to rewind or
alter the dynamo to suit, and bridging coils are wasteful, and do not automatically
adjust themselves to changes. To avoid the need of this we carry a portion of the
compounding wire preferably from the junction of its compounding with its over-
compounding coils, to the feeding point or other analogous point. Adding this wire
or increasing or reducing its section has, we find, no very appreciable effect in
disorganising the dynamo winding so designed to secure a constant potential at the
feeding point. Or to state it somewhat differently. Let there be a dynamo
supplying current to a feeding point, and let this dynamo be preferably com-
pounded in the ordinary manner to maintain a constant electro-motive force at its
own terminals, the dynamo being then connected to a pair of feeders. If now a
wire be taken say from its positive terminal-outside of its compound coil and
carried round the magnets, and thence as a supplementary wire to the feeding point
direct to an intermediate point of proportional resistance then if the number of
the turns round the magnet are properly suited to its duty the machine will be over
compounded for practically constant potential at the feeding point, but will differ
from ordinary over compounding in this chiefly that the ordinary feeder mains may
be added to or diminished, or the number of dynamos added to without materially
distorting the constant potential curve at the feeding point.
One or both supplementary conductors-when it is applied to both positive and

page_text: negative feeders-may be passed in series round several dynamos, or one or more
such specially compound dynamos may be supplemented by ordinary shunt or even
compounded dynamos driven by separate engines run with open stop valves and
coupled to the same omnibus bars or feeders. These dynamos so long as they are
not too large proportionately to the regulating machine would regulate themselves
to suit the load.
In cases where the potential between the terminals of the brushes at no load and
full load varied much it would be advisable to connect the shunt coil to a source of
constant potential.
In order that our invention may be properly understood and readily carried into
effect we have hereunto appended a diagrammatic view showing our arrangement as
applied to both wires from dynamo, of which A is the armature, B, B₁ the brushes,
and b b the terminals of the brushes. C is the shunt coil, while D D' are the
series coils, and F F the over-compounding coils. E E¹ are the feeders, and
G G¹ the pilot wires or supplementary conductors. H H are the feeder points on
ring main or net-work. ZZ are the terminals proper of the dynamo as an ordinary
compound dynamo which may be either on the dynamo or switchboard.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:
1. A system of electric distribution combined with the special over compounding
coils and supplementary conductors applied to either one or both feeders substan-
tially as described.
2. A system of electrical distribution wherein the dynamos are over compounded
by a current caused to flow in the over compounding coils by virtue of the difference
of potential between two points on a feeder, substantially as described.
Dated this 17th day of February 1893.
BOTTOMLEY & LIDDLE,
154, St. Vincent Street, Glasgow, Applicants' Agents.