Improved Method of and Apparatus for Regulating the Electro-motivé Force of Electric Generators.
Year: 1893

page_text: Date of Application, 9th June, 1893
Complete Specification Left, 9th Mar., 1894-Accepted, 14th Apr., 1894
PROVISIONAL SPECIFICATION.
Improved Method of and Apparatus for Regulating the Electro-motivé
Force of Electric Generators.
I, JOHN SMITH RAWORTH, of 112 Belvedere Road, Lambeth in the County
of Surrey, Engineer, do hereby declare the nature of this invention to be as
follows:-
:-
The object of my invention is to provide apparatus of simple construction and
efficient in action for regulating the electro-motive force produced by one or more
electric generators. At present the usual practice is to regulate, by means of
rheostats, the field currents of dynamos or their exciters, but this method has the
disadvantages of entailing considerable complication in the connections. Further-
more the current to be dealt with is often considerable, and there is always the
danger of the circuit becoming accidentally broken at some point between the
dynamos and the regulating device.
According to my invention I regulate the electro-motive force of an electric
generator or generators by acting upon the governor of the engine driving the said
dynamo or its exciter, or of each such engine, when more than one are used by
means of an electro-magnet or solenoid of sufficient strength to control the speed
of the engine to the required extent. When several dynamos or exciters with
their engines are worked in parallel, the controlling electro-magnets or solenoids
are or may be placed in one circuit either in series or in parallel, and the current
in the said circuit may be governed either by a suitable rheostat worked by hand
or by an automatic device, or by varying the electro-motive force in the circuit, as
for instance by varying the number of cells in a primary or secondary battery
connected with such circuit.
The advantages of my arrangement which is especially suitable for central
stations, are, that the current to be dealt with is very small and the controlling
circuit is not an essential part of the system of generation, consequently the
breaking of the circuit would not cause a cessation of current in the dynamos.
The arrangement is extremely simple and enables the regulating room to be placed
at any convenient distance from the dynamos to be regulated.
Dated this 9th day of June 1893.
W. LLOYD WISE,
Per. F. J. Brougham.
COMPLETE SPECIFICATION.
Improved Method of and Apparatus for Regulating the Electro-motive
Force of Electric Generators.
1, JOHN SMITH RAWORTH, of 112 Belvedere Road, Lambeth, in the County
of Surrey, 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 :-
The object of my invention is to provide apparatus of simple construction and
efficient in action for regulating the electro-motive force produced by one or
more electric generators. At present the usual practice is to regulate, by means
of rheostats, the field currents of dynamos or their exciters, but this method has

page_text: the disadvantages of entailing considerable complication in the connections.
Furthermore the current to be dealt with is often considerable, and there is
always the danger of the circuit becoming accidentally broken at some point
between the dynamos and the regulating device.
According to my invention I regulate the electro-motive force of an electric
generator or generators by acting upon the governor of the engine driving the
said dynamo or its exciter, or of each such engine when more than one are used,
by means of an electro-magnet or solenoid of sufficient strength to control the
speed of the engine to the required extent. When several dynamos or exciters
with their engines are worked in parallel, the controlling electro-magnets or
solenoids are or may be placed in one circuit, either in series, or in parallel, and
the current in the said circuit may be governed either by a suitable rheostat
worked by hand or worked by an automatic device, or by varying the electro-
motive force in the circuit, as for instance by varying the number of cells, in a
primary or secondary battery connected with such circuit.
The advantages of my arrangement, which is especially suitable for central
stations, are, that the current to be dealt with is very small and the controlling
circuit is not an essential part of the system of generation, consequently the
breaking of such circuit would not cause a cessation of current in the dynamos.
The arrangement is extremely simple and enables the regulating room to be
placed at any convenient distance from the dynamos to be regulated.
In the accompanying drawings,
Figs. 1 & 2 are elevations at right angles to each other, and Fig. 3 a plan, of
an engine governor combined with a regulating solenoid according to this
invention.
Fig. 4 is a diagrammatic view showing the general arrangement of circuit,
solenoids, governors and rheostat for governing the speed of several engines
driving a corresponding number of exciters or dynamos.
Referring to Figs. 1, 2 and 3, a is a solenoid fixed to a support in proximity to
the engine governor c and having its movable cores d connected by a rod e and
link e with one arm of a lever the other arm f¹ of which serves to resist more
or less the rise of the governor balls, and in this way regulate the action of the
governor so as to cause the engine to which the governor is fitted to run at
different speeds according to the position, for the time being, of the solenoid cores,
and so regulating the electro-motive force of the electric generator driven by the
said engine.
The solenoid is placed in an electric circuit in which is inclosed a rheostat by
which the action of the solenoid can be varied to control the action of the engine
governor and consequently the electro-motive force of the electric generator driven
thereby, to suit requirement.
In the arrangement shown diagrammatically in Fig. 4 there are three engines g
the controlling solenoids a of which in this case are shown as adapted to be placed
in parallel across the regulating circuit wires h¹ which are connected with any
suitable source of electric energy-it may be from the mains, or from a separate
battery or dynamo and the difference of potential between which can be
regulated at will by a rheostat k in circuit with one of these wires.
With this arrangement it will be obvious that the several solenoids will pull
simultaneously and can be varied together, so that one regulating device serves to
control the speed of all the engines and the dynamos connected therewith.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. Regulating the electro-motive force of an electric generator by means of an
electro magnetic device adapted to act upon the governor of the engine driving the
said electric generator or its exciter and included in a circuit the current in which
is regulated by a rheostat substantially as herein described.

page_text: 2. For regulating the electro-motive force of an electric generator or electric
generators, the combination with the governor of the engine used for driving the
said electric generator or its exciter, or with the governor of each engine when
several are used for driving separate electric generators of an electro-magnet or
solenoid arranged in an electric circuit provided with a rheostat for controlling the
current passing therethrough, substantially as described.
Dated this 9th day of March 1894.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.