THREE-PHASE VOLTAGE REGULATING DEVICE
FIELD OF THE INVENTION
This invention relates to a three-phase voltage regulating device. More particularly the present
invention relates to a new and improved servo motor operated three-phase constant voltage
stabilizer for uneven load and unbalanced voltage.
BACKGROUND OF THE INVENTION
Imbalance of phase voltages in three phase systems has long been a problem. The voltage
fluctuation is very harmful for end use equipments, which may get totally damaged or ma1
function. In production units or factories, whole production chain suffers and business losses are
compounded on multiple fronts. Wfih variation in voltage, energy loss also increases.
A switching regulator provides a regulated output voltage to a load from an unregulated
input voltage; these are intended to be efficient for converting a power source from one form to
another. A few common switching regulators used are Boost, where output voltage is greater
than input voltage and Buck where output voltage is less than input voltage, regulators.
Using the buck boost regulators several types of servo motor operated 3-phase constant
voltage stabilizer have been developed. These arrangements make use of buck boost with
dimmer, double-wound dimmerstat or are linear in construction to replace dimmerstat. Use of
buck boost and dimmerpr dimmer alone, increases the on load and load losses in the stabilizer
at continuous worst load conditions.
There are various existing devices in the market such as a device using dimmer and buck boost
assembly, wherein a carbon brush (es) moves on the periphery of dimmer. Input supply is given
to dimmer. Servo motor mechanism controls the movement of carbon bush over the dimmer
and based on the input voltage, current is fed to the primary winding of buck boost transformer
which increased decreases the output voltage to desired limit. Further.for 3-phase supply, three
such devices are used. This type of device uses more copper, core and other material. Its
efficiency is also low due to more no load and load losses.
Another kind of devices has double wound dimmer, a dimmer has double layer winding. On
outer winding, carbon brush moves in similar way as in device disclosed above. In this design
PATENTISELHI 29-07-20P6 17: 0 2
also losses are more and it has capacity limitation due to low heat dissipation of inner winding
layer.
One another device used is a linear type device, where 3 limb cores are used for 3-phase
supply. Each limb has two1 multi-layer windings which are attached with buck boast. Two sets of
carbon brushes are used for each winding. One carbon b~sihs u sed for low input voltage and
other is used for high input voltage. Such devices are suitable only for balanced voltage on all
phases. They use more material and have high no load losses.
These days emphasis is being given to high efficiency electrical equipment at an affordable
cost. Presently, the type of stabilizers available in the market, are either not very efficient or are
unable to properly handle unbalanced load conditions. They are bulky, use more material and
thus are costly to install and maintain.
To overcome the limitations associated with existing arts, there is a need to develop high
efficient equipment for maintaining constant voltage to save energy.
SUMMARY OF THE INVENTION
To overcome limitations in the prior art, and to overcome other limitations that will become
apparent upon reading and understanding the present specification, the present invention
discloses a system for a three-phase voltage regulating device.
In accordance with one embodiment of the invention, it provides a voltage regulating device that
includes a winding, at least one carbon brush providing a voltage input to the winding, a chainsprocket
arrangement and the carbon brush coupled to the chain-sprocket arrangement, a
servo motor that is used to control the carbon brush. The voltage regulating device is an auto
transformer, and is configured to work in an alternating current power system.
In one embodiment, a voltage regulating device has a winding comprising an inner and an outer
winding, the inner winding has a number of tums based on low input voltage and the outer
winding has a number of tums based on a difference of high input voltage and low input voltage.
In another embodiment, a voltage regulating device has a winding where cross section of an
inner winding is selected based on a net current at full load low voltage input current minus full
P A T E N T D E L H I 29-07-20?6 1 7 : 02
load output current and cross section of an outer winding is selected based on full load output
current.
In another embodiment, a voltage regulating device has a winding comprising a multi layer inner
winding and a single layer outer winding.
In yet another embodiment, a voltage regulating device has a winding comprising a single layer
inner winding and a single layer outer winding.
In one another embodiment, a voltage regulating device comprising, a contmller to control the
movement of the carbon brush as per inputl output voltage limits.
In one embodiment, a voltage regulating device comprising, a voltage output from a fixed
tapping on the winding, wherein the output tapping is taken from a tum of an outer winding
which corresponds to output voltage.
In another embodiment, a voltage regulating has output tapping points which are joined in
h
Q, parallel with a balance coil in between, wherein the balance coil takes care of any voltage
m m variation at output tapping points of windings two limb.
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-a .u-. In another embodiment, a voltage regulating device has a voltage input is given to the winding + V
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of each limb through at least one carbon brush which moves axially over the winding.
-.
S In another embodiment, a voltage regulating device is a three phase auto transformer, L
L
0 comprising of three single phase auto transformers for connecting phases.
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0
In one another embodiment, a voltage regulating device sends1 receives instructions to1 from an
7 online voltage monitoring tool.
- n -I In one another embodiment, a voltage regulating device is an auto transformer based voltage in regulating device and achieves higher efficiency to that of a buck boost based arrangement,
M
(V --
7
CO In one another embodiment, a voltage regulating device is an auto transformer based voltage
b
M regulating device and achieves higher efficiency to that of a dimmer based arrangement.
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0 v- PATENTDELHI 2 9 - 0 7 - 2 0 1 3 6 1 7 : 0 2
3 -
In another embodiment, a voltage regulating device has efficiency of the order of 97%-99%
In one embodiment, a voltage regulating device has a single layer or multi layered inner winding
and a single layer outer winding. These windings are connected in series. Innerwinding has
I
number of turns based on low input voltage. Outer winding has a number of turns based on a
difference of high input voltage and low input voltage.
In one another embodiment, a voltage regulating device has a winding where cross section of
inner layer (s) is selected based on a net current at full load low voltage input current minus full
load output current and cross section of outer layer is selected based on full load output current.
One another embodiment of the present invention provides a voltage regulating device that
includes a voltage stabilizer having at least three cores where each core is a two limb mitered
core, a two layer spiral winding on both legs of each core, the layers of the winding are
connected in series. The windings of both legs are connected in parallel and the voltage
regulating device is a three phase auto transformer.
In one another embodiment, a voltage regulating device has the mitered cores which are made
of CRGO material having low losses.
In one embodiment, a voltage regulating device has hndings which are connected to flow a flux
in the respective core in same (i.e. either clock-wise of anti-clock-wise) direction and flux density
in the respective core is proportionate to input voltage.
In another embodiment, a voltage regulating device comprising a voltage input applied from a
source for selectively stepping up or down output voltage to a load.
In another embodiment, a voltage regulating device comprising a voltage output taken from
tapping points which are joined in parallel with a balance coil in between, wherein the balance
coil takes care of any voltage variation at output tapping points.
In one another embodiment, a voltage regulating device has winding comprising a stepped core.
In yet another embodiment, a voltage regulating device comprising a controller, wherein the
controller regulates an output voitage.
P A T E W T D E L H I 29-07-20146 17: 02
These and various other advantages and features of novelty which characterize the invention
are pointed out with greater particularity in the claims annexed hereto and form a part hereof.
However, for a better understanding of the invention, its advantages, and the objects obtained
by its use, reference should be made to the drawings which form a further part hereof, and to
accompanying descriptive matter, in which there are illustrated and described specific examples
of a system and method in accordance with the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
A clear understanding of the key features of the invention summarized above may be had by
reference to the appended drawings, which illustrate the method and system of the invention,
although it will be understood that such drawings depict preferred embodiments of the invention
and, therefore, are not to be considered as limiting its scope with regard to other embodiments
which the invention is capable of contemplating. Accordingly:
FIG. 1 illustrates an exemplary voltage regulating unit system, according to one embodiment
of the invention.
FIG. 2 illustrates an exemplary voltage regulating unit system, according to another embodiment
of the invention.
FIG. 3 is a circuit diagram illustrating thecirwit constitution of the voltage switching regulator,
when supply is at low input volt, in an embodiment of the present invention;
FIG. 4 is a circuit diagram illustrating the circuit constitution of the voltage switching regulator,
when supply is at high input volt, in an embodiment of the present invention;
FIG. 5 illustrates an exemplary voltage regulating unit system, according to one another
embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
In the following, reference is made to embodiments of the invention. However, it should be
understood that the invention is not limited to specific described embodiments. Instead, any
combination of the following features and elements, whether related to different embodiments or
not, 'is contemplated to implement and practice the invention. Furthermore, in various
embodiments the invention provides numerous advantages over the state of the arts. However,
although embodiments of the invention may achieve advantages over other possible solutions
and1 or over the state of the art, whether or not a particular advantage is achieved by a given
embodiment is not limiting of the invention.
PATENTDELH.~ 29-07'-201'6 17: 02
Thus, the following aspects, features, embodiments and advantages are merely illustrative and
are not considered elements or limitations of the appended claims except where explicitly
recited in claims. Similarly, reference to the invention shall not be ~0nst~eads a
generalization of any inventive subject hatter disclosed herein and shall not be considered to be
an element or limitation of the appended claims except where explicitly recited in claims.
It is the principal object of the present invention to provide an improved auto transformer based
three phase voltage regulating device, which is designed for extreme voltage variations and
capable of managing unbalanced or uneven load and unbalanced voltage.
It is a further object of the invention to provide an improved three phase voitage regulating
device, which is a servo motor operated device and is buck boost free and capable of
maintaining constant voltage to save energy.
It is a still further object of the present invention to provide an improved three phase voltage
regulating device which is highly efficient and developed at affordable cost.
h
d) Embodiments of the present inyention provides a structure with less number of components, cn m fewer and less quantity of materials used in manufacturing of the regulator. Further, the
L assembly of the components is easier and relativety less skill dependent. It also takes less time -a .u- to manufacture. ' -+ -
N
E Various embodiments of the present invention eliminate the possibility of failure due to buck
L
0 boast or dimmer as earlier. The arrangement is completely free from Buck boost or dimmer
L
\ principles thus the losses observed are less, especially under no-load conditions high savings
V)
7. are observed.
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9
It is an object of the invention to provide a better efficiency to that of a buck boost based or
dimmer based regulatory arrangement. Further, the efficiency target is to provide an efficiency
7.
V) of the order 97% to 99% in comparison to other existing system where the efficiency is 95% to
M
N 97%.
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M It is also an object of the invention to provide better heat dissipation arrangement for saving the
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- device from excess heat based failures. 0.
-9 PATEIJTDELHI 2 9 - 0 7 - 2 0 8 6 1 7 : 0 2
3
It is an object of the invention to provide an arrangement where it is possible to regulate the
voltage from 200-520 volts to 40014151433 volt with a low impedance.
It is an object of the invention to provide a voltage regulating device has winding comprising a
stepped core in a radial cross section.
Embodiments of the invention provide high efficiency, low cost, low maintenance and less space
requirement. The devices are equally useful in hotels, hospitals, multi-storied buildings, mobile
towers, shopping malls, cinemas, factories where CNC machines are used, closely-knit colonies
and also in other big areas. This is possible due to low cost, high efficiency, easy customization
and fast assembly.
It is also an object of the invention to provide a structure with two layer windings which is put on
the multiple limbs for high voltage1 precision requirements and similar structure with windings on
one limb for smaller rating stabilizers in same fashion.
It is also an object of the invention to provide a structure with one winding on each limb for high
capacity requirements and similar structure with one winding on only one limb for smaller rating
stabilizen in same fashion.
The above and other objects of the present invention are achieved by employing an auto
transformer concept which eliminates the use of buck boost and dimmer, this in-tum reduces
the cost, size, and increases the efficiency.
Thus, embodiments of the invention may significantly reduce application development and.
overhead costs.
One of ordinary skill in the art will readily recognize, however, that embodiments of the invention
may be adapted for use with a wide variety of applications, .in different platforms, structures,
arrangements.
FIG. 1 illustrates an exemplary voltage regulating unit system 100 where an input voltage 102 is
supplied to a voltage regulating unit 104. The input voltage 102 can be uneven due to varying
loads, fluctuations, deterrent supply structure or other reasons. The voltage regulating unit 104
regulates the voltage using one. of the embodiments of the present invention and supplies an
output voltage 106.
A controller 108 controls the movement of the components within the voltage regulating unit 104
and helps in overall functioning of the voltage regulating unit 104. The controller 108 can be an
electronic controller which is a microprocessor based controller having instructions to perform
similar to various other types of voltage controllers. Intelligent monitoring and control of the
components of the voltage regulating unit 104 is performed using the contmller 108. The
contmller has a set of predefined instructions as embedded by the manufacturer or can have a
contmller interface 110 which interacts with a user to set the instructions for the 'voltage
regulating unit 104. The function of the controller 108 is thus to control the voltage in the volage
regulating unit 104.
In another embodiment for a three-phase voltage supply structure the voltage regulating unit
system 100 has three voltage regulating units 104a, 104b, 104c for the respective phases. The
respective input voltage 102 (a, b, or c) is supplied to a voltage regulating unit 104 (a, b, or c)
respectively. The input voltage 102 can be uneven due tovarying loads, fluctuations, deterrent
supply structure or other reasons. The respedive voltage regulating unit 104(a, b, or c)
regulates the voltage using one of the embodiments of the present invention and supplies an
output voltage 106. For each phase, a separate voltage stabilizer is made, so that voltage of
each phase is corrected individually. . .
A single controller 108 controls the movement of the components within the three phase
structure of the voltage regulating unit 104 (a, b, or c) and helps in overall functioning of the
voltage regulating unit 104 (a, b, or c). The controller 108 can be an electronic controller which
is a microprocessor based controller having instructions to perform similar to various other types
of voltage controllers. Intelligent .monitoring and control of the components of the voltage
regulating unit 104 (a, b, or c) is performed using the controller 108. The controller has a set of
predefined instruction set for the three phases as embedded by the manufacturer or can have a
controller interface 110 which interacts with a user to set the instructions for the three-phase
voltage regulating unit 104 (a, b, or c). The function of the controller 108 is thus to control the
voltage for all three phases of the voltage regulating unit 104 (a, b, or c)
PATENTDELHI 2 9 - 0 7 - 2 0 9 6 17: 02
FIG. 2 illustrates an exemplary voltage regulating unit system 200 where the input voltage 102
is supplied to the voltage regulating unit 104. The voltage regulating unit 104 regulates the
voltage using one of the embodiments of the present invention and supplies the output voltage
106.
The voltage regulating unit 104 has a servo motor 204, which controls the movement of a chainsprocket
arrangement 206. The movement of the chain-sprocket arrangement 206 moves a
carbon brush (es) 208. The input voltage 102 is fed in outer layer of the winding with two limbs,
of a core and windings component 202, through 'axially movable carbon brush (es) 208. The
carbon brush(es) 208 of both the limbs are connected in parallel. Two limit switches are
provided so that the carbon brush (es) 208 does not over shoot the desired limits. Control of
movement of the carbon brush (es) 208 is regulated by the controller 108. Two output points on
windings of both the limbs are joined in parallel with a balance coil 210 in between, the balance
coil 210 takes care of any voltage variation at output points of both limbs and provides the
output voltage 106.
In another embodiment for a three-phase voltage supply structure the voltage regulating unit
system 200 has three voltage regulating units lWa, 104b, 104c for the respective phases. The
respective input voltage 102 (a, b, or c) is supplied to a voltage regulating unit 104 (a, b, or c)
respectively.
For each phase, a separate voltage stabilizer is made, so that voltage of each phase is
corrected individually.
The voltage regulating unit 104 (a. b, or c) has a phase respective servo motor 204 (a, b, or c).
which controls the movement of respective chain-sprocket arrangement 206 (a, b, or c). The
movement of the chain-sprocket arrangement 206 (a, b, or c) moves a carbon brush (es) 208 (a,
b, or c). The input voltage 102 is fed in outer layer of the winding with two limbs (three such
pairs, each respective to one phase), of a respective core and windings component 202 (a, b, or
c), through axially movable carbon brush (es) 208(a, b, or c). The carbon brush(es) 208 (a, b, or
c) of both the limbs are connected in parallel. Two limit switches (to each phase) are provided
so that the carbon brush (es) 208 (a, b, or c) does not over shoot the desired limits. Control of
movement of the carbon brush (es) 208 (a,'b, or c) is regulated by a single controller 108. Two
output points (to each phase windings) of both the limbs are joined in parallel with a balance coil
P A T E N T Q E L H I 2 9 - 0 7 - 2 0 8 6 17: 0 2
210 (a, b, or c) to each phase in between, the balance coil 210 (a, b, or c) takes care of any
voltage variation at output points of both limbs (to each phase) and provides the output voltage
106.
FIG. 3 is a circuit diagram illustrating the circuit constitution of the voltage switching regulator,
when supply is at low input volt. The voltage regulating unit component 300 shows the internal
circuit diagram of the core and windings component such as of 202 (a, b, c) in one of the
embodiments.
Each of the voltage regulating unit 104 is a voltage stabilizer and has a two limb mitered cores
(one of 302a1, other of 302a2) made of CRGO electrical sheet steel. Flux density in the core is
chosen in such a way so that core does not get saturated even at highest input voltage. The two
limb cores will be separate for all three phases (totaling 3 pain of two cores in a 3-phase
structure).
A two layer winding (302al. 302a2) is put on the each limb. In case of smaller rating stabilizers
winding is put only on one limb. Decision to put winding on one' limb or on both limbs depends
upon the capacity of stabilizer and current rating of the carbon brush(es) 208. The number of
turns in each winding corresponds to higher input voltage requirement. Volt per turn is normally
taken as 1-1.2. Number of tums in inner layer corresponds to lower voltage requirement and
outer layer has number of tums corresponding to d~fference of higher input voltage and lower
input voltage.
Cross-section of inner layer is selected based on difference of high input current and output
current or low-input current and output current, whichever is more. Whereas, cross-section of
outer layer is based upon output current. Inner and outer layen are then connected in series.
Circuit diagram shows the flow of current and voltage where lo is Output current, liL is Input
current at low input voltage.
Two output points (to each phase windings) of both the limbs are joined in parallel with a
balance coil 310 (a, b, or c) to each phase in between, the balance coil 310 (a, b, or c) takes
care of any voltage variation at output points of both limbs (to each phase) and provides the
output current lo.
P A T E N T D E L H I 29-07-209'6 17: 02
In this case, windings are provided on both the limbs because maximum input current is more
than 60 Amp. Winding on one limb is made in clockwise direction while the winding of other limb
is made in anticlockwise direction.
For three-phase structure three such winding arrangements will be made respective to each of
the phase.
FIG. 4 is a circuit diagram illustrating the circuit constiiution of the voltage switching regulator,
when supply is at high input volt The voltage regulating unit component 400 shows the internal
circuit diagram of the core and windings component such as of 202 (a, b, c) in one of the
embodiments.
Circuit diagram shows the flow of current and voltage where lo is Output current, liH is Input
current at high input voltage.
Similar to earlier structure a two layer winding (402al. 402a2) is put on the each limb. Two
output points (to each phase windings) of both the limbs are joined in parallel with a balance coil
410 (a, b, or c) to each phase in between, the balance coil 410 (a, b, or c) takes care of any
voltage variation at output points of both limbs (to each phase) and provides the output current
lo.
For three-phase structure three such winding arrangements will be made respective to each of
the phase.
FIG. 5 illustrates an exemplary voltage regulating unit system 500, according to one another
embodiment of the invention. An online monitoring tool 502 communicates with the controller
108 to control the parameten for sending instructions for voltage regulation through the voltage
regulation unit 104 (a. b. c). The online monitoring tool 502 also receives inputs for the current
state of the voltage regulation unit 104 (a, b, c) through the controller 108. The controller 108
has the necessary components for the online receipt and sending of instructions. The
components include a wired or wireless internet connection, relay, sensor units, and other
agents for communicating with the sohare installed for the online monitoring tool 502. Data
storage 504 keeps a check and record of all the functions and data collected or send time to
time.
PATENTDELHI 29-07-20i16 1 7 : 02
It is an object of the present invention to reduce the operation & maintenance cost of installed
equipment. For this task on-line voltage condition monitoring equipments provide focused.
purposeful diagnosis information, so that remedial measures can be initiated for insipient faults..
Equipments work with a standard communication protocol and are linked to server which has
powerful analysis sohare to estimate the extent of deterioration and effect of failure on real
time basis and thereby forecast any defect or ageing.
Among various parameters some of the recorded parameters are winding temperature, output
voltage and controller performance, continuous log of voltage & current on all three phases,
peak demand conditions, etc. With the help of these tools we can prepare the graphical
representations which will be useful for data analysis and will help in planning preventive.
maintenance schedules, life estimation and replacementl repair plan, asset life extension by
providing analysis & control, maintaining reliability, energy, saving and load management,
minimization of the long-term operational cost, cost saving by eliminating the unplanned
maintenance, and in time procurement of spare parts to get competitive rates, etc.
One of the embodiments have been shown with readings of Single phase. 20 KVA, input
voltage 175 to 280 V, and output voltage of 230 V.
Calculations:
Volt/ turn (taken as)
Tums corresponding to low input
Tums corresponding to high input
Tums corresponding to output voltage
Tums in inner layer
Tums in outer layer
Output tapping from top of outer layer
Current at low input
Current at High input
Output current
Winding provided on single1 both limbs
Cross-section of inner layer corresponds to
Cross-section of outer layer corresponds to
1.1
159
255
209
159
(255-159) = 96
255-209= 46 tums
114.3 Amp
71.43 Amp
86.96 Amp
Both (connected in parallel)
Higher of {(I1 4.3-86.96)12=13,67) &
((86.96-71.43)12=7.77) i.e. 13.67 Amp
86.9612 = 43.48 Amp
P A T E N T D E L H I 29-07-20% 17: 02
In one of the embodiments of the current invention, the data was recorded for the various
combinations and following readings were observed.
~ossibleK VA rating, input voltage range and output voltage are as follows:
The following tables show that no-load losses are less and efficiency is more in case of
, proposed invention as compare to normal voltage stabilizer with buck boost and dimmer.
P A T E N T D E L H I 29-07-20136 17: 02
Output Voltage
400 to 433
400 to 433 .
400 to 433
400 to 433
400 to 433
KVA
15-200
15-225
15-240
15-260
15-300
Input Voltage Range
242-520
260-520
280-520
300-520
340-500
Table 1.1 shows the input voltage supplied, output voltage obtained at various KVA readings
under No Load Losses, Load Losses. Total Losses conditions and efficiency obtained with
dimmer type switching regulator i.e. using dimmer witching regulator arrangement under the
already available structures in arts.
Auto Transformer Type
7
0
9
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W Table 1.2 shows the input voltage supplied, output voltage obtained at various KVA readings
0 under No Load Losses, Load Losses. Total ~ossesco nditions and efficiency obtained with auto
7
V) transformer type switching regulator i.e. using one of the embodiments of the present invention.
M cu 7
CO The t'able 1.2 further shows that the auto transformer based voltage regulating device achieves
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M . higher efliciency.to that of a dimmer based arrangement.
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9 P A T E N T O E L H I 2 9 - D7-20i46 1 7 : 02
The table 1.2 further also shows that the autotransformer based voltage regulating device has
efficiency of the order of 97%-99%.
In accordance with a preferred embodiment of this invention, there is provided a voltage
regulating device comprising; a winding, a voltage input to' the winding, wherein the voltage
input is provided by a carbon bmsh to.the winding and wherein the carbon brush is coupled to a
chain-sprocket arrangement and controlled using a servo motor.
In accordance with another preferred embodiment of this invention, there is provided a voltage
regulating device comprising; a winding, wherein said winding has an inner winding and an
outer winding and wherein the inner winding has a number of turns based on low input voltage
and the outer winding has a number of tums based on a difference of high input voltage and low
input voltage, and wherein cross section of the inner winding is selected based on a net
current at full load low voltage input current minus full load output current and cross section of
the outer winding is selected based on full load output current and wherein the inner winding
can be single layer or multi-layer and the outer winding can be single layer.
In accordance with one other prefemd embodiment of the present invention, there is provided a
voltage regulating device, wherein said voltage regulating device is a three phase auto
transformer, preferably works in an alternating current power system.
In accordance with one other preferred embodiment of the present invention, there is provided a
voltage regulating device, wherein said voltage regulating device is a three phase auto
transformer, preferably works as a stabilizer, wherein the stabilizer is having three two limb
mitered cores.of CRGO material. On both legs of each core spiral windings are laid which are
connected in series. Windings of both legs are connected in parallel. These windings are made
and connected in such a way, so that flux in the core flows in the same direction (i.e. either
clockwise or anti clockwise) properly. This type of arrangement eliminates use of auxiliary
winding which may otherwise be required for reducing impedance voltage.
In accordance with one other preferred embodiment of the present invention, there is provided a
voltage regulating device, wherein the winding has a stepped core in radial cross-section and
the core is having two legs and wherein on both legs of a core, a two layer spiral windings are
laid which are connected in series, windings of both legs are connected in parallel and wherein
the voltage input is applied from a source for selectively stepping up1 down output to a load.
In accordance with one other preferred embodiment of the present invention, there is provided a
voltage regulating device, wherein the winding has a stepped core and the core is having two
legs and wherein on both legs of a core, a spiral windings, the layers of which, are connected in
series, windings of both legs are connected in parallel and wherein the volage input is applied
from a source for selectively stepping up1 down output to a load.
In accordance with another embodiment of the present invention, there is provided a voltage
regulating device, wherein the carbon brush is also moved manually and wherein the two limit
switches are provided so that the carbon brush does not over shoot the desired limits.
In accordance with one other preferred embodiment of the present invention, there is provided a
voltage regulating device, wherein said voltage regulating device further provides an output from
a fixed tapping on the winding and wherein the output tapping is taken from the turn of outer
winding which corresponds to output voltage. Input is given to this winding through carbon
brush(es) which moves axially over the winding. Movement of carbon brush is through chain
and sprocket arrangement and is controlled with the help of servo motor mechanism. Two limit
switches are provided so that the carbon brush does not over shoot the desired limits.
According to the present invention, the voltage regulating device is developed based on the
concept of auto transformer, thereby quantity of major material such as copper, core, oil, steel
etc as well as losses are reduced. This in-tum reduces the cost, size, and increases the
efficiency. Stepped core in radial cross-section reduces conductor length and copper losses.
While the present invention has been described in terms' of particular embodiments and
applications, in both summarized and detailed forms, it is not intended that these descriptions in
any way limit its scope to any such embodiments and applications, and it will be understood that
many substitutions, changes and variations in the described embodiments, applications and
details of the method and system illustrated herein and of their operation can be made by those
skilled in the art without departing from the spirit of this invention.

We Claim:
1. A voltage regulating device, comprising:
a winding;
at least one carbon brush, wherein a voltage input to the winding is provided by
the carbon brush;
a chain-sprocket arrangement, wherein the carbon brush is coupled to the chainsprocket
arrangement;
a servo motor, wherein the servo motor is used to control the carbon brush;
wherein the voltage regulating device is an auto transformer, and is configured to
work in an alternating current power system.
2. The voltage regulating device as 'claimed in clai,m 1, wherein the winding further
comprises an inner winding and an outer winding, the inner winding has a number of
tums based on low input voltage and the outer winding has a number of tums based on
a difference of high input voltage and low input voltage.
3. The voltage regulating device as claimed in claim 1, wherein cross section of an inner
winding is selected based on a net current at full load low voltage input current minus full
load output current and cross section of an outer winding is selected based on full load
output current.
4. The voltage regulating device as claimed in claim 1, wherein the winding further
comprising a multi layer inner winding and a single layer outer winding.
5. The voltage regulating device as claimed in claim 1, wherein the winding further
comprising a single layer inner winding and a single layer outer winding.
6. The voltage regulating device as claimed in claim 1 further comprising, a controller to
wntrdl the movement of the carbon brush as per input/ output voltage limits.
7. The voltage regulating device as claimed in claim 1 further comprising, a voltage output
from a fixed tapping on the winding, wherein the output tapping is taken from a tum of an
outer winding which corresponds to outpj voltage.
8. The voltage regulating device as claimed in claim 8, wherein the output tapping points
are joined in parallel with a balance coil in between, wherein the balance coil takes care
of any voltage variation at output tapping points.
9. The voltage regulating device as claimed in claim 1, wherein the voltage input is given to
the winding through at least one carbon brush which moves axially over the winding.
10. The voltage regulating device as claimed in claim 1, wherein the voltage regulating
device is a three phase auto transformer.
1
11. The voltage regulating device as claimed in claim 1,. wherein the voltage regulating
device sendl receive instruction to1 from an online voltage monitoring tool.
12. The voltage regulating device' as claimed in claim 1, wherein the voltage regulating
device has efticiency of the order of 97%-99%.
13. A voltage regulating device, comprising:
a voltage stabilizer, wherein the stabilizer is having:
at least three cores, wherein each core is a two limb mitered core;
spiral windings on both legs of each core, wherein the layers of the
winding are connected in series;
wherein the windings of both legs are connected in parallel;
wherein the voltage regulating device is a three phase auto transformer.
14. The voltage regulating device as claimed in claim 13, wherein the windings are
connected to flow a flux in the respective core in same direction and flux density in the
respective core is proportionate to input voltage.
15. The voltage regulating device as claimed in claim 13, further comprising a voltage input
applied from a source for selectively stepping up or down output voltage to a load.
P A T E N T D E L H I 2 9 - 0 7 - 2 0 1 % 1 7 : 02
.16. The voltage regulating device as claimed in claim 13, further comprising a voltage output
taken from tapping points which are joined in parallel with a balance coil in between.
wherein the balance coil takes care of any voltage variation at output tapping points.
17. The voltage regulating device as claimed in claim 13, wherein the winding further
, .
comprising a stepped core.' . .. .. . ..
18. The voltage regulating device as claimed in claim 13, further comprising a controller, '
wherein the controller regulates an output voltage.
19. The voltage regulating device as claimed in claim 13, wherein the voltage regulating
device send1 receive instruction to1 from an online voltage monitoring tool.
20. The voltage regulating device as claimed in claim 14, wherein the voltage regulating
device has efficiency of the order of 97%-99%.