FORM 2
THE PATENT ACT 1970
(39 of 1970)
&
The Patents Rules  2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)

TITLE OF THE INVENTION: “An Energy Conservation System with a Planned Load Shedding Transformer”
1. APPLICANT:

1. (A)NAME : Uttar Gujarat Vij Company Ltd.(UGVCL)
(B)NATIONALITY : Indian
(C)ADDRESS : Regd & Corporate Office
Visnagar Road 
Mehsana - 384001
Gujarat  India.

2. (A)NAME : Vidhia Electrotrans Industries
(B)NATIONALITY : Indian
(C)ADDRESS : 309  GIDC Engineering Estate
Sector: 28  Gandhinagar - 382028
Gujarat  India.

2. PREMABLE TO THE DESCRIPTION
PROVISIONAL
The following specification describes the invention. þ COMPLETE
The following specification particularly describes the invention and the manner in which it is to be performed.

Field of the invention
The Present invention relates to an energy conservation system with a transformer for catering single phase power supply. More particularly  relates to a system with a planned load shedding transformer for providing continuous / uninterrupted power supply for restricted enhancement. This system is exclusively applicable in power sector and especially where the motive power load shedding is practically difficult due to misuse of the energy by means of unauthorized usage of phase converters.

Back ground and prior art of the invention
Initially  when ample power supply was available  all rural feeders were given 24 hours 3 phase power supply (till late ""80s). With the increasing agricultural demand and rapid load growth  it was increasingly difficult to meet the demand due to paucity of generation capacity. Load-shedding and load-roistering was introduced itself. The number of no-power supply hours increased to 8 to 12 hours and rural feeders were necessarily required to be switched off during morning and evening peak hours.

In order to meet the requirements of rural populations for power supply during evening peaks  a two-phase power supply system instead of three-phase power supply was introduced. However  in this system  only one phase was getting full voltages and remaining two phases were getting dim voltages on LT side. It was  therefore  decided that the line side phase  which has been disconnected  may be looped with connected phase on load side  so that full voltages are available at least in two phase in the LT network so as to minimize the low voltage problems for residential connections in the villages. The load roistering system was modified to 8 to 14 hours of 3-phase power supply and 10 to 12 hours of single phase power supply and 3 to 4 hours of ""No-power"" supply as per the availability of generation.

This system worked satisfactorily for some time; however  with the passage of time  the agriculture consumers started using power supply for irrigation purpose with the use of phase converters. The usage of phase converters became so rampant that the load during single phase power supply was even more than three phase power supply  as the agricultural connections are scattered over a large area  it was difficult to stop them using phase converters. The agricultural consumers started pumping out water more and more  increasing the area of irrigation and depleting the ground water levels. This has tremendously increased the energy requirement on rural feeders; pumps of higher and higher capacity were deployed by agricultural consumer""s unauthorised. This has deteriorated the power supply system resulting into the failure of distribution transformers  generation of negative sequence components  low voltages and poor quality of power supply. Any measures for energy conservation or water conservation were futile  as the agricultural tariff was on flat horsepower base. There was no incentive to agricultural consumers for saving energy or water.

The conventional systems mentioned above  did not serve the purpose as the systems could not control the misuse of energy by phase converter or deprived of the power supply during the load shedding period to the villages / hamlets / farm houses. And hence  it was necessary to introduce full proof system  which can restrict the misuse of energy by phase converters as well as cater the energy requirement to lighting consumers of villages / hamlets / farm houses.

In west part of India  all the villages have started getting uninterrupted 3-phase power supply  with the segregation of the Agriculture load from the rural load (Villages). The level of satisfaction of rural consumers due to 24 hours power supply has gone up and a qualitative change in the standard of living has taken place due to increased job opportunities  working hours and recreational facilities. The aspirations of the rural population  is still living in small scattered hamlets and in the filed. So far  they were getting 8 hours three phase power supply and 10 to 14 hours single phase power supply  but with declaring the existing rural feeders as pre-dominantly agricultural feeders and restricting three phase power supply on these feeders to only 8 hours. There is no single phase power supply for remaining hours of the day  this has made their life difficult and they have been persistently demanding at least single phase power supply for rest of the hours.

To overcome above problem and to improve the satisfaction level  a system with a transformer called Specifically Designed Transformer (SDT) was introduced for catering single phase supply where the motive power load shedding is practically difficult due to misuse of the energy by means of unauthorized usage of phase converters. However  while putting in service  the main drawback or limitation in SDT is that one winding terminal out of three terminals is required to be made earthed and hence entire load current amounting up to whatever the capacity of transformer and some times more  passes through earth which leads to take care of high precautions during the erection of earthing and also the periodical maintenance / reactivation of earthing when current passes through earth.

Hence  a system with a single phase transformer with such facility is being extremely needed that could overcome aforesaid difficulties and drawbacks or limitations and would provide a cost effective  maintenance free  safety features and owing to serve in huge demand of power during the planned load shedding.

Object of the invention
The main object of this invention is to provide a system with a planned load shedding transformer of without earthing of any winding terminal which is applicable exclusively applicable in power sector and especially where the motive power load shedding is practically difficult due to misuse of the energy by means of unauthorized usage of phase converters.

Another object of this invention is to provide a system with a highly cost effective  maintenance free and safe planned load shedding transformer. Accordingly  conventional earthing connection and hence huge earthing cost is eliminated using the transformer of the kind used in the invention.

Another object of the invention is to provide a system with a planned load shedding transformer that owing to serve in huge demand of power and that maintains steady current intensity for any nominal value of the voltage supplied.

Further object of this invention is to concern a system with planned load shedding variable transformer though which absolute continuous output voltage is achieved without any gaps-voids during the load shedding period.

Still further object of this invention is to provide a system with a planned load shedding transformer that provides energy conservation by around 30% in normal lighting surveillance and also provides reduction in no load losses of the distribution transformer by around 66%. Saving of energy by eliminating misuse of energy using phase converter at the approximate amount of around 90%.

Summary of the Invention
The present invention relates to a system with a planned load shedding transformer of without earth with vision of supplying 24 X 7 hours power supply to consumers located in agriculture areas during the period of planned load shedding on agriculture feeders  with restriction on misuse of electricity using phase converter. Such transformers are likely to be installed in the 33/11  66/11& 132/11 KV substation at the sending end of the feeder which delivers power to the high tension side of the distribution transformer. The system includes a planned load shedding transformer  a gang operated change over switch  a high tension current transformer and an IDMT (Inverse Define Minimum Time) relay. The system is connected between any two phases of conventional substation power transformer. By operating the gang operated change over switch in one position three phase power supply is fed to the feeder which enables to charge primary delta winding for high tension side of the entire DY 11 distribution transformer. Whereas  operating said gang operated change over switch in another position two phase supply is fed to the single phase load shedding transformer which in turn appears in the circuit and feeds single phase power to entire consumers on agriculture dominant feeder for single phase lighting use.

Detail description of the drawings
Fig. 1 illustrates an elevation view of planned load shedding transformer for the system of present invention.

Fig. 2 illustrates a side view of planned load shedding transformer for the system of present invention.

Fig. 3 illustrates a plan view of planned load shedding transformer for the system of present invention.

Fig. 4 illustrates a schematic diagram for planned load shedding transformer for the system of present invention showing 11 KV Feeder (23) and 11 KV outgoing cable (24) from Sub Station.

Fig. 5 illustrates a schematic line diagram for planned load shedding transformer for the system of present invention with set of three lightening arrester (25) and using HT CT & 11 KV change over switch.

Fig. 6 illustrates a schematic diagram for the three different terminals brought out from the primary and secondary winding arrangements of the single phase planned load shedding transformer.

Hereinafter  an exemplary embodiment of the present invention will be described with reference to the accompanying drawings. In the following description  the same elements will be designated by the same reference numerals although they may be shown different in drawings. Further  in the following description of the present invention  a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Detail description of the invention
The present invention relates to a system for supplying 24 X 7 hours power supply to consumers located in agriculture areas during the period of planned load shedding on agriculture feeders for energy conservation system  with restriction on misuse of electricity using phase converter. The system includes a planned load shedding transformer (18) for supplying single phase power supply during the planned load shedding  a gang operated change over switch (20)  a high tension current transformer (19) of 11 KV class and an IDMT relay. The system which is installed on double pole structure is connected between any two phases of conventional substation power transformer. Entire system is installed in Sub Station only  means it remains within the control of power supply utility. It is installed at the sending end of a feeder only  and the remaining portion of the network remains unaltered  with required results.

As directed in Fig. 1  2 and 3  said planned load shedding transformer (18) consists of internal active parts and conventional inactive parts and said inactive parts works as a container of all internal active parts. Said inactive parts includes a sampling valve (1)  a conservator tank (2)  an oil level gauge (3)  a pair of tank lifting lug (4)  a rating and diagram plate (5)  a transformer tank (6)  a pair of earthing terminals (7)  a pair of base channels (8)  a silica gel breather (9)  a thermometer pocket (10)  a pair of lifting lug for active part (11)  a set of three high voltage bushings (12)  cooling radiators (13)  an explosion vent (14)  an air release plug (15)  a pair of pulling lug (16) and a set of three arcing horn (17). Normally  a conventional distribution Transformer consists of three High Voltage (11 / 22 KV) bushings and four Low Voltage (433v) bushings  where as  in the present transformer (18) for energy conservation system  there are only three numbers of High Voltage bushings (12kV).

Said active parts of planned load shedding transformer (18) includes a primary and secondary windings a three / two legged core onto which said primary and secondary windings are wounded; and a transformer oil. Said primary as well as secondary windings are of aluminum or copper wound and is distributed in various coils and assembled in ""sandwich""  or ‘up down’ configuration from which three different terminals R (In/Out)  Y (Out) and B (In) were brought out as directed in Fig. 6. In which the terminal R (In/Out) is connected with primary windings as well as secondary windings (26); and whereas B (In) and Y (Out) are respectively connected to primary windings and secondary windings (26). The core is either CRGO (Cold Rolled Grain Oriented Silicon Steel) or Amorphous. The turns ratio of the transformer (18) is the ratio of the number of turns of its both primary as well as secondary windings divided by the number of turns of the secondary winding (26). The turns ratio is equivalent to the step up or step down voltage ratio of the transformer (18). By measuring the turns ratio of the transformer (18) from its performance and comparing this with its rated voltage a good indication of the condition of the transformer (18) can be obtained.

The gang operated changeover switch (20) is placed in the circuit as shown in the diagram Fig. 4 & 5. Application of the present system is explained in Fig. 4. In Fig. 4  schematic diagram connections for planned load shedding transformer (18) for the said system using high tension current transformer (19). By operating the gang operated change over switch (20) in one position three phase power supply is fed to the feeder which enables to charge primary delta winding for high tension side of all the DY 11 distribution transformer (21) by isolating the connection of planned load shedding transformer (18). Whereas  operating said gang operated change over switch (20) in another position two phase supply is fed to the planned load shedding transformer which in turn appears in the circuit and feeds single phase power to all the consumers for single phase lighting use. Said high tension current transformer (19) is kept in the incoming circuit of the planned load shedding transformer (18). Output (22) of said current transformer (19) is fed to an IDMT relay which is separately installed for the system with feeder control panel. This controls the feeder during single phasing.

In the present planned load shedding transformer (18) the voltage ratio is maintained in the range of 10.0 KV to 12.5 KV / 8.5 KV to 11.5 KV  current rating is ranged into above 5 AMP  flux density is from 1.4Wb to 1.75Wb  the normal no load loss is ranged above 50 W  full load losses at 75 deg. C is above 800 W. The Current density used for primary/secondary winding is ranged between 0.5 A/sq.mm to 4.0 A/sq.mm. in the present system clearance between primary & secondary windings are from above 1 mm  secondary & primary coil axial spacers are from above 1 mm  phase - phase is above 1 mm  end insulation clearance to earth is above 1 mm and any point of winding to tank is above 1 mm. the percentage impedance at 75 deg. c is maintained from 1.5 to 6%.

In the present system the length of the single phase planned load shedding transformer (18) is from 400 mm to 1000 mm  breadth is from 250 mm to 600 mm and height is from 700 mm to 1500 mm  Core diameter is from 60 to 180 mm  height of window is from 300 to 900 mm  center-to-center distance of the core is from 100 mm to 500 mm. In the present invention system 1 to 20 secondary & primary coils are provided per limb and the axial length of secondary & primary winding is ranged form 15 mm to 800 mm. Inner and outer diameter of secondary and primary winding are maintained from 80 mm to 200 mm and 100 mm to 400 mm respectively. The total cross section of all conductors of winding is from 0.5 Sq.mm to 15 Sq.mm for primery and 1.5 Sq.mm to 60 Sq.mm for secondary.

While  the invention has been described with respect to the given embodiment  it will be appreciated that many variations  modifications and other applications of the invention may be made. However  it is to be expressly understood that such modifications and adaptations are within the scope of the present invention  as set forth in the following claims.

We Claim 

1. An Energy Conservation System with a planned load shedding transformer a planned load shedding transformer (18) for supplying single phase power supply during the planned load shedding  a high tension current transformer (19) of 11 KV class  an IDMT (Inverse Define Minimum Time) relay and a gang operated change over switch (20) operation which in one position leads to feed three phase power supply to the feeder to charge primary delta winding for high tension side of all the DY 11 distribution transformer (21) and operating said gang operated change over switch in another position leads to feed single phase power to the load shedding transformer (18) and thereby to all the consumers ;

wherein output (22) of said current transformer (19) is fed to an IDMT relay which is separately installed for the system with a feeder control panel;

wherein Said high tension current transformer (19) is kept in the incoming circuit of planned load shedding transformer (18);

wherein said planned load shedding transformer (18) comprises an inactive part and an internal active part;

wherein said inactive part includes a primary as well as secondary winding (26)  a three / two legged core and a transformer oil;

wherein said primary and secondary windings are wounded on said three / two legged core; wherein said winding is made from an aluminum or a copper and is distributed in various coils and assembled in ""sandwich""  or ‘up down’ configuration from which three different terminals R (In/Out)  Y (Out) and B (In) are brought out; wherein the terminal R (In/Out) is connected with primary windings as well as secondary windings (26); and wherein the B (In) and Y (Out) are respectively connected to primary windings and secondary windings (26);

wherein the system is connected between any two phases of conventional substation power transformer.

2. The Energy Conservation System with a planned load shedding transformer as claimed in claim 1  wherein said inactive parts include a sampling valve (1)  a conservator tank (2)  an oil level gauge (3)  a pair of tank lifting lug (4)  a rating and diagram plate (5)  a transformer tank (6)  a pair of earthing terminals (7)  a pair of base channels (8)  a silica gel breather (9)  a thermometer pocket (10)  a pair of lifting lug for active part (11)  a set of three high voltage bushings (12)  cooling radiators (13)  an explosion vent (14)  an air release plug (15)  a pair of pulling lug (16) and a set of three arcing horn (17) and wherein said inactive parts works as a container of all internal active parts.

3. The Energy Conservation System with a planned load shedding transformer as claimed in claim 1  wherein the core is fabricated from either CRGO (Cold Rolled Grain Oriented Silicon Steel) or Amorphous material.

4. The Energy Conservation System with a planned load shedding transformer as claimed in claim 1  wherein the system which is installed on double pole structure.

5. The Energy Conservation System with a planned load shedding transformer as claimed in claim 1  wherein said planned load shedding transformer (18) is installed in the 33/11  66/11 & 132/11 KV substation at the sending end of the feeder which delivers power to the high tension side of the distribution transformer.

6. The Energy Conservation System with planned load shedding transformer as claimed in claim 1  wherein optionally  the planned load shedding transformer is of dry type without oil filled or oil cooled type transformer.

Dated this 20th day of October 2012.