FIELD OF THE INVENTION:

The present invention relates to integration of three phase Gas insulated Switchgear Bay of a particular design with any type of Gas insulated bus configuration. The invention specifically proposed a novel integration of single bus / double bus of any orientation or of any phase distance with gas insulated switchgear bay and concept of necessary modules and design thereof.
BACKGROUND OF THE INVENTION
The three phase gas insulated bus bar module is used to interconnect three phase electric power systems. This bus bar module shall also make the inter connection between different three phase gas insulated modules. The gas insulated bus bar module consists a metallic chamber filled with insulating gas and has need-based multiple ports and are located at a pre-defined angle.
The three phase gas insulated bus bar module consists of three independent bus bar modules with pre-defined phase distances. Each bus bar module consists a metallic chamber filled with SF6 gas and the bus bar is supported by a single insulator concentrically. The angularly oriented gas insulated modules are required to integrate three phase gas insulated bus bar arrangement of any configuration to the gas insulated switchgear of any type of configuration. The angularly oriented gas insulated modules are further required to provide safe working clearances for the rated / test voltages and are essential for efficient current transfer from bus bar to GIS bay. In practical electric power systems, it is often required to integrate the new gas insulated switchgear bays with existing gas insulated bus. In such circumstances there is a need of suitable system to interconnect those two electric systems.

Prior art:
The present invention relates to three phase gas insulated switchgear, particularly integration of three phase bus bar module to the gas insulated switchgear bay. In conventional systems, gas insulated switchgear bay is connected to gas insulated bus bar directly as direct connection possible and system can be made compact. In practical electric power systems, it is often required to integrate the new gas insulated switchgear system with existing gas insulated bus. In such circumstances there is a need of suitable system which shall interconnect these two electric systems.
To integrate such systems, Gas-insulated bus bars are enclosed in a metal encapsulation that is filled with an insulating gas, e.g., SF6 or N2 or mixture of these gases or mixture with any other compatible gas. In conventional arrangements, multiple gas insulated modules of arbitrary shaped four-way chamber or three-way chamber are used to integrate gas insulated bus bars of existing system configuration to new gas insulated switchgear of different configuration. The interconnecting system shall become bulky and cannot be installed in limited space available in such type of integrations. To provide complete isolation between existing gas insulated bus bar and new gas insulated switchgear, it is difficult to accommodate with standard GIS modules.
In some of the conventional arrangements pat. No. US 5991148, US 8854795B2, US 7911770 B2 and US 2003/0178891A1, various non-standard GIS modules like four-way, three way enclosures and straight enclosures have been used to integrate gas insulated switchgear modules to the gas insulated bus. These modules vary from one substation requirement to another substation requirement. Sometimes, integration further complicates, if gas insulated bus forms part of bus disconnector switch. The present patent aims to address the above problems.

OBJECTS OF THE INVENTION:
1) It is therefore an object of the invention is to propose a compact interconnecting system between existing gas insulated bus bar (bus design 1) and new gas insulated switchgear (GIS design 2).
2) Another object of the invention is to propose high voltage connection from existing bus (bus design 1) to new bus (bus design 2).
3) Another object of the invention is to propose an interface between existing GIS bus and (bus design 1) and new gas insulated switchgear (GIS design 2) in smallest available space and interface system shall be as compact as possible.
4) A still further object of the invention is the proposed interface system shall be suitable for different phase distances of existing bus (bus design 1) and new gas insulated switchgear (GIS design 2).
5) A still further object of the invention is to propose interface system shall be suitable for different configurations of existing double bus (bus design 1) and new gas insulated double bus switchgear (GIS design 2).
SUMMARY OF THE INVENTION
Accordingly, there is provided an interface system shall be of two parts and first one is an interface module between existing gas insulated double bus (Bus design 1) and new bus bar (Bus design 2) (refer Fig. 3) and second one is an interface between new bus bar (Bus design 2) and new gas insulated switchgear (GIS design 2). The concept of interface system [04] shall be suitable for different phase distances of existing bus (bus design 1) and new gas insulated switchgear (refer Fig. 4). Fig. 4 shows the new gas insulated switchgear bay. A novel Angled enclosure of any angle

between 0 to 179 degrees as demanded by the existing bus (bus design 1) configuration is proposed (refer Fig. 5). Novel Angled conductors of any angle between 0 to 179 degrees suit to angled enclosure as demanded by the existing bus (bus design 1) configuration is also proposed (refer Fig. 6).
If proposed gas insulated bus is directly integrated with existing bus through interface module (refer Fig. 3), then the proposed bus has to be integrated with new gas insulated switchgear by means of unique gas insulated modules (refer Fig. 5 and Fig. 9). Further design of this module varies from one phase to another in each gas insulated bus. These modules are angled enclosures from 0 to 179 degrees with straight enclosure on either side. Novel Angled conductors with suitable current transfer half and full bridges (refer Fig. 7) to integrate new Gas insulated switchgear bay module (GIS design 2) and new bus bar (bus design 2). The bus bar module is facilitated with a plug-in feature (refer Fig. 7 and Fig. 8) to integrate to other bus bar with suitable plug-in adapters. The angled bus bar is integration of two conductors i.e. straight conductor [16] and other one is angled cum straight conductor [15]. A concept of integration of angle cum straight conductor [15] with straight conductor [16], through full current transfer bridge [20]. The full current transfer bridge [20] consists of two half current transfer bridges [21]. Each half current transfer bridge [21] has shield [22] to ensure uniform electrostatic field around high voltage conductor (refer Fig. 6 and Fig. 8). The straight conductor [16] and angled cum straight conductor [15] has provision of in built stopper to ensure that the half and full current transfer bridges [20, 21] movement can be restricted. Proposed three phase gas insulated bus bar can be used as gas insulated bus duct or gas insulated transmission line for transmitting electrical power. These interface bend enclosures are compact in nature and the enclosure has similar design on either side of enclosure to commensurate to gas insulated switchgear bay as well as proposed gas insulated bus.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The invention is described with the help of Figures 1 to 9, where:
Figure 1: Conventional arrangements of the Gas insulated switchgear.
Figure 2: Conventional Gas insulated switchgear bay
Figure 3: Interface module between existing gas insulated bus (bus design 1) and
new gas insulated bus (bus design 2) Figure 4: Proposed Gas Insulated switch gear Bay Figure 5: Interface module between new gas insulated bus (bus design 2) and
new gas insulated switchgear (GIS design 2) Figure 6: Novel Angled conductors to integrate new gas insulated bus (bus design
2) and new gas insulated gas insulated switchgear (GIS design 2) Figure 7: Novel Half and full bridge proposed for the integration. Figure 8: Proposed gas insulated bus with termination shield Figure 9: Proposed Interface system between New gas insulated switchgear bay
with Existing Gas insulated bus.
DETAILED DESCRIPTION OF THE INVENTION
A three phase bus consists of three high tension (HT) conductors [01] arranged either in a horizontal row or at vertices of equilateral triangle or in circular configuration. These bus bars are independent phase type and sometimes they are of double bus configuration. Phase to phase distance of these buses [01] are different and they are oriented at different angles. Figure 1 shows conventional gas insulated switchgear arrangements. The present patent covers integration of existing gas insulated substation bays (GIS design 1) with a new design of gas insulated switchgear bay (GIS design 2). Figure 2 shows conventional double bus gas insulated switchgear bay. This integration helps in achieving inter-operability of gas insulated switchgear of one design (GIS design 1) with gas insulated switchgear of another design (GIS

design 2). This integration is of two parts and first one is an interface module between existing gas insulated double bus (Bus design 1) and proposed gas insulated bus bar (Bus design 2) and second one is an interface between new bus bar (Bus design 2) and new gas insulated switchgear (GIS design 2). The interface module is proposed between existing bus (Bus design 1) and new gas insulated bus (bus design 2). In general, they do not match with each other. One more requirement is isolation of gas between two bus bars. The interface module [02] has been made in such a way that, one side it matches to existing bus and another side it matches with proposed new gas insulated bus through non-permeable insulator [03]. The non-permeable insulator [03] is connected to existing gas insulated bus through plug-in connection which is designed based on existing bus design and dimensions. Other side of the non-permeable insulator [03] is connected to new gas insulated bus bar depending on bay width of new gas insulated switchgear bay. Fig. 3 shows the interface system [04] proposed between existing bus (bus design 1) and new gas insulated bus (bus design 2). This bus bar also consists of bellow [05] to take care of thermal expansion or dimensional differences in integration of gas insulated switchgear bay. Three gas insulated bus bars (in case of single bus) or six gas insulated bus bars (in case of double bus) are extended in the same configuration of existing gas insulated bay.
The new gas insulated switchgear bay consists of double bus disconnector switch cum earthing switch [06], circuit breaker [07], current transformer [08], feeder maintenance earthing switch [09], feeder disconnector switch [10], fast acting earthing switch [11], gas insulated bus duct [12] and gas-to-air bushing. All these modules constitute a double bus gas insulated switchgear bay. A particular design of gas insulated switchgear bay has fixed dimensions of bay width, height of the double bus disconnector switches from ground and height of feeder side bus duct. In case of complete gas insulated switchgear configuration of incomer or feeder or bus coupler, the double bus bar generally matches directly to the double disconnector

switch module. Such configurations are very compact and generally when all the bays are of same design. Figure 4 shows the proposed gas insulated switchgear bay (GIS design 2).
If proposed gas insulated bus [12] is same as existing bus [01], then interface module [02] is not required. However, existing bus has to be integrated with new gas insulated switchgear by means of variety of gas insulated modules. Precisely, they are not modular in nature and is not economical. In view of above, it is proposed an interface module between existing bus (bus design 1) and proposed bus (bus design 2). Further design of gas insulated module between proposed bus (bus design 2) and proposed GIS bay (GIS design 2) varies from one phase to another in each gas insulated bus depending on existing bus bar configuration. These modules are angled enclosures [13] from 0 to 179 degrees with straight enclosure on either side. In most of designs it is possible that some of the enclosures are complement to each other. These enclosures are compact in nature and the enclosure has same design on either side to commensurate to gas insulated switchgear bay (GIS design 2) and proposed gas insulated bus (Bus design 2). Figure 5 shows the proposed inter-operable modules. These modules are basically interface module between new GIS bus (bus design 2) and new GIS switchgear bay (GIS design 2). These inter-operable modules also consist of suitable pressure relief valve [14] and pressure gauge to monitor pressure etc. These inter-operable modules consist of straight cum angular conductors [15] with suitable straight conductors [16] and necessary current transfer bridges (refer Figure 5). Here, two types of current transfer bridges are proposed. One is half bridge [17], which is used to integrate straight conductor to the support insulator [18]. This half bridge [17] used along with current carrying shield [19] to transfer current from straight conductor to High tension terminal of support insulator [18]. All angled modules are designed in such a way that only two conductors i.e. straight conductor [16] and other one is angled cum straight conductor [15]. To integrate angle cum straight conductor with straight conductor, full current transfer

bridge [20] is used. The full current transfer bridge [20] consists of two half current transfer bridges [21] in between provision for expansion of conductor (refer Figure 6). Each half current transfer bridge [21] has shield [22] to ensure uniform electrostatic field around high voltage conductor (refer Figure 7). The straight conductor [16] and angled cum straight conductor [15] has provision of in built stopper to ensure that the half and full current transfer bridges [17, 20] does not slide beyond certain extent. Half and full current transfer bridges [17,20] are made of high conductive and flexible material and high voltage shields [19,22] are made of purely high conductive and light material.
Straight cum angled conductors [15] and straight conductors [16] are made of high electrical conductivity material to enable efficient current flow with minimal power loss and is insulated from the grounded metallic enclosure [23] with designed SF6 gas density. The support insulator [18] holds the bus bar [01] through plug-in adapter [24] in such a configuration. Each of the bus bar [12] is ended with termination shield or flexible HT shield [25], which controls the electric stress between the bus bars [12] to the grounded enclosure [23]. Figure 8 shows the bus bar terminated with flexible HT shield. The plug-in adapter [24] is made of high electrical conductivity material makes the electrical connection between support insulator [18] and bus bar [12]. The plug-in-adapter [24] can be alternatively used as current carrying shield [19]. Figure 9 shows the proposed Interface system between New gas insulated switchgear bay with Existing Gas insulated bus.

WE CLAIM

1. A system for integration of existing gas insulated independent/double bus
(bus design 1) with new gas insulated switchgear (GIS design 2)
comprising:-
- existing gas insulated bus (bus design 1) with a new gas insulated bus bar
(bus design 2) by an interface assembly (04) in the first stage and then the proposed gas insulated bus (bus design 2) with a new gas insulated switchgear (GIS design 2) by an interface module (13-22) in the 2nd stage wherein the interface module assembly (04) in first stage of integration comprises interface module (02) disposed between gas insulated (bus design 1) and gas insulated (bus design 2) and further separated by a non-permeable insulator (03) and a further interface module (02) in the 2nd stage of integration is disposed between the new gas insulated bus (bus design 2) and new gas insulated switchgear (GIS design 2), the said interface module (13-22) comprises angled enclosure (13) containing angled cum straight conductor (15), straight conductor (16), pressure relief valve (14), full current transfer bridge (20, 22), the combined integration being made for achieving inter-operability of gas insulated switchgear of one design (GIS design 1) with gas insulated switchgear of another design (GIS design 2).
2. The system as claimed in claim 1, wherein the interface module (02) in the first stage of integration has been made in such a way that one side of it matches to existing bus (bus design 1) and another side matches with the proposed new gas insulated bus (bus design 2) through non-permeable insulator (03).
3. The system as claimed in claim 1, wherein the non-permeable insulator (03) is connected to existing gas insulated bus (01A) through plug in connection (01B) which is designed based on existing bus design and dimension.

4. The system as claimed in claim 3, wherein the other side of the non-permeable insulator (03) is connected to new gas insulated bus bar (01, 01C) depending on bay width of new gas insulated switchgear bay (06-12).
5. The system as claimed in claim 1, wherein the new gas insulated bus (bus design 2) consisting of bellow (05) for taking care of thermal expansion or dimensional differences while integration of gas insulated switchgear bay.
6. The system as claimed in claim 1, wherein for the same configuration of existing gas insulated bay, it consists of three gas insulated bus bars in case of single bus or six gas insulated bus bars in case of double bus.
7. The system as claimed in claim 1, wherein the new gas insulated switchgear bay (06-12) consists of double bus disconnector switch cum earthing switch (06), circuit breaker (07), current transformer (08), feeder maintenance earthing switch (09), feeder disconnector switch (10), fast acting earthing switch (11), gas insulated bus duct (12) and gas to air bushing.
8. The system as claimed in claim 1, wherein the novel Angled enclosure [13] of any angle between 0 to 179 degrees as demanded by the existing bus (bus design 1) configuration is proposed.
9. The system as claimed in claim 1, wherein the Novel Angled conductors (15,16) of any angle between 0 to 179 degrees suit to angled enclosure as demanded by the existing bus (bus design 1) configuration is proposed.
10. The system as claimed in claim 1, wherein the novel Angled conductors (15,16) with suitable current transfer half and full bridges (20,21) to integrate new Gas insulated switchgear bay module and new bus bar (bus design 2).

11. The system as claimed in claim 1, wherein the angled bus bar is integration of two conductors i.e. straight conductor (16) and other one is angled cum straight conductor (15) is proposed.
12. The system as claimed in claim 1, wherein integration of angle cum straight conductor (15) with straight conductor (16), through full current transfer bridge (20) is proposed.
13. The system as claimed in claim 1, wherein each half current transfer bridge (21) has shield (22) to ensure uniform electrostatic field around high voltage conductor.
14. The system as claimed in claim 1, wherein the straight conductor (16) and angled cum straight conductor (15) has provision of in built stopper to ensure that the half and full current transfer bridges (20,21) movement can be restricted.