FIELD OF INVENTION
The invention relates to a Circuit Breaker (CB) primarily used to interrupt normal / fault / capacitive / inductive currents of high voltage power transmission and distribution systems.
BACKGROUND OF THE INVENTION& PRIOR ART
When fault current is interrupted by an interrupter, arc is struck between the arcing contacts. The energy content of the arc depends on the current magnitude, length of the arc and similar other parameters. As the temperature of the arc is quite high it decomposes the insulating medium (gas) and materials exposed to arc. Decomposed products accumulate in the vicinity destabilize insulation and shall be removed for sustaining the dielectric properties of the inter-electrode gap for subsequent interruptions.
In conventional interrupters one of the two contacts is fixed, during interruption the moving contact is driven by operating mechanism and an arc is struck on contact separation (Fig.1 (a)). At current-zero the arc is extinguished naturally exposing the developed inter-electrode gap to system and transient recovery voltages. The gap reignites or the arc is re-struck should the gap fail to withstand these voltages. For mechanical constraints limited inter-electrode gaps only can be generated

inconventional interrupters, promoting use of multiple breaks for EHV circuit breakers. Up to 245kV single- break circuit breaker designs are common, beyond this rating two or more breaks are used in series to form a circuit breaker. The multiple breaks require voltage equalizing devices like grading capacitors etc, affecting circuit breaker reliability and cost.
A circuit breaker, in particular a high-voltage circuit breaker, insulated by SF6 gas, comprising, a fixed and the movable arcing contact. The movable arcing contact is integrated with a blast nozzle and is actuated by a drive. The SF6 gas compression volume being decreased during the process of interruption such that a flow of the SF6 gas is directed by the blast nozzle toward the arc being produced.
In general, to limit the voltage appearing across the contacts during interruption, multiple breaks are preferred. The multiple break system is operated by same drive which requires higher energy drive for its operation. To overcome this problem, a dual motion contact system has been identified as an alternative solution. However, in all these systems, the second movable contact i.e., other than primary moving contact takes sufficient portion of energy from the operating mechanism. In some of the conventional breakers, grounded enclosures are mounted horizontally (US 5736704 A).The pole comprises two gas-tight insulated bushings respectively connected, inside the enclosure, to fixed contact and to the movable contact.

Movable contact actuated by an operating rod passing through the enclosure in a gastight manner and connected, outside the enclosure, to an operating mechanism. Some times in horizontally mounted circuit breakers also, mechanism is provided from the side and operated through rotational shaft arrangement (US 5750949 A). In some of the conventional breakers, a grounded enclosure side main rotating shaft connected to said movable contact system through a connection member(US 6407908 B1). This side main rotating shaft is connected to operating drive. This type of arrangement requires lot of couplings, friction and hence there is a possibility of loss of available energy from the drive. Fig.1 shows the conventional horizontally mounted circuit breaker. For successful interruption, the primary design requirements are: frictionless moving contact system, easily maintainable system and shall be single break system.
OBJECTS OF THE INVENTION
The main object of the invention is to improve interrupting performance of higher voltage circuit breakers through execution of other objectives as under:
• Reduction of breaks per pole for circuit breakers of higher voltage class.
• Vertically mounted gas circuit breaker
• Efficient discharge of hot arced gas.

• Linearly operating drive for gas circuit breaker
• Linearly operated coupling between drive and interrupter
• Provision for measurement of speed-travel characteristics
• Mechanical support of the pole through novel interrupter enclosure.
• Interface housing between interrupter enclosure and operating drive
• Guided movement of insulated operating rod.
• Linearly operating insulated operating rod
• CB Enclosure with multiple ports to commensurate to other modules of switchgear
• Provision to isolate interrupter enclosure with interrupter pole from operating drive.
SUMMARY OF THE INVENTION
The present invention is directed to improve the gas interrupter performance both in terms of interrupting capacity and dielectric recovery with due consideration to the following:
1. Housing for interrupter pole
2. Integration of interrupter pole and operating drive.
3. Achieving highest possible speeds with linearly coupling system between insulated operating rod and drive.

4. Vertically mounted interrupter with linearly operating drive.
5. Efficient discharge of arced gas
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The invention is described with the help of Figures 1 to 7, where:
Figure 1: Conventional Enclosures of gas circuit breakers.
Figure 2: Moving contact assembly
Figure 3: Guide support for insulated operating rod
Figure 4: Coupling between insulated operated rod and Operating drive
Figure 5: Operating terminal for measuring speed-travel characteristics.
Figure 6: Interrupter Housing with support insulators
Figure 7: Vertically mounted interrupter with operating drive.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION
A gas-insulated circuit breaker consisting of vertically mounted interrupter and linearly operating drive with appropriate coupling element. The interrupter pole is insulated from grounded enclosure with compressed SF6 gas. The arcing contacts are mainly fixed movable contact and movable arcing contact. In the present

invention, the socket [01], made of a high conductivity and low erosion material is held on a socket support [02]. The socket is covered by aan insulating shroud [03] made from filled PTFE material. The nozzle [05] is fixed to dynamic current carrying (CC) contact [04] and to the socket contact assembly. The socket [01], insulating shroud [03] and current carrying contact [04] are termed as the socket contact assembly. The insulating shroud consists of radial holes to reduce the diameter of arcing column. The socket [01], insulating shroud [03] and current carrying contact [04] along with flap housing [06] form the thermal volume of the breaker.
The movable arcing contact system consists of current carrying contact [04] integrated with insulated nozzle [05] and blast cylinder (compression volume [07]). The compression volume [07] is isolated from current carrying contact [04] with non-returnable valve (valve which opens only when pressure in compression volume is more than expansion volume). Fig. 2 shows the moving contact assembly. The moveable contact system is being operated by insulated operating rod [08] and is guided by using guide housing [09] located in mechanism housing [10]. The insulated operating rod [08] is connected from movable contact system through metallic pull tube [11] which is also used to exhaust hot arced gas. Primarily the movable contact system with metallic pull tube [11] is guided through piston housing and piston support [12]. The insulated operating rod [08]is connected to operating drive [13] through adapter [14] which has provision for guiding [15] the

insulated operating rod [08]. The adapter [14] is designed in such a way that it shall not hamper speed of the operating drive [13]. The adapter [14] dimensions are so close to guide housing [09] to ensure frictionless movement of contact system. The adapter [14] is a circular plate and has Teflon/insulated ring [15] to move against guide housing [09]. The circular plate / adapter [14] has slots to communicate gas from interrupter to operating drive side and the slot area shall be so high that gas pressure does not build under the adapter [14] during opening operation. The adapter [14] shall be made of light weight metal like Aluminum to limit the weight of moving mass. Fig. 3 shows the guide support for insulated operating rod assembly. Further, it is important to maintain gas communication between interrupter housing [16] and mechanism housing [10] (at the bottom of the guide housing) to overcome the problem of speed limitation. The insulated operating rod [08] connected to metallic rod [17A] through adapter [14] shall be clamped to operating rod [17B] of drive [13] through a Coupler [18] which can adjust misalignment. The mechanism housing has two main functions: one is to support interrupter pole through support plate [19]. Second one is to hold guide housing [09] to guide moving contact system connected to insulated operating rod [08]. This housing shall be filled with SF6 gas and isolated from environment through dynamic seal [20].
The coupler [18] is facilitated with a terminal [21] to mount travel recorder [22] which can move vertical direction. The coupler [18] shall be placed outside gas

environment and in a chamber called as spacer assembly [23]. Fig. 4 shows the coupling between insulated operating rod and operating drive. The spacer assembly [23] is located in outside environment and insulated from SF6 gas filled mechanism housing through dynamic seal [20]. The spacer assembly [23] is basically a four-way system, top side is connected to mechanism housing [10], bottom side is connected to operating drive [13]. Left/right side of spacer assembly has provision for travel recorder [22] and right/left side has provision for man hole. The terminal [21] shall be routed through plate which has guide [24] to establish frictionless movement of terminal [21]. The same is used to mount travel recorder [22]. Other end of the travel recorder is connected to mechanism housing [10] through support plate. The travel recorder mounted here can be connected any time to monitor speed characteristics during service. The spacer assembly [23] height shall be decided by stroke length. The travel recorder and insulated operating rod [08] operate in vertical direction and further has linear movement only. Fig. 5 shows the view of operating terminal for measuring speed-travel characteristics.
Vertically mounted interrupter housing has to facilitate support to the pole both at bottom and top side of it. The pole is supported on mechanism housing [10] which is integrated to interrupter housing [16] through support plate [25]. Bottom side of pole is again supported from interrupter housing [16] with epoxy support insulator [26]. Top side of pole is guided from housing through epoxy insulator [26]. Top side

of housing has two ports, either of one is used to support the pole by insulator [26]. Sometimes both the ports at top can be used to connect to other modules of GIS like current transformer, maintenance earthing switch etc. In this case pole is supported by two epoxy support insulators [26].Top most port of housing [27]is used as man hole. The surface on which top most port is made is dish / spherical type to achieve more surface area for cooling and to hold for high pressures. The ports are projected out from housing to such a distance that support insulator shall be within extension. The top most and bottom most ports are designed in such a way that the diameter/bay width is optimized to the extent that design parameters met. Figure 6 shows the interrupter housing with support insulators.
Interrupter pole is divided into two parts. One is bottom pole or static pole and other is top pole or dynamic pole. The bottom pole consists of support insulator [28], arcing insulator [29], insulated operating rod [08], piston assembly [30] and housing for arced gas exhaust [31].Support insulator [28] is used to support piston assembly [30] and housing for arced gas exhaust [31].The openings of piston assembly [30], metallic pull tube [11] and housing for arced gas exhaust [31] shall be matched to ensure 100% discharge of arced gas effectively. One more function of support insulator [28] is to support high voltage connection (second terminal) of circuit breaker. Support insulator has two terminals, one is high voltage bus terminal and second one is high voltage feeder/incomer terminal. The insulated operating rod

[08] is located coaxially inside support insulator [28] in such a way that, electrostatic field across insulating operating rod [08] is lowest in all the possible positions of the drive (both open, close and during close-open). The arcing insulator [29] is also supported by support insulator [28]. The arcing insulator further supports fixed current carrying contact system and guide the moving arcing system. The piston which creates pressure in compression cylinder is connected to housing [31] through which movable arcing system is guided. This housing is to facilitate for the discharge of arced gas and to support / guide the bottom pole from grounded enclosure through insulator. One more objective of present patent is to provide adjustable coupling [32] from breaker pole to terminals of breaker [33] as it requires high quality manufacturing to achieve linear and angular accuracy. Integration of housing to insulator has flexible connection to facilitate height adjustments and at the same time to offer lowest possible resistance. The proposed coupling element [32] is adjustable in both directions and transfers current effectively from / to the circuit breaker pole. This is achieved by using adjustable spacers [34] on either side of coupling element. This coupling is effective for higher fault currents of and higher rated currents of few thousands of amperes. This coupling element [32] consists of cylindrical member of rotatable type with current transfer contacts. This coupling transfers current from dual motion mechanism housing of top pole [35] or housing for arced gas exhaust [31] of bottom pole to circuit breaker terminal [33].

The top pole consists of moving arcing contact system [01-05], compression volume [07], movable fixed contact system [36], dual motion mechanism [35], housing for exhaust of arced gas[37] and metallic pull tube [11].The top pole is supported from grounded enclosure through support insulator [26]. The top pole is connected to bottom pole assembly through easily accessible link. Figure 7 shows the vertically mounted gas insulated interrupter with drive.

WE CLAIM
1. A vertically mounted high voltage gas circuit breaker (100) comprising, a vertically mounted single break interrupter in a novel housing with optimized ports, characterized by,
- integration of interrupter housing with mechanism housing
- integration of interrupter with operating drive
- integration of interrupter pole with mechanism housing and operating drive
- movable contact system with metallic pull tube guided through piston support
- linear coupling between insulating operating rod and vertically operative drive
- guiding insulated operating rod and piston maintaining high speed characteristics
- gas communication between mechanism housing and interrupter pole
- linearly operating travel recorder
- on-line measurement of travel speed characteristics
- integration of travel recorder to coupling link between operating drive and insulated operating rod.

2. The circuit breaker as claimed in claim 1, wherein the moving contact assembly, comprising the socket (01) held on a socket support (02) covered by a insulating shroud (03), the nozzle (05), fixed to dynamic current carrying contact (04) and to the socket contact assembly, characterized by the insulating shroud with radial holes reducing diameter of arcing column.
3. The moving contact assembly as claimed in claim 2, wherein the arcing contact system, comprising current carrying contact (04) integrated with insulated nozzle (05) and the blast cylinder (compression volume)(07), characterized by, compression volume (07) being isolated from current carrying contact with non-returnable valve opening only when pressure in compression volume is more than the expansion volume.
4. The moving contact assembly as claimed in claim 2, wherein the insulated operating rod (08) guided by the guide housing (09) and piston support (12) connected from the movable contact system through metallic pull tube (11) is connected to operating drive (13) through adapter (14), characterized by the dimensions of the adapter(14) as being so close to guide housing (09) ensuring frictionless movement of the contact system.

5. The circular plate/adapter (14) as claimed in claim 4, having Teflon ring (15) and slots to communicate gas from interrupter to operating drive side, characterized by high slot area to restrict pressure under the adapter during opening operation maintaining gas communication between interrupter housing (16) and mechanism housing (10) overcoming speed limitation.
6. The insulated operating rod as claimed in claim 4, connected with metallic rod (17A) and clamped to operating rod (17B) of drive (13) through coupler (18).
7. The circuit breaker as claimed in claim 1, wherein, the mechanism housing (10) filled with SF6 gas and isolated from environment through dynamic seal (20) supports interrupter pole through support plate (19) and hold guide housing (09) to guide moving contact system.
8. The coupler (18) as claimed in claim 6 ,facilitated with terminal (21) to mount travel recorder (22), placed in spacer chamber assembly (23), adjusts misalignment, if any.
9. The spacer assembly (23) as claimed in claim 8, insulated from mechanism housing through dynamic seal (20), is a four way system, top side connected to mechanism housing (10), bottom side connected to operating drive (13), travel

recorder (22) provided on left side, and provision for man-hole on the right.
10.The circuit breaker as claimed in claim 1, wherein the interrupter housing (16) with support insulator (28) comprising two poles, one located at the bottom is a static pole, and other at the top is dynamic pole.
11.The interrupter housing (16) as claimed in claim 10, wherein the bottom pole comprising support insulator (28), arcing insulator (29), insulated operating rod (08), piston assembly (30), housing for arced gas exhaust (31), characterized by exact matching of components to ensure complete discharge of arced gas.
12.The interrupter housing along with the pole as claimed in claim 11, wherein adjustable coupling (32) along with adjustable spacers (34) , characterized by their adjustability on either side of the coupling element for higher fault currents.
13.The coupling element as claimed in claim 12, comprising of rotatable cylindrical member having current transfer contacts, transfers current from dual motion mechanism housing of top pole(35) or housing for arced gas exhaust (31) of bottom pole to circuit breaker terminal (33).

14.The interrupter housing as claimed in claim 11, wherein the top pole comprising moving arcing contact system (01-05), compression volume (07), movable fixed contact system(36), dual motion mechanism (35), housing for exhaust arced gas (37), metallic tube (11), supported from grounded enclosure through support insulator (26) is connected to bottom pole through accessible link.