Description:TECHNICAL FIELD
[0001] The present disclosure relates, in general, to gas-insulated switchgear, and more specifically, relates to a support arrangement of the potential transformer.

BACKGROUND
[0002] In switchgear, monitoring power frequency system voltage is very important. To monitor the power quality of a system, a potential transformer plays an important role. Previously in the gas-insulated switchgear (GIS) panel, the potential transformer (PT) is generally supported with the potential transformer support bracket which is mounted on the cable chamber assembly. The weight of the overall panel would lead to the bulging of the side sheet of the cable chamber which in turn is resulting in the displacement of the potential transformer support bracket. This displacement of the potential transformer support bracket could lead to misalignment of the potential transformer causing air gaps between the potential transformer and bushing. This development of air gaps is a crucial problem leading to tracking, arcing, and ultimately resulting in flashover. Hence, the new support displacement-free arrangement of potential transformers in gas-insulated switchgear is crucial.
[0003] Therefore, it is desired to overcome the drawbacks, shortcomings, and limitations associated with existing solutions, and develop a cost-effective support arrangement that is ergonomic in design and easy to assemble and disassemble.

OBJECTS OF THE PRESENT DISCLOSURE
[0004] An object of the present disclosure relates, in general, to gas-insulated switchgear, and more specifically, relates to a support arrangement of the potential transformer.
[0005] Another object of the present disclosure is to provide a support arrangement having a unique design and working philosophy of potential transformer support arrangement.
[0006] Another object of the present disclosure is to provide a support arrangement that is ergonomic in design and easy to assemble and disassemble as very few parts are involved.
[0007] Another object of the present disclosure is to provide a support arrangement that is a less costly and less sophisticated arrangement for this application.
[0008] Another object of the present disclosure is to provide a support arrangement in which two-thirds of components are standard, where they remain the same irrespective of potential transformer weight.
[0009] Another object of the present disclosure is to provide a support arrangement to ensure the potential transformer plate and tank bottom sheet are properly flushed and there is no air gap.
[0010] Yet another object of the present disclosure is to provide a support arrangement, where each potential transformer have its supporting arrangement so high flexibility in adjusting the positions of individual potential transformer irrespective of other ones is achieved.

SUMMARY
[0011] The present disclosure relates in general, to gas-insulated switchgear, and more specifically, relates to a support arrangement of the potential transformer. The main objective of the present disclosure is to overcome the drawback, limitations, and shortcomings of the existing arrangement and solution, by providing a support arrangement of the potential transformer which can be used in the metal-clad enclosure of GAS-insulated switchgear. The potential transformer is an instrument transformer that is employed in a power system for measurement and protection purposes. The potential transformer is used to measure high alternating voltage in a power system. A dielectric failure could occur if there is an air gap between the PT and the type-2 inner cone bushing. Hence, the present disclosure provides supporting arrangements to PT is very crucial.
[0012] The support arrangement of the potential transformer in gas-insulated switchgear includes the support bracket of the potential transformer that is mounted on a cable chamber. The plug flange is accommodated in the welded assembly of tank, the plug flange is adapted to support the potential transformer. The plug flange having clear holes at the top side and threaded holes at the bottom section. The plug flange have six per phase at a pitch of clear hole of 60 degrees on the top side to accommodate type-2 inner cone bushing and 4 per phase threaded holes to accommodate mounting stud of the potential transformer.
[0013] The mounting stud is accommodated on the plug flange, further, a bottom support plate is fixed to the mounting stud, where the cut-out is provided on the bottom support plate for secondary winding wiring so as to restrict the upward and downward motion and to and fro motion of the potential transformer keeping it firm on its position. Moreover, the bottom support plate is tightened to provide contact pressure to avoid the development of air gaps between the potential transformer and the type-2 inner cone bushing.
[0014] Further, the plug flange have a thickness of 12mm-20mm depending upon the weight of the potential transformer. The depth of the threaded holes varies from 7.5mm to 15.5mm depending upon the weight of the potential transformer. The type-2 inner cone bushing is fixed after welding the plug flange to the bottom sheet of the tank. The thickness and length of the bottom support plate are selected based on the weight of the potential transformer. The hex cuts are accommodated on the mounting stud for ease of assembly.
[0015] The support arrangement is a less costly, less sophisticated arrangement for this application. The support arrangement in which two-thirds of components are standard, where they remain the same irrespective of potential transformer weight. The support arrangement is accessible to ensure the potential transformer plate and tank bottom sheet are properly flushed and there is no air gap. Each potential transformer has its supporting arrangement so high flexibility in adjusting the positions of individual potential transformers irrespective of other ones is achieved.
[0016] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The following drawings form part of the present specification and are included to further illustrate aspects of the present disclosure. The disclosure may be better understood by reference to the drawings in combination with the detailed description of the specific embodiments presented herein.
[0018] FIG. 1 illustrates an exemplary general support arrangement of a potential transformer in gas-insulated switchgear, in accordance with an embodiment of the present disclosure.
[0019] FIG. 2 illustrates exemplary top-face clear holes and bottom-face threaded holes on the plug flange, in accordance with an embodiment of the present disclosure.
[0020] FIG. 3 illustrates an improved potential transformer support arrangement, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION
[0021] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.
[0022] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0023] The present disclosure relates, in general, to gas-insulated switchgear, and more specifically, relates to a support arrangement of the potential transformer.
[0024] The proposed support arrangement disclosed in the present disclosure overcomes the drawbacks, shortcomings, and limitations associated with the conventional arrangement by providing a support arrangement of the potential transformer, which can be used in the metal-clad enclosure of GAS-insulated switchgear. The potential transformer is an instrument transformer that is employed in a power system for measurement and protection purposes. The potential transformer is used to measure high alternating voltage in a power system. A dielectric failure could occur if there is an air gap between the PT and the type-2 inner cone bushing. The present disclosure can be described in enabling detail in the following examples, which may represent more than one embodiment of the present disclosure.
[0025] The advantages achieved by the potential transformer of the present disclosure can be clear from the embodiments provided herein. The support arrangement having a unique design and working philosophy of PT support arrangement. The support arrangement is ergonomic in design, and easy to assemble and disassemble as very few parts are involved. The support arrangement is less costly and less sophisticated arrangement for this application. The support arrangement in which two-thirds of components are standard, where they remain the same irrespective of PT weight. The support arrangement is accessible from the front side to ensure the PT plate and tank bottom sheet are properly flushed and there is no air gap.
[0026] Further, the support arrangement, where each PT have its supporting arrangement so high flexibility in adjusting the positions of individual PT irrespective of other ones. The description of terms and features related to the present disclosure shall be clear from the embodiments that are illustrated and described; however, the invention is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents of the embodiments are possible within the scope of the present disclosure. Additionally, the invention can include other embodiments that are within the scope of the claims but are not described in detail with respect to the following description.
[0027] FIG. 1 illustrates an exemplary general support arrangement of a potential transformer in gas-insulated switchgear, in accordance with an embodiment of the present disclosure.
[0028] Referring to FIG. 1, the support arrangement of potential transformer 100 in gas-insulated switchgear is disclosed. The support arrangement of the potential transformer can be used in a metal-clad enclosure of the gas-insulated switchgear. The potential transformer 100 is an instrument transformer that is employed in a power system for measurement and protection purposes. The potential transformer 100 is used to measure high alternating voltage in the power system. The dielectric failure could occur if there is an air gap between the potential transformer 100 and the type-2 inner cone bushing 302. The potential transformer 100 for metal-clad switchgear is racked into and out of a switchgear cubicle to connect and disconnect the potential transformer to a line.
[0029] The potential transformer 100 can include type-2 inner cone bushing 302, PT support bracket 104, cable chamber 106, side sheet 108, PT plug flange 112, tank bottom sheet 110, PT mounting stud 306 and bottom support plate 308 shown in FIG. 3. The support arrangement is provided with specially designed potential transformer plug flange 112 made to support the potential transformer. The potential transformer plug flange 112 have thickness of 12mm-20mm depending upon the weight of the potential transformer. The potential transformer plug flange 112 is welded with tank bottom sheet 110.
[0030] The support arrangement of the potential transformer in gas-insulated switchgear, the support arrangement can include the support bracket 104 of the potential transformer 100 that is mounted on a cable chamber 106. The plug flange 112 is accommodated in the welded assembly of tank, the plug flange 112 is adapted to support the potential transformer. The mounting stud 306 is accommodated on the plug flange 112, further, a bottom support plate 308 is fixed to the mounting stud 306, where the cut-out is provided on the bottom support plate 308 for secondary winding wiring so as to restrict the upward and downward motion and to and fro motion of the potential transformer keeping it firm on its position. Moreover, the bottom support plate 308 is tightened to provide contact pressure to avoid the development of air gaps between the potential transformer 100 and the type 2 inner cone bushing 302.
[0031] The plug flange 112 having clear holes at the top side and threaded holes at the bottom section. The plug flange 112 have six per phase at a pitch of clear hole of 60 degrees on the top side to accommodate type-2 inner cone bushing 302 and 4 per phase threaded holes to accommodate mounting stud 306 of the potential transformer. The mounting stud 306 is assembled in the threaded holes and the bottom support plate 308 is fixed to the mounting stud 306.
[0032] The plug flange 112 have thickness of 12mm-20mm depending upon the weight of the potential transformer. The depth of the threaded holes varies from 7.5mm to 15.5mm depending upon the weight of the potential transformer. The type-2 inner cone bushing 302 is fixed after welding the plug flange 112 to a bottom sheet of tank 304. The thickness and length of the bottom support plate 308 are selected based on the weight of the potential transformer. The hex cuts are accommodated on the mounting stud 306 for ease of assembly.
[0033] FIG. 2 illustrates exemplary top-face clear holes and bottom-face threaded holes on plug flange, in accordance with an embodiment of the present disclosure.
[0034] As shown in the FIG 2, the potential transformer plug flange 112 have six per phase M10-M12 at a pitch of clear hole 60 degrees on the top side to mount type-2 inner cone bushing 302 and 4 per phase threaded holes to mount the PT mounting stud 306. The depth of the threaded holes may vary from 7.5mm to 15.5mm depending upon the weight of the potential transformer. The type-2 inner cone bushing 302 is fixed after welding the PT plug flange 112 to the bottom sheet of tank 304.
[0035] The plug flange 112 having clear holes at the top side 202 and threaded holes at the bottom side 204. Once the bushing 302 is mounted, outer cone of the PT is inserted in the busing. Then, PT mounting stud 306 is assembled in the threaded holes and after this bottom support plate 308 is fixed.
[0036] FIG. 3 illustrates an improved potential transformer support arrangement, in accordance with an embodiment of the present disclosure. The thickness and length of the bottom support plate 308 are chosen keeping in mind the weight of the potential transformer. A cut-out is provided on the bottom support plate 308 for secondary winding wiring. This restricts the up and down as well as to and fro motion of PT keeping it firm on its position. Also, tightening of bottom support plate 308 provides enough contact pressure to avoid the development of air gaps. Hex cuts on the studs 306 are provided for ease of assembly as it can easily hold them through a spanner.
[0037] Thus, the present invention overcomes the drawbacks, shortcomings, and limitations associated with existing solutions, and provides a unique design and working philosophy of PT support arrangement. The PT support arrangement is ergonomic in design and easy to assemble and disassemble as very few parts are involved. The PT support arrangement is less costly, less sophisticated arrangement for this application. The PT support arrangement in which two-thirds of components are standard, where they remain the same irrespective of PT weight. Each PT has its own supporting arrangement so high flexibility in adjusting the positions of individual PT irrespective of other ones.
[0038] It will be apparent to those skilled in the art that the potential transformer 100 of the disclosure may be provided using some or all of the mentioned features and components without departing from the scope of the present disclosure. While various embodiments of the present disclosure have been illustrated and described herein, it will be clear that the disclosure is not limited to these embodiments only. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the disclosure, as described in the claims.

ADVANTAGES OF THE PRESENT INVENTION
[0039] The present invention provides a unique design and working philosophy of PT support arrangement.
[0040] The present invention provides a support arrangement that is ergonomic in design and easy to assemble and dissemble as very few parts are involved.
[0041] The present invention provides a support arrangement that is less costly, less sophisticated arrangement for this application.
[0042] The present invention provides a support arrangement in which two-thirds of components are standard, where they remain the same irrespective of PT weight.
[0043] The present invention provides a potential transformer where each PT have its own supporting arrangement so high flexibility in adjusting the positions of individual PT irrespective of other ones.

, Claims:1. A support arrangement (100) of potential transformer in gas-insulated switchgear, the support arrangement comprising:
a support bracket (104) of the potential transformer is mounted on a cable chamber (106);
a plug flange (112) accommodated in welded assembly of tank, the plug flange is adapted to support the potential transformer; and
a mounting stud (306) is accommodated on the plug flange, a bottom support plate (308) is fixed to the mounting stud (306), wherein cut-out is provided on the bottom support plate for secondary winding wiring so as to restrict the upward and downward motion and to and fro motion of the potential transformer keeping it firm on its position, and wherein the bottom support plate is tightened to provide contact pressure to avoid the development of air gaps.
2. The support arrangement as claimed in claim 1, wherein the plug flange (112) having clear holes at top side (202) and threaded holes at the bottom side (204).
3. The support arrangement as claimed in claim 2, wherein the plug flange (112) have six per phase at a pitch of clear hole of 60 degrees on the top side to accommodate type-2 inner cone bushing (302) and 4 per phase threaded holes to accommodate the mounting stud (306) of the potential transformer.
4. The support arrangement as claimed in claim 1, wherein the mounting stud (306) are assembled in the threaded holes and the bottom support plate (308) is fixed to the mounting stud (306).
5. The support arrangement as claimed in claim 1, wherein the plug flange (112) have thickness of 12mm-20mm depending upon the weight of the potential transformer.
6. The support arrangement as claimed in claim 1, wherein the depth of the threaded holes vary from 7.5mm to 15.5mm depending upon the weight of the potential transformer.
7. The support arrangement as claimed in claim 1, wherein the type-2 inner cone bushing (302) is fixed after welding of the plug flange (112) to a bottom sheet of tank (304).
8. The support arrangement as claimed in claim 1, wherein the thickness and length of the bottom support plate (308) are selected based on the weight of the potential transformer.
9. The support arrangement as claimed in claim 1, wherein hex cuts are accommodated on the mounting stud (306) for ease of assembly.