DESC:TECHNICAL FIELD

[001] The present subject matter described herein, in general, relates to electrical power distribution equipment, such as switchgear, and more particularly to an arc gases/particlesrelief system for protection of electrical compartments and components therein from internal arc fault damage.

BACKGROUND

[002] Arc resistant switchgear enclosures, medium voltage electrical switchgear may include components such as potential transformers (PT), fuses, circuit breakers, but not limited to them. A typical enclosure may have plurality of compartments, with each compartment including one or more electrical components. Such medium voltage electrical components can experience arc faults. An arc fault creates an explosion of hot gasses due to abnormal conditions that releases large amount of arc gases inside switchgear enclosures which may endanger nearby personnel and equipment. Such faults leading to a risk of personal injury, damage and loss of power supply, has increased the demand of enclosures which can clear such faults.

[003] Safety and downtime are the critical factors of any switchgear installation. Considering the above mentioned facts, internal arc fault safety features are also becoming more important in users specification, operation and maintenance of a switchgear installation. Prevention of occurrence of internal arc fault is of utmost importance in a switchgear installation and most important consideration while designing switchgear. An internal arc faults may be rare, in modern, well-conceived, properly planned substations, still it cannot be ruled out completely. An internal arc fault may constitute a hazard if operating personals are present nearby proximity of the switchgear systems. The fault may occur due to the reason such as failure of insulation, contact ageing, system overvoltage’s because of lightning and switching surges, pollution, mal-operation, lack of maintenance of a switchgear and foreign body presence and the like. Although the probability of occurrence of an internal arc fault is low, the impact of such an incidence is devastating. Internal arc fault is the most catastrophic event that can occur in a switchgear installation. When the fault occurs, high thermal energy is released, the temperature heat up and expands the air inside the enclosure and this can exceed the explosion limit. If the overpressure is not contained, the switchgear structure will explode and expel hot gases and particles in the surrounding atmosphere.

[004] Some existing mechanisms to release the hot air gases may include pressure relief flaps at the top of the electric protection enclosure. These flaps are actuated only when high pressure is created inside the enclosure. The existing mechanism also discusses the use of a large opening that connects a device compartment within an enclosure to a vent chamber, with normally closed vent flaps. The vent flaps open to let the arc gasses out of the compartment and into the vent chamber. Such enclosures are designed to direct pressure and hot arc gases that are carried away from switchgear, outside of the substation/building and released to enhance safety. However, the existing pressure venting flaps are structurally heavy which leads to a high value of peak pressure in an electrical compartment before the vent flaps open to exhaust the arc gasses. Also, there could be an external environmental factor which prohibits such apparatus of releasing the hot gases.

[005] Some existing mechanism also discloses an electrical protection enclosure employed with an external arc chambers. A problem with such external arc chambers is that they limit the number and type of the switchgear configurations that may be deployed within a given volume. In addition, certain classes of arc-resistant switchgear systems also require that the pressure and hot arc gases not enter any adjacent enclosures or compartments.

[006] Thus a suitable apparatus is required to diffuse the arc fully or partially and then cool down the hot gases and particles generated due to thermal energy release in such a way that they are no longer be harmful to the operating personal that might be in the near vicinity of the switchgear.

[007] Further, the prior art document, US 5574624 A discloses a ventilation system for arc-resistant switchgear enclosure that provides a cost effective means to collect and channel the pressure and hot exhaust gases from lower compartments and safely vent these gases through the switchgear enclosure.

[008] The prior art document, US 8785770 B2 discloses an arc-resistant switchgear enclosure that is designed so that an arc explosion in any interior compartment is isolated from the remaining interior compartments and vented to the exterior of the enclosure.

[009] Thus, in view of the existing arc venting mechanism for protecting electrical switchgear systems from arc fault explosion, there exist a dire need to provide an improved, cost-effective, and efficient apparatus for ventilation of arc gases and/or particles produced in an electrical switchgear system, so that no damaging effect is produced in the electrical switchgear system.

SUMMARY OF THE INVENTION

[0010] The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the present invention. It is not intended to identify the key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concept of the invention in a simplified form as a prelude to a more detailed description of the invention presented later.

[0011] A primary object of the present invention is to provide an improved, cost-effective, and efficient apparatus for ventilation of arc gases and/or particles produced in an electrical switchgear system by obstructing, deflecting and guiding the hot arc gases and/or particles generated due to thermal energy release, so that no damaging effect is produced in the electrical switchgear system.

[0012] Another object of the present invention is to emit hot arc gases and/or particles generated due to thermal energy release, away from the switchgear installation and from the operating personnel in the near vicinity of the switchgear to a desired location providing no harm to the operator personnel and thereby no damage to the switchgear installation.

[0013] Another object of the present invention is to provide an arc venting apparatus in an electrical switchgear system that withstands higher thermal and mechanical stress during internal arc fault.

[0014] Yet another object of the present invention is to provide an arc venting apparatus that is easy to manufacture and cost effective.

[0015] Another object of the present invention is to provide an arc venting apparatus that enables complete isolation of arc gases and/or particles produced within the compartments, and further facilitate ingress protection to an electrical switchgear device.

[0016] Accordingly, the present invention provides an apparatus for ventilation of arc gases in an electrical switchgear system wherein the apparatus releases hot arc gases and/or particles generated due to thermal energy within the segregated compartments of the electrical switchgear system, by obstructing, guiding and deflecting the arc gases and/or particles outside the electrical switchgear system.

[0017] In one implementation, an electrical switchgear system comprises, an electrical panel having at least one compartment for housing at least one electrical component, andan arc ventingapparatus for releasing arc gases and/or particlesproduced by an electrical arc fault in the compartment, wherein the internal arc venting apparatus further comprises at least one arc flapadapted to provide a path to said arc gases and/or particles, at least one arc deflectors adapted to channelize, deflect and guide said arc gases and/or particles received from the arc flap, and at least one vent means adapted to enable emitting of the arc gases and/or particles from the electrical panel.

[0018] In one implementation, an apparatus for ventilating arc gases and/or particles, the apparatus comprises at least one arc flap adapted to provide a path to arc gases and/or particles from at least one electronic component, at least one arc deflector adapted to channelize, deflect and guide arc gases and/or particles received from the arc flap, a vent means adapted to enable emitting out internal arc gases and/or particles from the electronic component.

[0019] As compared to the conventional techniques, the present invention enables the hot gases and the particles generated due to thermal energy release are obstructed, deflected and guided in such a way that a delay is introduced in the release of hot gases and the particles, so thehot gases and the particles cool down in the confined space provided by the internal arc fault arrangement, to such an extent that they lose the momentum and is later vented out from the roof of the confined space. Thus the hot gases and the particles can no longer be harmful to the operating personal that might be in the near vicinity of the switchgear. Due to this technical advancement of the present invention the effective ability to withstand and absorb higher thermal along mechanical stress generated during internal arc fault is increased.Thus there is no need left to release the hot gas in the near vicinity (Outside of the substation/building) which will have other severe environmental factors. Also, the present invention enables to prohibit access to various parts/compartments.

[0020] Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The above and other aspects, features, and advantages of certain exemplary embodiments of the present invention will be more apparent from the following description taken in conjunction with the accompanying drawings in which:

[0021] Figure 1 illustrates a side view of an arrangement that includes a switchgear panel (01) with segregated compartments and an arc venting apparatus (02), in accordance with an embodiment of the present subject matter.

[0022] Figure 2 illustrates a side view of the panel with arc path from compartment, in accordance with an embodiment of the present subject matter.

[0023] Persons skilled in the art will appreciate that elements in the figures are illustrated for simplicity and clarity and may have not been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of various exemplary embodiments of the present disclosure.Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0024] The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary.

[0025] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.

[0026] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.

[0027] It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0028] By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[0029] Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in combination with or instead of the features of the other embodiments.

[0030] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

[0031] In one implementation, the electrical switchgear system comprises a switchgear panel (01) and an arc venting apparatus (02) wherein the switchgear panel is coupled with the arc venting apparatus using at least one of a technique selected from a group comprising bolting, welding or a combination thereof. It may be understood by the person skilled in the art that the present invention may use any of the known and/or new techniques for the coupling. However, any specific way / mechanisms of coupling are not mentioned in the present invention as it will create confusion to a reader and may divert from the scope of the present invention.

[0032] Referring now to figure 1, it discloses a side view of an arrangement that includes a switchgear panel (01) with segregated compartments and an arc venting apparatus (02), in accordance with an embodiment of the present subject matter. In one implementation the switchgear panel (01) is segregated into separate compartments. The arc venting apparatus may be formed of a metallic structure (02) that may include at least one arc flap (04), at least one arc deflectors (03) and at least one venting means (05). The venting means (05) may act as a diffuser to diffuse the arc partially or fully through its travel and later vent it outside the switchgear enclosure safely. It may be understood by the person skilled in that art that the mater used for the manufacturing of these component may include but not limited to the materials like sheet metal, stainless steel, etc., however it be any metal and shall not limit the protection scope of the present invention.

[0033] Referring now to figure 2, it discloses a side view of the panel with arc path from compartment, in accordance with an embodiment of the present subject matter. In one implementation, the arc path from compartment 1 is developed due to the internal arc fault in at least one of a segregated compartment of a switchgear system as shown in the figure 2. The arc gases and/or particles may be channelized in a direction using an internal arc guiding and deflecting components such as, arc flaps (04), arc deflectors (03) and venting means (05), which are together enclosed in a metallic structure. The arc may be partially or fully diffused along its elongated travel through the internal arc fault arrangement and ultimately vented out using the venting means safely from the roof of the electrical switchgear system.

[0034] In one implementation, the present invention provides a series of compartments or modules that are arranged in various configurations. Upon initiation of an arc fault within a particular (at least one) compartment, the arc flap (04) for that particular compartment will open, and the arc gases and/or particles are channeled into the arc venting apparatus, which flows through the arc venting chamber, and thereby guided and deflected by the arc deflector (03) to channelize through an exit path and safely out of the switchgear panel (01). In one example, the arc flap may be provided with each compartment. It may be loosely bolted or bolted with plastic bolts and operates/opens when high pressure is created in the compartment due to internal arc fault.

[0035] In one implementation, the arc/hot gases and the particles generated due to thermal energy release are obstructed, deflected and guided in such a way that a delay is introduced in the release of hot gases and the particles enabling it to cool down in the confined space of the switchgear panel provided by the internal arc fault arrangement, to such an extent that they lose the momentum and is later vented out from the roof of the switchgear panel. Hence, the arc/hot gases and the particles generated are longer harmful to the operating personal that might be in the near vicinity of the switchgear.

[0036] In one implementation, the vent means (05) may be a perforated sheet which is adapted to act as a diffuser to diffuse arc gases and/or particles partially and/or fully, and subsequently venting arc gases and/or particles out of the electrical enclosure.

[0037] In one implementation, the arc venting apparatus (02) operates in such a way that the pressure and/or hot arc gases produced within a compartment is controllably released from the top of the switchgear panel and prevented from entering into the other compartment in which an arc fault has not occurred.

[0038] In one implementation, the arc venting apparatus (02) may be a sheet metal structure having superior heat insulating qualities and is exceptionally strong and rigid in relation to its mass. The arc venting apparatus constitutes a self-contained structure which is furnished as a unit ready for production without any trimming or fitting in the field. It may be understood by the person skilled in that art that the mater used for the sheet metal of these component may include but not limited to the materials mild steel sheet, stainless steel sheet etc., however it be any metal and shall not limit the protection scope of the present invention. Further, the arc vent (02) is an assembly which is preassembled in factory and can be directly fitted on the panel at site. Thus it is a self-contained structure.

[0039] In one implementation, the electrical switchgear system is segregated into compartments which further consist of at least one of arc flap (04) for enabling arc gases and/or particles to flow therefrom to the arc venting apparatus.

[0040] In one implementation, the segregated compartments may have at least one arc flap (04) that are adapted to open upon occurrence of arc gases and/or particles.

[0041] In one implementation, the present invention provides an arrangement of switchgear/panel sheet metal type construction. The switchgear panel and an internal arc arrangement may be made of metal and may be held together or assembled in place with different methods like bolting, welding and the like. The switchgear in the present invention may be segregated into separate compartments as shown in figure 1. The present invention provides a sheet metal panel structure which has superior heat insulating qualities and which is exceptionally strong and rigid in relation to its mass. The present invention constitutes a self-contained structure assembly which is furnished as a unit ready for erection without any trimming or fitting in the field, thereby to promote speed and economical erection.

[0042] In one implementation, the internal arc fault guiding and deflecting arrangement of the present invention is designed with sheet metal structure, arc flaps, arc deflectors and perforated sheet which may acts as a diffuser, and may be positioned in such a way to diffuse the arc partially or fully through its travel and later vent it outside the switchgear panel safely as shown in figure 1.

[0043] In one implementation, as the arc path from compartment 1, developed due to the internal arc fault is shown in the figure 2. As shown in figure 2, the arc maybe channelized in the direction, with the help of a unique internal arc guiding and deflecting arrangement consisting of sheet metal structure, arc flaps, arc deflectors and perforated sheet.The arc may be partially or fully diffused along its elongated travel through the internal arc fault arrangement and ultimately vented out safely from the roof of the switchgear.

[0044] Some of the important features of the present invention, considered to be noteworthy are mentioned below:
1. Separate segregated compartment provide in a switchgear panel is designed in such a way to withstand severe stresses and cannot allow any damaging effect outside. This has the advantage, that the fault in the given compartment remains confined in the place of origin.
2. The arc venting apparatus withstands higher thermal and mechanical stress during internal arc fault.
3. The arc venting apparatus diffuses the arc fully or partially and then successfully carries away the hot gases and particles generated due to thermal energy release, away from the switchgear panel and the operating personal in the near vicinity of the switchgear to a desired location with no harm to the operator and no damage to the switchgear installation.
4. The present invention provides an ease in manufacturability of components and assembly in less time.
5. The present invention is optimized in terms of components used, resulting into cost effective as well as eco-friendly apparatus.
6. The present invention provides a rigid structure and light weight, resulting into ease of transportation and installation.
7. The present invention provides a flexible/adjustable arrangement for various variants offered.
8. The present invention provides a complete isolation and ingress protection to the electrical switchgear system.

[0045] It may be understood by the person skilled in that art that, the coupling, joining, fitting of the two components mentioned the present invention may be achieved by any of the existing coupling techniques that may include but not limited to nut and bolt arrangement, gluing, pasting, welding, and the like.

[0046] Although a system and apparatus for ventilation of arc gases/particles produced in an electrical switchgear system have been described in language specific to structural features and/or methods, it is to be understood that the embodiments disclosed in the above section are not necessarily limited to the specific features or methods or devices described. Rather, the specific features are disclosed as examples of implementations of the system and apparatus for ventilation of arc gases/particles produced in an electrical switchgear system
,CLAIMS:1. An electrical switchgear system having an electrical panel having at least one compartment for housing at least one electrical component CHARACTERIZED IN THAT comprising:
an arc venting apparatus for releasing arc gases and/or particles produced by an electrical arc fault in said compartment, wherein the internal arc venting apparatus comprises:
at least one arc flap adapted to provide a path to said arc gases and/or particles;
at least one arc deflectors adapted to channelize, deflect and guide said arc gases and/or particles received from said arc flap; and
at least one vent means adapted to enable emitting of said arc gases and/or particles from said electrical panel.

2. The electrical switchgear system as claimed in claim 1, wherein said switchgear panel is coupled with said arc venting apparatus by means of at least one technique selected from a group of techniques comprising bolting, welding, or a combination thereof.

3. The electrical switchgear system as claimed in claim 1, wherein said compartment consists of said arc flaps for enabling arc gases and/or particles to flow therefrom to said arc venting apparatus.

4. The electrical switchgear system as claimed in claim 1 and claim 2, wherein said arc flaps are adapted to open upon occurrence of arc gases and/or particles.

5. The electrical switchgear system as claimed in claim 1, wherein said vent means is a perforated sheet is adapted to work as a diffuser to diffuse arc gases and/or particles partially and/or fully, and subsequently venting it out of said electrical panel.

6. The electrical switchgear system as claimed in claim 1, wherein said internal arc venting apparatus is a sheet metal structure.

7. An arc venting apparatus for ventilating of arc gases and/or particles, the apparatus comprising:
at least one arc flap adapted to provide a path to arc gases and/or particles from at least one electronic component;
at least one arc deflector adapted to channelize, deflect and guide arc gases and/or particles received from said arc flap;
a vent means adapted to enable emitting out internal arc gases and/or particles from said electronic component.

8. The arc venting apparatus as claimed in claim 7, wherein said apparatus is a sheet metal structure positioned in an electrical system.

9. The arc venting apparatus as claimed in claim 7 wherein, said vent means is a perforated sheet and adapted to act as a diffuser and is positioned to diffuse said arc gases and/or particles partially and/or fully and subsequently venting it out of said electrical system.

10. The arc venting apparatus as claimed in claim 7, wherein said electrical system comprises at least one compartment that consists of said arc flaps that is adapted to open upon occurrence of arc gases and/or particles within said compartment and thereby enabling said arc gases and/or particles to flow there from to said internal arc venting apparatus.

11. An arc venting apparatus as claimed in claims 1-6 and claims 7-10 is characterized in that the hot gases and/or the particles generated due to thermal energy release in the electrical switchgear panel are obstructed, deflected and guided so as to introduce a delay in the release of the hot gases and/or the particles, which enables the hot gases and/or the particles to cool down in a confined space provided by the internal arc fault arrangement, to such an extent that they lose the momentum, and is then vented out from the roof of the confined space.