Disconnector contact system with controlled discharge

Abstract

Embodiments herein provide a disconnector (300) for an electrical device (200), comprising a first contact (310) having a longitudinal central axis and a second contact (320). At least one of the first contact (310) and the second contact (320) is movable in the direction of the longitudinal central axis of the first contact (310), and the first contact (310) is connected to the second contact (320) in the closed position and disconnected from the second contact (320) in the open position. The first contact (310) has a contact tip (330) at the end adjacent to the second contact (320) and facing the second contact (320). The contact tip (330) has an arcing tip (335) at the inner opening of the first contact (310) defined by the contact tip (330). The arcing tip (335) protrudes from the adjacent peripheral portion of the contact tip (330) in the direction of the longitudinal central axis.

Description

Technical Field

[0001] Technical Field The present disclosure generally relates to gas-insulated high-voltage equipment. More specifically, the present invention relates to a contact system of a switching device that controls the discharge starting point.

Background Art

[0002] Background Switching devices are used to insulate electrical equipment from power lines or to disconnect a portion of a power line from another portion. The switching device includes a disconnector switch DS (e.g., a vertical disconnector) and / or an earthing switch. The DS is a mechanical switch configured to connect or disconnect electrical equipment with respect to a power line. The DS is typically used in a high-voltage environment and forms a visible disconnection point to ensure reliable insulation of the electrical equipment from the power line so that the electrical equipment can operate or be maintained safely under no load. FIGS. 1 and 2 based on the published Cigre technical brochure are described herein. The DS100 has a contact system including two contacts, i.e., a movable contact 110 and a fixed contact 120 disposed in a sealed chamber, as shown in FIG. 1. In the normal state, the two contacts 110, 120 remain connected (i.e., in the closed position). When the DS is required to disconnect a part of the switching device, the two contacts 110 and 120 separate (i.e., in the open position), interrupting the electrical circuit.

[0003] Generally, in a disconnector 100 to which a working voltage is applied, a movable contact 110 is switched between a closed position and an open position during switching operations (e.g., bus charge switching current). Due to the action of the movable contact 110, a spark discharge or capacitive discharge (i.e., pre-strike or restrike discharge) may be formed between the two contacts 110 and 120 when switching the bus charge current. For example, during a closing operation, a spark may be formed before the movable contact 110 reaches / contacts the fixed contact 120. During an opening operation, a spark may be formed before the movable contact 110 reaches the fully open position. Furthermore, current continues to flow between the two contacts 110 and 120 through the spark. The enclosed compartment in which the two contacts 110 and 120 are located can contain a fluid insulating medium (either liquid or gas) to cool / extinguish the spark formed between the two contacts 110 and 120.

[0004] Furthermore, under certain conditions, the formed discharge / spark may cause a destructive discharge from the disconnector's contact system to the enclosure (i.e., ground potential), which can lead to internal sparking and failure of the disconnector. For example, a discharge / spark (i.e., pre-strike or restrike discharge) formed between contacts 110 and 120 of a partially closed contact system is shown in Figure 1, where the movable contact 110 is fixed in a specific position under multiple applied voltages.

[0005] In existing designs of the disconnector 100 contact system as described above, discharge / sparking can often begin at or near the leading edge (tip) of the movable contact 110, and the position of the movable contact 110 may be close to or on the outer surface of the tube of the movable contact 110. Therefore, such discharges are more likely to lead to destructive sparks / discharges into the enclosure compared to discharges / sparking that begin near the inner surface of the tube of the movable contact 110.

[0006] Furthermore, sparks / discharges formed between contacts 110 and 120 may damage elements of the disconnector 100 / CB by coming into contact with any other elements of the DS that may be at the sealed chamber or enclosure / ground potential. For example, how sparks propagate and establish contact with any other elements of the DS that may be at the sealed chamber or enclosure / ground potential is shown in Figures 2A, 2B, 2C, and 2D. [Overview of the project] [Problems that the invention aims to solve]

[0007] overview In existing designs of DS disconnectors, sparks may begin at or near the leading edge of the movable contact edge, close to or on the outer surface of the movable contact. Such sparks are more likely to come into contact with the sealed chamber of the DS or any other elements of the DS at ground potential compared to sparks that may begin closer to the inner surface of the movable contact or the longitudinal central axis.

[0008] The likelihood of such undesirable off-center discharges is greater at the moment the movable contacts are stressed with a positive potential during the busbar charging current switching task. In this configuration, the discharge origin can spread more widely across the movable contacts due to the lack of the first electron to initiate the discharge. For statistical reasons, discharges may occur at undesirable off-center locations.

[0009] In most cases, since neither of the two contacts of a disconnector is specially designed, sparks can originate from undesirable points on the movable contacts. Therefore, it is difficult to restrict the spark to remain at the axial center of the disconnector, and furthermore, it is difficult to avoid the spark coming into contact with any other elements of the disconnector that may be at the chamber or ground potential.

[0010] The problem of the absence of initial electrons to initiate discharge on a positively stressed movable contact can be overcome by supplying the initial electrons from the negatively stressed fixed contact side via field emission.

[0011] Therefore, a disconnector (DS) is needed in which at least one of the two contacts is designed in such a way that the spark is restricted to remain at the axial center of the disconnector, thereby preventing the spark from coming into contact with any other elements of the DS that may be at ground potential or in a sealed chamber.

[0012] Therefore, the object of this disclosure is to provide a disconnector for electrical equipment that mitigates, reduces, or eliminates all or at least some of the aforementioned shortcomings of solutions known at present. [Means for solving the problem]

[0013] This and other objectives are achieved by a disconnector as defined in the attached claims. The term "exemplary" should be understood in this context to mean an example, illustration, or representation.

[0014] According to one aspect of the present disclosure, a disconnector for an electrical device is provided. The disconnector comprises a first contact and a second contact having a longitudinal central axis, at least one of the first and second contacts being movable in the direction of the longitudinal central axis of the first contact, the first contact being connected to the second contact in a closed position, and the first contact being disconnected from the second contact in an open position, the first contact having a contact tip at an end adjacent to the second contact facing the second contact, the contact tip having an arcing tip provided in an inner opening of the first contact defined by the contact tip, the arcing tip projecting in the direction of the longitudinal central axis from an adjacent peripheral portion of the contact tip.

[0015] For field emission to occur, either the first or second contact point needs to have a suitable roughness. Ions generated by field emission can drift along the electric field lines to the other contact point, where they can separate electrons and initiate a spark / discharge.

[0016] Conveniently, in the proposed disconnector, the discharge / spark formed between the two contacts can occur closer to the longitudinal central axis of the first contact. As a result, the shielding effect of the fixed electrodes at the first and second contacts on the discharge path can be maximized.

[0017] Furthermore, the proposed disconnector reduces the risk of destructive discharge to the enclosure (i.e., ground potential) (i.e., pre-strike or restrike formed between the two contacts) when switching the bus charge current on and off. The risk of destructive discharge can be reduced by centering the discharge / spark path closer to the longitudinal central axis of the first contact.

[0018] According to some embodiments, the first contact is tubular. In some embodiments, the arcing tip is connected to the inner circumference of the end.

[0019]

number

[0020] It is positioned between and , where Ro is the outer radius of the contact tip at the end and Ri is the inner radius of the contact tip at the end.

[0021] In some embodiments, the angle between any two inner radii constituting the arc-starting tip is at least 90 degrees.

[0022] In some embodiments, the position of the arc-starting tip in the axial direction is equal to the vertex of the contour of the first contact point.

[0023] In some embodiments, the position of the arcing tip in the axial direction is above the apex of the contour of the first contact by the average radius of the arcing tip.

[0024] In some embodiments, in the open position, when a voltage difference is applied between the first contact and the second contact, the arcing tip has a greater electric field gradient compared to the remaining portion of the contact tip.

[0025] In some embodiments, in the open position, when a voltage difference is applied between the first contact and the second contact, the electric field gradient at the arcing tip is at least 20% greater compared to the remaining portion of the contact tip.

[0026] In some embodiments, in the open position, when a voltage difference is applied between the first contact and the second contact, the electric field gradient at the arcing tip is 30% to 70% greater compared to the remaining portion of the contact tip.

[0027] In some embodiments, the circuit breaker includes a spindle extending through the first contact, the spindle having a longitudinal central axis that coincides with the longitudinal central axis of the first contact, and the contact tip defines an opening provided for the protrusion of the spindle with respect to the movement of the spindle relative to the first contact in the direction of the longitudinal central axis of the first contact.

[0028] In some embodiments, the second contact presents a recess in which the arcing tip is received without physically contacting the second contact in the closed position of the circuit breaker.

[0029] In some embodiments, the contact tip of the first contact is rotationally symmetric, and the diameter of the rotation is at least larger than the average radius of the arcing tip.

[0030] In some embodiments, the first contact is movably arranged in the direction of the longitudinal central axis, the second contact is a fixed contact, and in the closed position, the contact tip is connected to the second contact.

[0031] In some embodiments, the thickness of the wall of the first contact point is greater than at least the average radius of the arcing tip, and the average radius of the arcing tip is less than at least the average radius of the surrounding portion of the contact point tip, if the first contact point is rotationally symmetric.

[0032] In some embodiments, the average radius of the ignition tip is at least a threshold number smaller than the average radius of the surrounding portion of the contact tip, where the threshold is 5+5 times the surface ratio, and the surface ratio is the ratio of the rest of the first contact to the ignition tip.

[0033] In some embodiments, the disconnector includes an insulating medium between a first contact (310) and a second contact (320), the insulating medium comprising at least one of sulfur hexafluoride (SF6), air, carbon dioxide (CO2), oxygen (O2), a fluoroketone mixture, and a nitrile mixture.

[0034] Conveniently, the proposed arrangement of the first and second contacts, as well as the special design of the electrode shape of the first contact, allows the discharge / spark to be generated from a predetermined contact area. This centers the discharge / spark path by moving it closer to the longitudinal central axis of the first contact.

[0035] Other advantages may be readily apparent to those skilled in the art. Certain embodiments may have some or all of the listed advantages.

[0036] Brief explanation of the drawing The above will become clear from the following more specific description of the exemplary embodiments shown in the attached drawings. In the attached drawings, similar reference numerals throughout the various figures refer to the same parts. The drawings are not necessarily to scale, but rather the emphasis is on illustrating exemplary embodiments. [Brief explanation of the drawing]

[0037] [Figure 1]A schematic diagram of an exemplary disconnector based on prior art is shown (based on Cigre Brochure 260). [Figure 2] a) to d) disclose exemplary paths that a prior art spark may take to establish contact with any other element of a disconnector switch DS at a sealed chamber or enclosure / ground potential (Figure based on Cigre brochure 260). [Figure 3] Schematic diagrams illustrating exemplary disconnectors according to several embodiments are disclosed. [Figure 4] Schematic diagrams illustrating exemplary movable contacts according to several embodiments are disclosed. [Figure 5] A schematic diagram showing an example of the radius of a movable contact is disclosed. [Figure 6A] A schematic diagram showing an example of the arcing tip of a movable contact is disclosed. [Figure 6B] A schematic diagram showing an example of the arcing tip of a movable contact is disclosed. [Figure 6C] A schematic diagram showing an example of the arcing tip of a movable contact is disclosed. [Figure 6D] A schematic diagram showing an example of the arcing tip of a movable contact is disclosed. [Figure 7] Schematic diagrams illustrating exemplary fixed contacts according to several embodiments are disclosed. [Modes for carrying out the invention]

[0038] Detailed explanation Aspects of this disclosure are described more fully below with reference to the accompanying drawings. However, the disconnectors disclosed herein can be realized in many different forms and should not be construed as being limited to the embodiments described herein. Similar numbers in the figures refer to similar elements throughout.

[0039] The terms used herein are solely for the purpose of describing specific aspects of this disclosure and are not intended to limit the invention. It should be emphasized that, as used herein, the terms “equipped with / equipped with” specify the presence of the feature, element, step, or component described herein, but do not preclude the presence or addition of one or more other features, elements, steps, components, and / or groups thereof. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural form unless the context makes it clear otherwise.

[0040] Figure 3 discloses a schematic diagram of an exemplary disconnector 300 for an electrical device 350. The electrical device 350 may be a disconnector switch DS. The DS may be a switching device capable of connecting, leading, and disconnecting current in an electrical circuit under normal circumstances. The DS may be configured to connect and lead current in an electrical circuit for a specific period of time under specific abnormal circumstances and then automatically disconnect it. In one example, the specific abnormal circumstances may be a short-circuit fault.

[0041] The disconnector 300 referred to herein may be configured in conjunction with an electrical device 200. The disconnector 300 may be a gas-insulated switchgear (GIS) disconnector, or a combination of components of an air-insulated switchgear (AIS), or a mixed-technology switchgear (MTS) which is a combination of an AIS and a GIS disconnector. The disconnector 300 comprises a contact system having at least two contacts, namely a first contact 310 and a second contact 320. At least one of the two contacts, namely the first contact 310 or the second contact 320, may be tubular in shape, and the tubular shape may be elongated, circular, and hollow like a pipe. In one example, as shown in Figure 3, the first contact 310 is tubular in shape. Of the two contacts, at least one contact configured to move, for example the first contact 310, may be a movable contact MC, and the other contact of the two contacts, for example the second contact 320, may be a fixed contact FC. Accordingly, in some embodiments described herein, the terms first contact, movable contact, and MC are used interchangeably. Similarly, the terms second contact and FC are used interchangeably.

[0042] The two contacts 310 and 320 are electrical conductors and can be at potential while the DS is operating. The first contact 310 and the second contact 320 may be located within a sealed chamber. The sealed chamber can contain a fluid insulating medium (either liquid or gas).

[0043] During switching operations (e.g., busbar charging switching current), the first contact 310 is switched between a closed position and an open position. The switching of the first contact 310 may cause a spark or discharge (i.e., a pre-strike or restrike discharge) to form between the first contact 310 and the second contact 320. A fluid insulating medium in a sealed chamber cools / extinguishes the spark. The insulating medium in the DS on which the circuit interruption is performed may be, but is not limited to, one or more of the following: oil, air break, air blast, sulfur hexafluoride (SF6), eco-gas (air, CO2, O2, etc.), vacuum, fluoroketone mixture, nitrile mixture, etc.

[0044] More specifically, when the first contact 310 of the two contacts begins to move / separate from the second contact 320, the insulating medium between the two contacts 310 and 320 is subjected to significantly large electrical stress. The electrical stress can be approximately inversely proportional to the distance between the first and second contacts 310 and 320. At the moment of separation of the first and second contacts 310 and 320, the insulating medium between the first and second contacts 310 and 320 may undergo dielectric breakdown due to the large electrical stress. Dielectric breakdown of the insulating medium can result in the formation of a conductive path or spark between the first and second contacts 310 and 320. As the first contact 310 moves further away from the second contact 320, the spark is stretched along with the movement of the first contact 310. Current interruption is not achieved because current continues to flow between the first and second contacts 310 and 320 through the spark. It can be argued that the interruption of the current is only achieved when the spark eventually cools down / extinguishes and ceases to exist.

[0045] In most cases, since the first and second contacts 310 and 320 of the disconnector 300 are not specially designed, sparks can originate from any point on the first contact 310, i.e., from an undesirable point on the first contact 310. Such sparks / discharges are more likely to lead to destructive sparks into the enclosure (i.e., ground potential). Furthermore, it can be difficult to restrict sparks to remain near the center of the first contact 310, i.e., the longitudinal central axis. Thus, it can be difficult to avoid sparks coming into contact with other elements of the DS that may be at ground potential / enclosure, leading to internal sparks and failures in the CB. The longitudinal central axis is a hypothetical line passing through the centroid of a cross-section along the long axis of any object.

[0046] Accordingly, embodiments of the present disclosure provide a disconnector 300 for an electrical device 200, which is designed to concentrate a spark toward the longitudinal central axis of a first contact 310.

[0047] As shown in Figure 3, the disconnector 300 comprises a first contact 310 and a second contact 320. The first contact 310 is cylindrical in shape with a longitudinal central axis. The first contact 310 may be movably positioned in the direction of the longitudinal central axis, and the second contact 320 may be a fixed contact. The first contact 310 is connected to the second contact 320 in the closed position. The first contact 310 is disconnected from the second contact 320 in the open position. The first contact 310 may have an end face facing the second contact 320. The first contact 310 and the second contact 320 may be housed in a sealed chamber. In some examples, the sealed chamber may contain an environmentally friendly gas mixture such as air, CO2, O2, a fluoroketone mixture, or a nitrile mixture as an insulating medium.

[0048] In some embodiments, the disconnector 300 includes a dielectric shield 340 surrounding the first contact 310.

[0049] At least one of the first contact 310 and the second contact 320 is movable in a direction along the longitudinal central axis of the first contact 310. In one example, the longitudinal central axis of the first contact 310 is the same as the longitudinal central axis of the disconnector 300. The longitudinal central axis is an imaginary line passing through the centroid of the cross-section along the major axis of any object.

[0050] Furthermore, at least one of the pairs of first and second contacts 310 and 320 of the disconnector 300 faces the other contact of the pair and has a contact tip 330 at one end adjacent to the other contact of the pair. In one example, the first contact 310 faces the second contact 320 and has a contact tip 330 at one end of the first contact adjacent to the second contact 320.

[0051] Figure 4 discloses a schematic diagram of an exemplary first contact 310 of a disconnector 300. In one example, the first contact 310 of the disconnector 300 faces the second contact 320 of the disconnector 300 and has a contact tip 330 at one end adjacent to the second contact 320 of the disconnector 300. The contact tip 330 has arcing tips 335, 335a, and 335b provided in the inner opening of the first contact 310 defined by the contact tip 330. The arcing tip 335 projects in the direction of the longitudinal central axis from the adjacent peripheral portion of the contact tip. The arcing tip 335 is closer to the second contact 320 than the other remaining / adjacent portions of the contact tip 330. The adjacent portions may be the remaining portions of the contact tip 330 other than the arcing tip 335. The arc-generating tip 335 may be positioned closer to the longitudinal central axis of the first contact point 310 than the adjacent portion. In one example, the arc-generating tip 335 is positioned closer to the inner circumference of the end and

[0052]

number

[0053] The contact tip 330 is positioned between the two, where Ro is the outer radius of the contact tip 330 at the end and Ri is the inner radius of the contact tip 330 at the end. The contact tip 330 connects to the second contact 320 in the closed position. In one example, the angle between any of the two radii constituting the arcing tip 335 is at least 90 degrees.

[0054] In one example, the arc-starting tip 335 is positioned at a point in the axial direction that is geometrically equivalent to the vertices of contours 360, 360a, and 360b of the first contact point 310. In another example, the position of the arc-starting tip 335 at a point in the axial direction is greater than or equal to the vertex of contour 360 of the first contact point 310, according to the average radius of the arc-starting tip 335. In particular, the projection of the arc-starting tip in the axial direction is to a point that is geometrically equivalent to the vertex of contour 360, or greater than or equal to the vertex of contour 360, according to the average radius of the arc-starting tip 335.

[0055] When a voltage difference is applied between the first and second contacts in the open position, the firing tip 335 has a larger electric field gradient compared to the rest of the contact tip 330. In some examples, when a voltage difference is applied between the first and second contacts 320 in the open position, the electric field gradient at the firing tip 335 is at least 20% greater than that of the rest of the contact tip 330. In another example, when a voltage difference is applied between the first and second contacts in the open position, the electric field gradient at the firing tip 335 is 30% to 70% greater than that of the rest of the contact tip 330.

[0056] Conveniently, by limiting the arcing tip 335 to a specific position closer to the longitudinal central axis, the risk of a positive polarity central spark / discharge is reduced.

[0057] The disconnector 300 comprises a spindle 370 that extends through the first contact 310 and has a longitudinal axis that coincides with the longitudinal axis of the first contact 310. The contact tip 330 defines an opening provided for the protrusion of the spindle in relation to the motion of the spindle relative to the first contact 310 in the direction of the longitudinal axis of the first contact 310.

[0058] The disconnector 300 includes dielectric shields 340, 340a, and 340b surrounding the first contact 310. The dielectric shields 340 extend to the region of the contact tip 330 and are in physical contact with the contact tip 330 within that region. The contact tip 330 of the first contact 310 is the end face facing the second contact 320. The contact tip 330 partially closes the opening of the dielectric shield 340 so as to leave sufficient space between the dielectric shield 340 and the first contact 310 for the movement of the first contact 310 on the spindle 370. The dielectric shields 340 extend to the end region of the first contact 310 adjacent to the second contact 320. Conveniently, the present invention prevents deterioration of the dielectric shield by directing the spark to the center (inner circumference) of the first contact rather than the outer circumference of the first contact.

[0059] Figure 5 discloses an alternative embodiment in which a projection of the firing tip 335 is disclosed. The projection protrudes from the peripheral portion, i.e., the outer edge, of the contact tip 330 in the longitudinal central axis direction. The projection is defined by R1 and R6, as shown in Figure 5.

[0060] Figure 6A discloses multiple radii rsi at different points on the arc tip 335. The arithmetic mean radius is rs. The angle between any two of the multiple radii constituting the arc tip 335 is at least 90 degrees. Figure 6B discloses the position of the arc tip 335 in the axial direction, which is equal to the vertex of the contour 360 of the first contact point 310. In another example, the position of the arc tip 335 in the axial direction is greater than or equal to the vertex of the contour 360 of the first contact point 310 by the average radius of the arc tip 335. In particular, the difference between the position of the arc tip 335 and the point of the contour vertex may be at most equal to the average radius. Figure 6C discloses the diameter of rotation of the first contact point 310 in an example where the first contact point 310 is rotationally symmetric. The diameter of rotation is greater than the average radius of the arc tip 335. In one example, the diameter of the rotation is at least 5 times larger than the average radius of the arcing tip 335. In another example, the average radius of the arcing tip 335 is smaller than the average radius of the surrounding portion of the contact tip 330. In yet another example, the average radius of the arcing tip 335 is at least 5 times smaller than the average radius of the surrounding portion of the contact tip 330. Figure 6D discloses an average radius of the arcing tip 335 that is at least a threshold number of times smaller than the average radius of the surrounding portion of the contact tip 330. In one example, the threshold is 5+5 times the surface ratio, where the surface ratio is the ratio of the rest of the first contact 310 to the arcing tip 335.

[0061] Figure 7 discloses a schematic diagram of the second contact 320. Dielectric shields 308a and 308b surround the second contact 320. The second contact 320 has a recess 304 into which the arcing tip 335 is received without physical contact with the second contact 320 when the disconnector 300 is in the closed position. The second contact 320 is designed so that the second contact 320 avoids physical contact with the arcing tip 335 when it is in the closed position. The second contact 320 is designed to include a recess 304 and a groove 302 on its end face 306. The recess 304 is configured to accommodate the arcing tip 335 in the closed position so as to avoid physical contact between the arcing tip 335 and the second contact 320 when it is in the closed position. The groove 302 is configured to accommodate the remaining portion of the contact tip 330.

[0062] For a spark / discharge to be established, an initial electron is needed to initiate an electron avalanche. As the first contact 310 moves, a spark or pre-strike and restrike discharge is initiated from the ignition tip 335, which is close to the inner surface of the first contact 310, as shown in Figure 4. When a voltage difference is applied between the first contact 310 and the second contact 320, in the open position, the ignition tip 335 has a larger electric field gradient compared to the rest of the contact tip 330, and therefore causes a discharge from the ignition tip 335.

[0063] Therefore, by inducing a discharge to begin at the ignition tip 335 near the longitudinal central axis of the first contact 310, the spark / discharge occurring between at least two contacts 310 and 320 can be centered toward the longitudinal central axis. Conveniently, the risk of spark diffusion is minimized, and thus the risk of DS failure is eliminated.

[0064] The above description of specific embodiments fully illustrates the general nature of the embodiments herein, and it should be understood, and is intended, that others, by applying their current knowledge, can easily modify and / or adapt such specific embodiments to various uses without departing from the overall concept, and that such adaptations and modifications are therefore included in the meaning and scope of the equivalents of the disclosed embodiments. It should be understood that any expressions or terms used herein are for illustrative purposes only and not for limitation. Thus, although the embodiments herein have been described in relation to preferred embodiments, those skilled in the art will recognize that the embodiments herein can be carried out with modifications within the scope of this disclosure.

Claims

1. A circuit breaker (300) for an electrical device, A first contact point (310) having a longitudinal central axis, and Second point of contact (320) It is equipped with, At least one of the first contact (310) and the second contact (320) is movable in the direction of the longitudinal central axis of the first contact (310), the first contact (310) is connected to the second contact (320) in the closed position, the first contact (310) is disconnected from the second contact (320) in the open position, and the first contact (310) faces the second contact (320). A disconnector (300) having a contact tip (330) at an end adjacent to a second contact (320), the contact tip (330) comprising arcing tips (335a, 335b) provided in the inner opening of the first contact (310) defined by the contact tip (330), the arcing tips (335a, 335b) protruding from the adjacent peripheral portion of the contact tip (330) in the direction of the longitudinal central axis.

2. The disconnector (300) according to claim 1, wherein the arcing tip portions (335a, 335b) are located between the inner circumference of the end and Ri + 1 / 3 (Ro - Ri), where Ro is the outer radius of the contact tip portion (330) at the end and Ri is the inner radius of the contact tip portion (330) at the end.

3. The disconnector (300) according to any of the preceding claims, wherein the angle (θ) between any two inner radii (600a) of the contact tip (330) at the end that constitutes the arcing tip (335a, 335b) located between the inner circumference of the end and Ri + 1 / 3 (Ro - Ri) is at least 90 degrees.

4. The disconnector (300) according to any one of claims 1 to 3, wherein the position of the arc-starting tip portions (335a, 335b) in the axial direction is to a point geometrically equal to the vertex of the contour (360a, 360b) of the first contact (310) based on the average radius of the arc-starting tip portions (335a, 335b) located between the inner circumference of the end and Ri + 1 / 3 (Ro - Ri).

5. In the open position, when a voltage difference is applied between the first contact and the second contact, the arcing tip portions (335a, 335b) have a larger electric field gradient than the rest of the contact tip portion (330), as described in any of the preceding claims, the disconnector (300).

6. In the open position, when a voltage difference is applied between the first contact and the second contact, the electric field gradient at the firing tip portions (335a, 335b) is at least 20% greater than that of the rest of the contact tip portion (330), the disconnector (300) according to any of the preceding claims.

7. In the open position, when a voltage difference is applied between the first contact and the second contact, the electric field gradient at the firing tip portions (335a, 335b) is 30% to 70% greater than that of the rest of the contact tip portion (330), the disconnector (300) according to any one of claims 1 to 4.

8. A spindle (370) extending through the first contact (310) and having a longitudinal central axis that coincides with the longitudinal central axis of the first contact (310). Equipped with, The disconnector (300) according to any of the preceding claims, wherein the inner opening defined by the contact tip (330) is provided for the protrusion of the spindle with respect to the movement of the spindle relative to the first contact (310) in the direction of the longitudinal central axis of the first contact (310).

9. The disconnector (300) according to any of the preceding claims, wherein the second contact (320) exhibits a recess (304) into which the arcing tip portions (335a, 335b) are received without physically contacting the second contact (320) when the disconnector (300) is in the closed position.

10. The disconnector (300) according to any of the preceding claims, wherein the contact tip (330) of the first contact (310) is rotationally symmetric, and the diameter of the rotation is greater than the average radius of the arcing tip (335) located at least between the inner circumference of the end and Ri + 1 / 3 (Ro - Ri).

11. The disconnector (300) according to any of the preceding claims, wherein the first contact (310) is movably arranged in the direction of the longitudinal central axis, and the second contact (320) is a fixed contact, and in the closed position, the contact tip (330) is connected to the second contact (320).

12. The disconnector (300) according to any of the preceding claims, wherein the wall thickness of the first contact (310) is greater than the average radius of the ignition tip portions (335a, 335b) located between the inner circumference of the end and Ri + 1 / 3 (Ro - Ri), and the average radius of the ignition tip portions (335a, 335b) is less than the average radius of the surrounding portion of the contact tip portion (330).

13. The disconnector (300) according to any of the preceding claims, wherein the average radius of the firing tip portions (335a, 335b) located between the inner circumference of the end and Ri + 1 / 3 (Ro - Ri) is at least a threshold number smaller than the average radius of the surrounding portion of the contact tip portion (330) in the direction of the longitudinal central axis, the threshold being 5 + 5 times the surface ratio, and the surface ratio being the ratio of the remaining portion of the first contact (310) to the firing tip portions (335a, 335b).

14. It is provided with an insulating medium between the first contact (310) and the second contact (320), The disconnector (300) according to any of the preceding claims, wherein the insulating medium comprises at least one of sulfur hexafluoride (SF6), air, carbon dioxide (CO2), oxygen (O2), a fluoroketone mixture, and a nitrile mixture.

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