WO2017125333A1

WO2017125333A1 - High-voltage switching device having a particle trap, and method for trapping particles in a high-voltage switching device

Info

Publication number: WO2017125333A1
Application number: PCT/EP2017/050755
Authority: WO
Inventors: Michiel TAVERNIER; Ulrich Straumann
Original assignee: ABB Schweiz AG
Current assignee: ABB Schweiz AG
Priority date: 2016-01-20
Filing date: 2017-01-16
Publication date: 2017-07-27
Anticipated expiration: 2018-07-20

Abstract

A high-voltage gas-insulated switchgear device (100) having a metallic encapsulation (110) including a particle trap (120) for holding particles is described. The particle trap (120) includes a cavity (130) in the encapsulation (110) and a shield arrangement (140). The shield arrangement (140) is at least partially arranged within the cavity (130), wherein the shield arrangement (140) includes a plurality of guiding elements (150) for guiding particles into the cavity (130), and wherein two or more adjacent guiding elements of the plurality of guiding elements (150) provide a particle guiding passage (155) to the bottom (131) of the cavity (130) of the particle trap (120). The plurality of guiding elements (150) of the shield arrangement is connected to each other for providing a shield arrangement insert. At least a portion of the two or more adjacent guiding elements of the plurality of guiding elements (150) are configured for providing an at least partially inclined particle guiding passage (155) with respect to a horizontal at a bottom (131) of the cavity (130) of the particle trap (120).

Description

HIGH-VOLTAGE SWITCHING DEVICE HAVING A PARTICLE TRAP, AND METHOD FOR TRAPPING PARTICLES IN A HIGH-VOLTAGE SWITCHING DEVICE

TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to the field of gas-insulated metal- enclosed high-voltage switchgear technology. In particular, embodiments of the present disclosure relates to high- voltage gas-insulated metal-enclosed switching devices, particularly circuit breakers, having a particle trap. Further, embodiments of the present disclosure relate to a method for separating particles, in particular conductive particles, in a high- voltage gas- insulated metal-enclosed switchgear device, particularly a circuit breaker.

BACKGROUND [0002] It has been found that particles which are located within the encapsulation housing of a high-voltage switching device can reduce the dielectric strength of the high-voltage switching device. Therefore, in order to reduce the negative effects of particles within a high- voltage switchgear device, particle traps for collecting particles have been implemented. In particular, particle traps are often used in high-voltage switching devices which have a grounded, metallic encapsulation housing enclosing movable switching elements. Accordingly, particles which are inside the encapsulation housing of a high-voltage switching device, which may, for example, be generated during switching, can be separated and collected inside the particle trap. Ideally, the particles remain within the particle trap, such that a high- voltage switching device having a sufficiently high dielectric strength which is not reduced by these particles can be provided.

[0003] Conventionally, particle traps are provided within high- voltage switching devices, e.g. circuit breakers, by adding slot cavities to the encapsulation housing or by mounting electrodes to form regions with low electric field. The location and orientation of the particle traps are usually chosen based on particle collection results after testing. Ideally, the dimensioning of the slot cavities forming the particle traps is done in such a way that a lift-off of the particles from the slot cavities can be avoided. Exemplary representatives of prior art particle traps are disclosed in EP1761983A1; JP2009268294A2; US4085807A; JP-H05- 15607 U.

[0004] However, it has been found that the trapping efficiency of the conventional particle traps is quite low, particularly for particles having high kinetic energy. Further, it has been found that particles collected in the conventional particle traps can be pushed out from the particle trap by gas flows occurring inside the switching device, which may for example be caused by the movement of the switching elements during switching. Hence, such conventional high- voltage switching devices have the disadvantage that its operational reliability are not ensured well during operation. [0005] In view of the above, it is an object of embodiments described herein to provide a high-voltage switching device having a particle trap with an improved particle retention characteristic in order to improve the operational reliability of the high- voltage switching device.

SUMMARY [0006] In view of the above, a high- voltage switchgear device having a metallic encapsulation including a particle trap for holding particles and a method for separating particles in a high- voltage switchgear device according to the independent claims are provided. Further advantages, features, aspects and details are apparent from the dependent claims, the description and drawings. [0007] According to one aspect of the present disclosure, a high-voltage switching device having a metallic encapsulation including a particle trap for holding particles is provided. The particle trap includes a cavity in the encapsulation and a shield arrangement. The shield arrangement is at least partially arranged within the cavity, wherein the shield arrangement includes a plurality of guiding elements for guiding particles into the cavity, and wherein two or more adjacent guiding elements of the plurality of guiding elements provide a particle guiding passage to the bottom of the cavity of the particle trap.

[0008] According to another aspect of the present disclosure, a method for separating particles in a high- voltage gas-insulated metal-enclosed switchgear device is provided. The method includes guiding particles to a bottom of a cavity of a particle trap provided in a metallic encapsulation of the high- voltage switching device, wherein guiding is conducted by two or more adjacent guiding elements of a plurality of guiding elements of a shield arrangement which is at least partially arranged within the cavity. Further, the method includes employing the shield arrangement for hindering the particles guided into the particle trap from escaping the particle trap, wherein the shield arrangement includes a plurality of guiding elements for guiding particles into the cavity, and wherein two or more adjacent guiding elements of the plurality of guiding elements provide a particle guiding passage to the bottom of the cavity of the particle trap.

[0009] It is to be understood that embodiments of the particle trap having guiding elements as described herein are configured to guide particles, e.g. particles falling from a gas nozzle area of a gas insulated switch gear device or particles falling from an insulation area of a disconnector, to the bottom of the particle trap. Additionally, it is to be noted that the guiding elements of the particle trap as described herein are configured and arranged such that the particles collected at the bottom of the particle trap are prevented from leaving the particle trap. Accordingly, trapped particles are prevented from leaving the particle trap, for example towards a gas nozzle area of a gas insulated switch gear device or an insulation area of a disconnector. According to a further aspect of the present disclosure, an existing high- voltage switching device having an encapsulation including a cavity for particle trapping may be retrofitted with a shield arrangement according to embodiments described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, is provided by reference to embodiments. The accompanying drawings relate to embodiments of the disclosure and are described in the following: [0011] Fig. 1 shows a schematic sectional view of a high- voltage gas-insulated metal enclosed switching device according to embodiments described herein;

[0012] Fig. 2 shows an enlarged view of a particle trap of a high- voltage gas-insulated metal enclosed switchgear device according to embodiments described herein; [0013] Fig. 3 shows a cross-sectional view along the line A-A of the enlarged view of the particle trap as shown in Fig. 2;

[0014] Figs. 4A and 4B shows a schematic top views of a particle trap of a high-voltage gas-insulated metal enclosed switchgear device according to embodiments described herein; [0015] Fig. 5 shows an enlarged view of a particle trap of a high- voltage gas-insulated metal enclosed switchgear device according to further embodiments described herein;

[0016] Fig. 6 shows an enlarged view of a particle trap of a high- voltage gas-insulated metal enclosed switchgear device according to yet further embodiments described herein;

[0017] Fig.7 shows an enlarged view of a particle trap of a high- voltage gas-insulated metal enclosed switchgear device according to yet further embodiments described herein; and

[0018] Figs. 8 A and 8B show schematic block diagrams illustrating a method for separating particles in a high- voltage switchgear device according to embodiments described herein.

DETAILED DESCRIPTION OF EMBODIMENTS [0019] Reference will now be made in detail to the various embodiments of the disclosure, one or more examples of which are illustrated in the figures. Within the following description of the drawings, the same reference numbers refer to same components. In the following, only the differences with respect to individual embodiments are described. Each example is provided by way of explanation of the disclosure and is not meant as a limitation of the disclosure. Further, features illustrated or described as part of one embodiment can be used on or in conjunction with other embodiments to yield yet a further embodiment. It is intended that the description includes such modifications and variations.

[0020] In the present disclosure, the term "high-voltage gas-insulated switchgear device" shall encompass devices like circuit breakers, disconnectors and other switch devices, such as earthing switches, e.g. fast acting earthing switches, as well as all elements of a switchgear in general (also elements without mechanical operated contacts). [0021] In the present disclosure, the term "high voltage" is to be understood to denote a voltage above about 1 kV, in particular above about 50kV, more particularly above about 145 kV.

[0022] In the present disclosure, the term "particle trap" may be apprehended as a trap for collecting particles. In particular, a particle trap as described herein may be understood as a particle trap arranged within a high- voltage gas-insulated metal enclosed switchgear device, particularly a circuit breaker.

[0023] In the present disclosure, the term "shield arrangement" may be understood as an arrangement having two or more shield elements, e.g. guiding elements as described herein. In particular, a shield arrangement may be understood as an arrangement of connected shield elements such that the shield arrangement can be provided as one structural unit, particularly in form of a one piece structure. For example, the shield elements, e.g. the guiding elements as described herein, may be in the form of plates or sheets.

[0024] In the present disclosure, the term "guiding element" may be understood as an element of a shield arrangement as described herein. In particular, a guiding element as described herein may have at least one continuous surface which is configured for directing impinging particles to a bottom of a particle trap. More particularly, guiding elements as described herein have the functionality to reflect particles entering the particle trap deeper inside the particle trap. Thereby, incoming particles may typically experience many particle reflections between adjacent guiding elements such that the particles lose much of their initial kinetic energy. Further, a large part of translational kinetic energy of the particles can be converted to rotational energy by the reflections between adjacent guiding elements.

[0025] In the present disclosure, the term "particle guiding passage" may be understood as a passage in between two adjacent guiding elements of a shield arrangement as described herein. In particular, a particle guiding passage as described herein may be configured for guiding particles impinging on at least one of two adjacent guiding elements towards the bottom of a particle trap as described herein.

[0026] In Fig. 1 shows a schematic sectional view of a high-voltage gas-insulated metal enclosed switchgear device 100, particularly a gas-insulated metal enclosed circuit breaker, according to embodiments described herein. As exemplarily shown in Fig. 1, the high- voltage switchgear device 100 has an encapsulation housing 110 including a particle trap 120 for holding particles. The particle trap 120 includes a cavity 130 in the encapsulation housing 110 and a shield arrangement 140. The shield arrangement 140 is at least partially arranged within the cavity 130. Further, the shield arrangement 140 includes a plurality of guiding elements 150 for guiding particles into the cavity 130. According to embodiments described herein, two or more adjacent guiding elements of the plurality of guiding elements 150 are arranged for providing a particle guiding passage 155 to the bottom 131 of the cavity 130 of the particle trap 120, as shown in more detail in Figs. 2 to 7. As exemplarily shown in Fig. 1, the particle traps 120 may be located at the bottom of the encapsulation housing 110. Accordingly, a faster trapping time can be achieved and the risk of particles being restricted to a certain area due to the electrostatic forces can be reduced.

[0027] Fig. 2 shows an enlarged view of a particle trap 120 of a high-voltage switching device 100 according to embodiments described herein. As exemplarily shown in Fig. 2, at least a portion of the two or more adjacent guiding elements of the plurality of guiding elements 150 is configured for providing an at least partially inclined particle guiding passage 155 to the bottom 131 of the cavity 130 of the particle trap 120. The particle guiding passage 155 is exemplarily indicated as dotted arrow in Fig. 2. Further, the two or more adjacent guiding elements of the plurality of guiding elements may include at least a guiding surface which is parallel to a guiding surface of an adjacent guiding element. Particularly, as shown in Fig. 2, adjacent guiding surfaces of two or more adjacent guiding elements of the plurality of guiding elements may be parallel to each other. Accordingly, particles impinging on at least one of the two or more adjacent guiding elements of the shield arrangement can be guided to the bottom of the particle trap such that the particle lose their kinetic energy on their way to the bottom of the particle trap. Typically, the bottom of the particle trap is a low electric field region. Further, as can be seen form the exemplary embodiment shown in Fig. 2, according to embodiments described herein, the shield arrangement is configured for hindering particles to leave the particle trap once the particles have been guided to the bottom of the particle trap. Thus, the particle trapping efficiency can be increased.

[0028] According to embodiments which can be combined with any other embodiments described herein, the at least partially inclined particle guiding passage 150 is inclined with respect to a horizontal at the bottom 131 of the cavity 130 of the particle trap 120 by an inclination angle (alpha) from 20° to 160°, particularly by an angle (alpha) from 30° to 150°. For example, the inclination angle (alpha) may be selected from a range between a lower limit of alpha=20°, particularly a lower limit of alpha=30°, more particularly a lower limit of alpha=40°, to an upper limit of alpha= 140°, particularly to an upper limit of alpha= 150, more particularly to an upper limit of alpha= 160. [0029] Although, the bottom 131 of the cavity 130 of the particle trap 120 as exemplarily shown in Fig. 2 is flat, it is to be understood that the bottom of the particle trap may have a bowl shaped cross section, a wave-form cross section or a ribbed profile, e.g. as illustrated in Fig. 7. Accordingly, it is to be understood that the horizontal at the bottom 131 of the cavity 130 of the particle trap 120 for defining the inclination angle (alpha) is independent form the cross-sectional shape or the topology of the bottom of the cavity.

[0030] With exemplarily reference to Figs. 1 and 2, it is to be understood that typically the horizontal at the bottom 131 of the cavity 130 of the particle trap 120 for defining the inclination angle (alpha) is parallel to a switching axis 111 of the switchgear device 100 as described herein. Accordingly, it is to be understood that the inclination angles (alpha, alpha- 1 and alpha-2) may also be defined with respect to the switching axis 111.

[0031] With exemplarily reference to Fig. 2, according to embodiments which can be combined with other embodiments described herein, the outer edge 132 of the cavity 130 of the particle trap 120 may include a slope with a slope angle (beta) from beta=l° to beta=4° with respect to a horizontal. In particular, the slope angle (beta) may be beta=2°. Thereby, the particle trapping efficiency of the particle trap can be increased since particles arriving at the particle trap with a small impinging angle can be trapped more efficiently.

[0032] With exemplarily reference to Fig. 2, according to embodiments which can be combined with any other embodiments described herein, the distance D between two adjacent guiding elements of the plurality of guiding elements is from 5 mm to 20 mm. For example, the distance D may be selected from a range between a lower limit of D=5 mm particularly a lower limit of D=7 mm, more particularly a lower limit of D=9 mm, to an upper limit of D=14 mm, particularly to an upper limit of D=17 mm, more particularly to an upper limit of D=20 mm. According to a specific example, the distance D between two adjacent guiding elements of the plurality of guiding elements is D=10 mm. [0033] According to some embodiments which can be combined with any other embodiments described herein, the inclination angle (alpha) of the plurality of guiding elements may increase from an outer portion 143 of the shield arrangement 140 to an inner center element 141 of the shield arrangement 140. In this respect, it is to be understood that the expression that "the inclination angle may increase from an outer portion of the shield arrangement to an inner center element of the shield arrangement" describes a configuration in which the inclination angel gradually changes form a pointed angle to an angle of substantially 90° form the outer portion to the center element. For example, with exemplarily reference to Fig. 2, the first inclination angle (alpha- 1) may gradually change from an angle (alpha- 1) =20° at the outer portion 143 to an angle (alpha- 1) =90° to the inner center element 141 of the shield arrangement 140. Accordingly, the second inclination angle (alpha-2) may gradually change from an angle (alpha-2) =160° at the opposing outer portion 143 to an angle (alpha- 1) =90° to the inner center element 141 of the shield arrangement 140.

[0034] Accordingly, the trapping efficiency of the particle trap may be increased, because particles arriving with a smaller angle at the outer edge 131 of the cavity 130 of the particle trap 120 may not be reflected by the guiding elements but be guided into the particle trap. In other words, also particles arriving with a small impinging angle at the outer portion of the shield arrangement can effectively be guided into the particle trap. With, exemplary reference to Fig. 2 it is to be understood that according to some embodiments described herein the center element 141 may be arranged in the middle between the side walls of the cavity 130. In particular, the center element may be positioned on the longitudinal axis of the cavity.

[0035] With exemplarily reference to Fig. 2, according to embodiments which can be combined with any other embodiments described herein, the plurality of guiding elements 150 may include at least a first group 151 of guiding elements and at least a second group 152 of guiding elements. The at least first group 151 of guiding elements can be inclined with respect to a horizontal at the bottom 131 of the cavity 130 of the particle trap 120 by a first inclination angle (alpha- 1) from 20° to 90°. The at least second group 152 of guiding elements can be inclined with respect to a horizontal at the bottom of the cavity of the particle trap by a second inclination angle (alpha-2) from 90° to 160°. Further, according to some embodiments the at least first group 151 of guiding elements and the at least second group 152 of guiding elements may be symmetrically be arranged with respect to a center element 141 of the shield arrangement 140. [0036] For example, the first inclination angle (alpha-1) may be selected from a range between a lower limit of alpha-l=20°, particularly a lower limit of alpha-l=30°, more particularly a lower limit of alpha-l=40°, to an upper limit of alpha-l= 70°, particularly to an upper limit of alpha-l= 80°, more particularly to an upper limit of alpha-l= 90°. According to a specific example, the first inclination angle (alpha-1) is alpha- 1= 60°. According to another specific example, the first inclination angle (alpha-1) is alpha- 1= 45°.

[0037] The second inclination angle (alpha-2) may be selected from a range between a lower limit of alpha-2=90°, particularly a lower limit of alpha-2=100°, more particularly a lower limit of alpha-2=l 10°, to an upper limit of alpha-2= 140°, particularly to an upper limit of alpha-2= 150°, more particularly to an upper limit of alpha-2= 160°. According to a specific example, the second inclination angle (alpha-2) is alpha-2= 120°. According to another specific example, the second inclination angle (alpha-2) is alpha- 1= 135°.

[0038] Accordingly, from the exemplary embodiment shown is Fig. 2, it is to be understood the first inclination angle (alpha-1) and the second inclination angle (alpha-2) may be selected such that the lower ends 151 A of the at least first group 151 of guiding elements and the lower ends 152A of the at least second group 152 of guiding elements are directed towards each other. Accordingly, the trapping efficiency of the particle trap may be increased, and the particles can be guided into the particle trap such that the particles lose their kinetic energy.

[0039] According to embodiments which can be combined with any other embodiments described herein, the two or more adjacent guiding elements of the plurality of guiding elements 150 are configured for dissipating kinetic energy of a particle falling in between the two or more adjacent guiding elements. For example, the two or more adjacent guiding elements of the plurality of guiding elements 150 may be made of a material which is configured to absorb kinetic energy of impinging particles. Additionally or alternatively, the two or more adjacent guiding elements may include a surface structure which can absorb kinetic energy of impinging particles. For example, the two or more adjacent guiding elements may include a ribbed or riffled surface profile, as exemplarily described with reference to Fig. 7 for the bottom of the particle trap. Accordingly, the trapping efficiency can further be increased because particles falling into the particle trap lose their kinetic energy on their way to the bottom of the particle trap. In this regard, the skilled person understands that particle arriving at the bottom of particle trap with a lower kinetic energy can be trapped with a higher trapping efficiency than particles arriving at the bottom of particle trap with a higher kinetic energy.

[0040] The plurality of guiding elements 150 of the shield arrangement 140 is connected to each other for providing a shield arrangement insert. For example, the plurality of guiding elements of the shield arrangement can be connected to each other by connecting elements 145 as exemplarily shown in Figs. 4A and 4B. The connecting elements 145 may be of the same or a different material than the guiding elements. According to some embodiments, the shield arrangement may be manufactured to be a one-piece structure. According to some embodiments the shield arrangement insert may be retained within the cavity by the weight of the shield arrangement, i.e. by gravitational force. Additionally or alternatively, the shield arrangement insert may be fixed to a wall of the cavity, for example the side wall and/or the bottom wall of the cavity.

[0041] In Fig. 3 a cross-sectional view along the line A- A of the enlarged view of the particle trap 120 as illustrated in Fig. 2 is shown. As exemplarily shown in Fig. 3, the shield arrangement 140 is at least partially arranged within the cavity 130. In the exemplary embodiment shown in Fig. 3, the shield arrangement 140 rests on the side walls of the cavity 130. However, it is to be understood that according to another implementation the shield arrangement may rest on the bottom of the cavity which may be beneficial with respect a reduction or even elimination of the influence of gas flows on the trapping efficiency since gas flows on the bottom of the cavity of the particle trap can be avoided. According to some embodiments, the shield arrangement 140 may be provided with a spacer 144 for providing a preselected distance between the shield arrangement 140 and the bottom of the cavity 130. Accordingly, a particle trapping space between the shield arrangement 140 and the bottom 131 of the cavity 130 may be provided. [0042] Figs. 4A shows a schematic top view of an exemplarily embodiment of a particle trap 120 of a high-voltage switching device 100 which can be combined with any other embodiments described herein. As exemplarily shown in Fig. 4A, according to some embodiments the cavity 130 may have a substantially rectangular shape. Accordingly, the shield arrangement 140 may be adapted to at least partially fit into the rectangular cavity. For example the shield arrangement 140 may be configured to have a plurality of guiding elements extending transversal to a length direction of the rectangular cavity, as exemplarily shown in Fig. 4A. However, although not explicitly shown, it is to be understood that the plurality of guiding elements may alternatively also be arranged to extend parallel to the length direction of the rectangular cavity.

[0043] Fig. 4B shows a schematic top view of another exemplarily embodiment of a particle trap 120 of a high-voltage switching device 100 which can be combined with any other embodiments described herein. In particular, Fig. 4B shows a configuration of the particle trap having a circular cavity 130 in which a circular shield arrangement 140 is arranged. As exemplarily shown in Fig. 4B, the plurality of guiding elements may be arranged concentrically. For example, the plurality of guiding elements may have a propeller or turbine blade-like shape. However, the skilled person understands that other shapes of cavities and correspondingly adapted shield arrangements may be provided, e.g. a square-like shape or a oval like shape or any other suitable shape.

[0044] Fig. 5 shows an enlarged view of a particle trap 120 of a high-voltage switching device 100 according to further embodiments which can be combined with any other embodiments described herein. As exemplarily shown in Fig. 5, according to some embodiments the plurality of guiding elements 150 may be arranged such that the angle of inclination (alpha) is directed to a center element 141 of the shield arrangement 140. For example, the center element of the shield arrangement 140 may include a triangular shaped guiding element which is arranged such that the tip of the triangular guiding element points away from the bottom of the cavity. In particular, at least a first group 151 of guiding elements can include a first inclination angle (alpha- 1) and at least a second group 152 of guiding elements can include a second inclination angle (alpha-2). For example, the first inclination angle (alpha- 1) and the second inclination angle (alpha-2) may be selected such that the upper ends 15 IB of the at least first group 151 of guiding elements and the upper ends 152B of the at least second group 152 of guiding elements are directed towards each other. Further, as exemplarily shown in Fig. 5, according to some embodiments which can be combined with other embodiments described herein, the outer guiding elements of the shield of shield arrangement may be configured differently than the first group 151 of guiding elements and/or the second group 152 of guiding elements. Particular, the outer guiding elements of the shield arrangement may have a rhombic-like configuration, as shown in Fig. 5.

[0045] Fig. 6 shows an enlarged view of a particle trap 120 of a high-voltage switching device 100 according to yet further embodiments which can be combined with any other embodiments described herein. In particular, Fig. 6 shows an embodiment in which two or more adjacent guiding elements of the plurality of guiding elements 150 are configured and arranged for providing a tapered particle guiding passage to the bottom 131 of the cavity 130 of the particle trap 120. Particularly, according to some embodiments, the shield arrangement may include a first group 151 of guiding elements which have a smaller longitudinal extension than a second group 152 of guiding elements. For example, as exemplarily shown in Fig. 6, a first guiding element belonging to the first group 151 of guiding elements may be arranged in between two second guiding elements belonging to the second group 152 of guiding elements. Accordingly, it is to be understood that the first guiding elements of the first group 151 and the second guiding elements of the second group 152 may be arranged in an alternating manner.

[0046] With exemplary reference to Fig. 6, according to some embodiments which can be combined with other embodiments described herein, the first guiding elements of the first group 151 may be configured to have a thinner upper end than a lower bottom end. In particular, the first guiding elements of the first group 151 may have a tapered shape with a reduced width at the upper end. The second guiding elements of the second group 152 may be configured to have a triangular- like bottom end, wherein the basis of the triangular- like bottom end faces the bottom of the cavity of the particle trap. Accordingly, as can be seen from Fig. 6, the triangular- like bottom ends of the second guiding elements provide an at least partially inclined particle guiding passage 155 to the bottom 131 of the cavity 130 of the particle trap 120. As exemplarily shown in Fig. 6, the first guiding elements of the first group 151 and/or the second guiding elements of the second group 152 may have main portions which extend in a substantially vertical direction with respect to the bottom of the cavity. According to some embodiments, one or more guiding elements of the plurality of guiding elements which are arranged at an outer portion 143 of the shield arrangement 140 can be at least partially inclined with respect to a horizontal at the bottom 131. For example, the one or more guiding elements of the plurality of guiding elements which are arranged at the outer portion 143 may be inclined by an inclination angle (alpha) as described herein.

[0047] Fig.7 shows an enlarged view of a particle trap 120 of a high-voltage switching device 100 according to yet further embodiments which can be combined with any other embodiments described herein. In particular, Fig. 7 shows an exemplarily embodiment having ribbed profile at the bottom 131 of the cavity 130 of the particle trap 120. Accordingly, the trapping efficiency can further be increased. In other words, by providing a particle trap having cavity with a ribbed profile at the bottom the probability or tendency of a particle leaving the trap can be decreased. Additionally or alternatively, the bottom of the cavity of the particle trap may be configured to be sticky for the particles. Thereby, the particle trapping efficiency may further be increased. According some embodiments which can be combined with any other embodiments described herein, the particle trap may be provided with a cover plate including openings, as exemplarily shown in Fig. 7. Thereby, the trapping efficiency may be further increased.

[0048] According to embodiments which can be combined with any other embodiments described herein, the two or more adjacent guiding elements of the plurality of guiding elements (150) include at least one at least semi-conductive material, particularly at least one conductive material, selected form the group consisting of: metal, polymer, and ceramics. In particular, the material of the shield arrangement may be a material being thermal stable for temperatures up to 100°C, particularly up to 200°C more particularly up to 300° C. Further, the material of the shield arrangement may be selected to be inert with respect to sulfur hexafluoride (SF6)-gas and to be electrically conductive.

[0049] According to embodiments which can be combined with other embodiments described herein, the particle trap is arranged within the metallic encapsulation of the gas- insulated high voltage switching device at a position at which the curvature of the electric field lines onto the encapsulation changes from convex to concave. Such a position of the particle trap may be beneficial since it has been found that particles preferably accumulate where electrical field lines change the orientation of their curvature. Additionally or alternatively the particle trap can be arranged within the encapsulation housing at a position where particle generation or injection are expected mostly to appear, which may be beneficial for increasing the particle trapping efficiency.

[0050] In view of the above, it is to be understood that by providing a particle trap cavity with a shield arrangement having guiding elements which are configured for reflecting and guiding impinging particles to the bottom of the particle trap, the trapping efficiency for trapping high kinetic energy particles can be significantly increased. Further, it is to be understood that embodiments as described herein are beneficially configured for promoting guidance of particles to the bottom of the particle trap while a way out of the particle trap for the particles is hindered by the configuration of the shield arrangement as described herein. In other words, the shield arrangement as described herein is designed in such a way that the chance of a particle, leaving the particle trap again, is significantly reduced. Unlike the flat horizontal bottom of conventional particle traps, the added shield arrangement, particularly including guiding elements as described herein, has the functionality to anticipate on the dynamic behavior of kinetic particles and to reflect/guide the particles further down the particle trap, while reducing the chance of a particle leaving the trap again. Due to the reflections of the particles on the guiding elements the kinetic energy of the particles will be significantly reduced, leading to a much higher retention characteristic of the particle trap. Further, the skilled person understands that some embodiments described herein are configured such that gas flows on the bottom of the cavity of the particle trap can be avoided such that the trapping efficiency can be increased. Accordingly, it is to be understood that embodiments of the high-voltage switching device as described herein provide for an improved operational reliability. In particular, an improved operational reliability of high- voltage switching devices can be provided by employing a particle trap having a shield arrangement as described herein.

[0051] Further, it is to be understood that an existing high- voltage switching device having an encapsulation housing including a cavity for particle trapping may be retrofitted with a shield arrangement as described herein such that an improved particle trapping efficiency, and thus an improved operational reliability of retrofitted high-voltage switching devices can be provided.

[0052] Figs. 8A shows a schematic block diagrams illustrating a method 200 for separating particles in a high- voltage switching device according to embodiments described herein. In particular, the method includes guiding 210 particles to a bottom of a cavity of a particle trap provided in an encapsulation housing of the high-voltage switching device. Further, guiding 210 is conducted by two or more adjacent guiding elements of a plurality of guiding elements of a shield arrangement which is at least partially arranged within the cavity. Additionally, the method 200 includes employing 220 the shield arrangement for hindering the particles guided into the particle trap from escaping the particle trap, wherein the shield arrangement includes a plurality of guiding elements for guiding particles into the cavity, and wherein two or more adjacent guiding elements of the plurality of guiding elements provide a particle guiding passage to the bottom of the cavity of the particle trap. It is to be understood, that the shield arrangement may be configured as described herein, particularly as described with respect to the embodiments shown in Figs. 2 to 7.

[0053] With exemplarily reference to Fig. 8B, according to embodiments which can be combined with other embodiments described herein, guiding 210 particles to a bottom of the cavity of the particle trap provided in the encapsulation housing of the high-voltage switching device includes dissipating 211 kinetic energy of the particles by the two or more adjacent guiding elements of the plurality of guiding elements.

[0054] In view of the above, it is to be understood that embodiments of the method for separating particles in a high- voltage switching device as described herein, provide for increasing particle trapping efficiency and improved particle retention such that the operational reliability of high- voltage switching devices can be improved.

[0055] This written description uses examples to disclose the disclosure, including the best mode, and also to enable any person skilled in the art to practice the described subject-matter, including making and using any devices or systems and performing any incorporated methods. While various specific embodiments have been disclosed in the foregoing, mutually non-exclusive features of the embodiments described above may be combined with each other. The patentable scope is defined by the claims, and other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

1. A high- voltage gas-insulated switchgear device (100) having a metallic encapsulation (110) comprising a particle trap (120) for holding particles, wherein the particle trap (120) comprises a cavity (130) in the encapsulation (110) and a shield arrangement (140), wherein the shield arrangement (140) is at least partially arranged within the cavity (130), wherein the shield arrangement (140) comprises a plurality of guiding elements (150) for guiding particles into the cavity (130), and wherein two or more adjacent guiding elements of the plurality of guiding elements (150) provide a particle guiding passage (155) to the bottom (131) of the cavity (130) of the particle trap (120), wherein the plurality of guiding elements (150) of the shield arrangement are connected to each other for providing a shield arrangement insert, and wherein at least a portion of the two or more adjacent guiding elements of the plurality of guiding elements (150) are configured for providing an at least partially inclined particle guiding passage (155) with respect to a horizontal at a bottom (131) of the cavity (130) of the particle trap (120).

2. The high- voltage gas-insulated switchgear device (100) according to claim 1, wherein the at least partially inclined particle guiding passage (155) is inclined with respect to a horizontal at the bottom (131) of the cavity (130) of the particle trap (120) by an inclination angle (alpha) from 20° to 160°, particularly by an angle from 30° to 150°.

3. The high- voltage gas-insulated switchgear device (100) according to claim any of claims 1 to 2, wherein the two or more adjacent guiding elements are configured for dissipating kinetic energy of a particle impinging on at least one of the two or more adjacent guiding elements.

4. The high- voltage gas-insulated switchgear device (100) according to claim 1, wherein the shield arrangement (140) is fixed to a wall of the cavity (130) in the encapsulation (110).

5. The high- voltage gas-insulated switchgear device (100) according to any of claims 1 to 4, wherein the plurality of guiding elements (150) comprise at least a first group (151) of guiding elements and at least a second group (152) of guiding elements, wherein the at least first group (151) of guiding elements are at least partially inclined with respect to a horizontal at the bottom (131) of the cavity (130) of the particle trap (120) by a first inclination angle (alpha-1) from 20° to 90°, and wherein the at least second group (152) of guiding elements are at least partially inclined with respect to the bottom of the cavity of the particle trap by a second inclination angle (alpha-2) from 90° to 160°.

6. The high- voltage gas-insulated switchgear device (100) according to claim 5, wherein the first group (151) of guiding elements and the second group (152) of guiding elements are symmetrically arranged with respect to a center element (141) of the shield arrangement (140).

7. The high-voltage gas-insulated switchgear device (100) according to any of claims 1 to 6, wherein the inclination angle (alpha) of the plurality of guiding elements may increase from an outer portion (143) of the shield arrangement (140) to an inner center element (141) of the shield arrangement (140).

8. The high-voltage gas-insulated switchgear device (100) according to any of claims 1 to 7, wherein the two or more adjacent guiding elements of the plurality of guiding elements (150) comprise at least a guiding surface which is parallel to a guiding surface of an adjacent guiding element.

9. The high- voltage gas-insulated switchgear device (100) according to any of claims 1 to 8, wherein two or more adjacent guiding elements of the plurality of guiding elements (150) are arranged for providing a tapered particle guiding passage to the bottom (131) of the cavity (130) of the particle trap (120).

10. The high-voltage gas-insulated switchgear device (100) according to any of claims 1 to 9, wherein two or more adjacent guiding elements of the plurality of guiding elements (150) comprise at least one at least semi-conductive material, particularly at least one conductive material, selected form the group consisting of: metal, polymer, and ceramics.

11. The high- voltage switching gas-insulated switchgear device (100) according to any of claims 1 to 10, wherein a distance between two adjacent guiding elements of the plurality of guiding elements (150) is from 5 mm to 20 mm.

12. The high-voltage gas-insulated switchgear device (100) according to any of claims 1 to 11, wherein the particle trap (120) is arranged within the metallic encapsulation (110) of the high voltage switching device (100) at a position at which the curvature of the electric field lines onto the encapsulation changes the orientation.

13. A method (200) for separating particles in a high- voltage gas-insulated metal-enclosed switchgear device, wherein the method comprises:

- guiding (210) particles to a bottom of a cavity of a particle trap provided in a metallic encapsulation of the high- voltage switching device, wherein guiding (210) is conducted by two or more adjacent guiding elements of a plurality of guiding elements of a shield arrangement which is at least partially arranged within the cavity; and

- employing (220) the shield arrangement for hindering the particles guided into the particle trap from escaping the particle trap, wherein the shield arrangement comprises a plurality of guiding elements for guiding particles into the cavity, wherein two or more adjacent guiding elements of the plurality of guiding elements provide a particle guiding passage to the bottom of the cavity of the particle trap, and wherein the plurality of guiding elements (150) of the shield arrangement are connected to each other for providing a shield arrangement insert), and

wherein at least a portion of the two or more adjacent guiding elements of the plurality of guiding elements (150) are configured for providing an at least partially inclined particle guiding passage (155) with respect to a horizontal at a bottom (131) of the cavity (130) of the particle trap (120).