Switching arrangement of a disconnect switch for three-phase alternating current

Abstract

The invention relates to a switching arrangement (1) of a disconnect switch (1) for three-phase alternating current. The switching arrangement (1) comprises an electrical fixed contact (3) for each phase of the alternating current, at least one corresponding electrical moving contact (5, 6) for each fixed contact (3), which is movable between an off position, in which it is separated from the fixed contact (3), and an on position, in which it is in contact with the fixed contact (3), and an insulating element (7) made of an electrically insulating material. The insulating element (7) has a plate-shaped first region (13) which has a recess (19) for each fixed contact (3), through which the fixed contact (3) extends to the at least one corresponding moving contact (5, 6).The first area (13) of the insulating element (7) has a first surface (21) facing away from the moving contacts (5, 6), from which two second areas (15) protrude, between which first sections (25) of all fixed contacts (3) are arranged.

Description

[0001] The invention relates to a disconnect switch for three-phase alternating current and in particular to a switching arrangement of such a disconnect switch.

[0002] Disconnectors for three-phase alternating current typically have one fixed contact and at least one movable contact for each phase of the alternating current. Each movable contact can move between an off position, in which it is disconnected from the corresponding fixed contact, and an on position, in which it is in contact with that fixed contact. The fixed and movable contacts must be dielectrically separated from each other to prevent electrical arcing between them in the off position and to prevent a phase short circuit, for example, by an arc, when the disconnector is switched off. In a gas-insulated disconnector, the fixed and movable contacts are arranged in a gas chamber filled with an insulating gas for this purpose. Sulfur hexafluoride was frequently used as the insulating gas.Sulfur hexafluoride, however, is not environmentally friendly because it is a potent greenhouse gas, and its use as an insulating gas is therefore often prohibited. When using other gases, the distances between the fixed and moving contacts of the different phases must be increased compared to using sulfur hexafluoride, or the disconnect switch must be modified in some other suitable way.

[0003] The invention is based on the objective of providing an improved switching arrangement of a disconnect switch for three-phase alternating current.

[0004] The problem is solved according to the invention by a switching arrangement with the features of claim 1 and a disconnect switch with the features of claim 10.

[0005] Advantageous embodiments of the invention are the subject of the dependent claims.

[0006] A switching arrangement according to the invention of a disconnect switch for three-phase alternating current comprises - one fixed electrical contact for each phase of the alternating current, - for each fixed contact at least one corresponding electrical moving contact, which is movable between an off position in which it is separated from the fixed contact and an on position in which it is in contact with the fixed contact, and - an insulating element made of an electrically insulating material, wherein - the insulating element has a plate-shaped first area which has a recess for each fixed contact through which the fixed contact extends to the at least one corresponding moving contact, - the first area of ​​the insulating element has a first surface facing away from the moving contacts and a second surface facing the moving contacts and - the insulating element has two second areas projecting from the first surface, between which first sections of all fixed contacts are arranged.

[0007] The insulating element enhances the dielectric shielding of the fixed contacts of the switching assembly from the moving contacts and other electrically conductive components of the disconnect switch, such as the housing wall of the disconnect switch. If the fixed and moving contacts are located in a gas-filled chamber of the disconnect switch, the insulating element amplifies the effect of the insulating gas. This allows for a more compact design of the disconnect switch compared to a design without the insulating element. The first section of the insulating element increases the dielectric strength primarily in the space between the fixed and moving contacts, while the second section provides lateral dielectric shielding for the fixed contacts. The recesses in the insulating element allow the moving contacts to make contact with the fixed contacts.

[0008] The switching arrangement is preferably designed for voltages of 1 kV and above, and particularly preferably for voltages from 1 kV up to and including 52 kV. It is especially preferred that the switching arrangement is located in an insulating gas or an insulating and switching gas that contains no fluorine components and / or contains nitrogen and carbon dioxide during filling, or contains only nitrogen and carbon dioxide and other air components.

[0009] In one embodiment of the switching arrangement according to the invention, the insulating element has third regions projecting from the second surface, between each of which a second section of a fixed contact is arranged, against which at least one corresponding moving contact rests in its on position. The third regions of the insulating element thus extend from the second surface to the moving contacts, in particular between sections of the fixed contacts against which the moving contacts rest in their on positions. In this way, the third regions of the insulating element dielectrically shield the fixed contacts and the moving contacts (in their on positions) of the different phases from each other.

[0010] In a further embodiment of the switching arrangement according to the invention, the fixed contacts are arranged in mutually parallel planes, and the first region of the insulating element is perpendicular to these planes. The phrase "a fixed contact is arranged in a plane" means that the plane passes through the fixed contact and that the fixed contact has a greater extent in the plane than perpendicular to the plane. The fixed contacts are thus designed as relatively narrow, elongated objects arranged parallel to each other. The first region of the insulating element is perpendicular to the planes of the fixed contacts.

[0011] In a further embodiment of the switching arrangement according to the invention, the third regions of the insulating element are each plate-shaped and parallel to the planes in which the fixed contacts are arranged. The third regions of the insulating element thus function in particular as "dielectric partitions" between the sections of the fixed contacts against which the moving contacts bear in their switched-on positions.

[0012] In a further embodiment of the switching arrangement according to the invention, the second regions of the insulating element are each plate-shaped and perpendicular to the planes in which the fixed contacts are arranged and to the first region of the insulating element. For example, the first region and the second regions of the insulating element form a U-profile. This allows the second regions of the insulating element to form "dielectric walls" between which the sections of the fixed contacts facing away from the moving contacts extend.

[0013] In a further embodiment of the switching arrangement according to the invention, the insulating element is made of a plastic. For example, the plastic is a polycarbonate or a polyamide. An insulating element made of a plastic is particularly cost-effective to manufacture.

[0014] In a further embodiment of the switching arrangement according to the invention, the movement of each moving contact between its off position and on position is a pivoting movement about a pivot axis. This enables a space-saving design of the switching arrangement.

[0015] A disconnect switch according to the invention for three-phase alternating current has a switching arrangement according to the invention. In one embodiment of a disconnect switch according to the invention, the switching arrangement is located in a gas chamber of the disconnect switch, which is filled with an insulating gas during operation of the disconnect switch. The insulating gas enables a more compact design of the disconnect switch. As already explained above, the effect of the insulating gas is enhanced by the insulating element. The further advantages of a disconnect switch according to the invention result from the advantages of a switching arrangement according to the invention mentioned above.

[0016] The properties, features, and advantages of this invention described above, as well as the manner in which they are achieved, will become clearer and more readily understandable in connection with the following description of exemplary embodiments, which are explained in more detail in conjunction with the drawings. These drawings show: Fig. 1 a perspective view of fixed contacts and moving contacts of a first embodiment of a switching arrangement of a disconnect switch, Fig. 2 a perspective view of an insulating element of a switching arrangement of a disconnect switch, Fig. 3 a perspective view of a first embodiment of a switching arrangement of a disconnect switch, Fig. 4 a perspective view of a second embodiment of a switching arrangement of a disconnect switch.

[0017] Corresponding parts are marked with the same reference symbols in the figures.

[0018] The Fig. 1, Fig. 2 to Fig. Figure 3 shows perspective views of a first embodiment of a switching arrangement 1 according to the invention, a disconnect switch for three-phase alternating current, and of components of the switching arrangement 1. The switching arrangement 1 comprises fixed contacts 3, moving contacts 5, and an insulating element 7.

[0019] Fig. 1 ( Fig. Figure 1 shows a perspective view of the fixed contacts 3 and moving contacts 5. The switching arrangement 1 has one fixed contact 3 and one corresponding moving contact 5 for each phase of the alternating current. The fixed contact 3 and the moving contact 5 of each phase are arranged in a plane 9, with the planes 9 of the phases being parallel to each other.

[0020] The moving contact 5 of each phase is oriented around a pivot axis 11 between a in Fig. The moving contacts 5 are movable in the off position shown in Figure 1, in which they are disconnected from the fixed contact 3 of the phase, and in an on position, in which they are in contact with this fixed contact 3. The pivoting movements of the moving contacts 5 from the off position to the on position are shown in Figure 1. Fig. 1 represented by dashed arrow symbols.

[0021] Fig. 2 ( Fig. Figure 2 shows a perspective view of the insulating element 7. The insulating element 7 is made of an electrically insulating material. For example, the insulating element 7 is made of a plastic, such as polycarbonate or polyamide.

[0022] The insulating element 7 has a first region 13, two second regions 15, and three third regions 17. The first region 13, the second regions 15, and the third regions 17 are each plate-shaped and essentially rectangular. The first region 13 has three recesses 19. The second regions 15 each extend perpendicularly from a first surface 21 of the first region 13 and are parallel to each other. The second regions 15 and the first region 13 form a U-profile, with the second regions 15 forming the legs of the U-profile and the first region 13 forming the web of the U-profile. The third regions 17 extend perpendicularly from a second surface 23 of the insulating element 7 facing away from the first surface 21 and are parallel to each other and perpendicular to the second regions 15. A recess 19 is arranged between each pair of third regions 17.

[0023] Fig. 3 ( Fig. Figure 3 shows a perspective view of the switching arrangement 1 in the off position of the moving contacts 5. The insulating element 7 is essentially arranged between the fixed contacts 3 and the moving contacts 5, with the first region 13 of the insulating element 7 perpendicular to the planes 9 (see Figure 3). Fig. 1) stands, in which the fixed contact 3 and the moving contact 5 are arranged for one phase of the alternating current.

[0024] The first surface 21 of the insulating element 7 faces away from the moving contacts 5. The second areas 15 of the insulating element 7, projecting from the first surface 21, are each perpendicular to the planes 9 in which the fixed contact 3 and the moving contact 5 are arranged for one phase of the alternating current. First sections 25 of all fixed contacts 3 are arranged between the second areas 15 of the insulating element 7.

[0025] The second surface 23 of the first region 13 of the insulating element 7 faces the moving contacts 5. A fixed contact 3 extends through each recess 19 of the first region 13 of the insulating element 7 towards the corresponding moving contact 5. Between each pair of adjacent third regions 17 of the insulating element 7, a second section 27 of a fixed contact 3 is arranged, against which a moving contact 5 rests in its on position.

[0026] Fig. 4 ( Fig. Figure 4) shows a perspective view of a second embodiment of a switching arrangement 1 according to the invention, a disconnect switch for three-phase alternating current. This embodiment differs from the one shown based on the Fig. 1, Fig. 2 to Fig. The embodiment described in section 3 differs essentially only in that the switching arrangement 1 has two moving contacts 5, 6 for each phase of the alternating current, which simultaneously switch between a Fig. The moving contacts 5 and 6 are movable in the off position shown in Figure 4, in which they are each disconnected from the fixed contact 3 of the phase, and in the on position, in which they are each connected to this fixed contact 3. The movements of the moving contacts 5 and 6 are pivoting movements, with the first moving contacts 5 of all three phases pivoting about a common first pivot axis 11 and the second moving contacts 6 of all three phases pivoting about a common second pivot axis 12 parallel to the first pivot axis 11. The pivoting movements of the first moving contacts 5 and the second moving contacts 6 are opposite to each other and in Fig. 4 for pivoting movements from the off position to the on position for two moving contacts 5, 6 represented by dashed arrow symbols.

[0027] The design of a switching arrangement1 with two moving contacts 5, 6 per phase is advantageous if the moving contacts 5, 6 conduct high electrical currents, because then the currents can be divided between the two moving contacts 5, 6.

[0028] In both cases, in the Fig. 1, Fig. 2, Fig. 3 to Fig. In the 4 illustrated embodiments, the fixed contacts 3, the moving contacts 5, 6 and the insulating element 7 are arranged in a gas space which is filled with an insulating gas during operation of the disconnect switch.

[0029] Although the invention has been further illustrated and described in detail by means of preferred embodiments, the invention is not limited by the disclosed examples and other variations can be derived from them by a person skilled in the art without leaving the scope of protection of the invention. Reference symbol list 1 Switching arrangement 3 fixed contacts 5, 6 Moving contact 7 Insulating element Level 9 11, 12 Swivel axis 13 first area 15 second area 17 third area 19 Exclusion 21 first surface 23 second surface 25 first section 27 second section

Claims

[1] Switching arrangement (1) of a three-phase alternating current disconnect switch, the switching arrangement (1) comprising - for each phase of the alternating current, a fixed electrical contact (3), - for each fixed contact (3) at least one corresponding electrical moving contact (5, 6) which is movable between an off position, in which it is separated from the fixed contact (3), and an on position, in which it is in contact with the fixed contact (3), and - an insulating element (7) made of an electrically insulating material, wherein - the insulating element (7) has a plate-shaped first area (13) which has a recess (19) for each fixed contact (3) through which the fixed contact (3) extends to the at least one corresponding moving contact (5, 6), - the first area (13) of the insulating element (7) has a first surface (21) facing away from the moving contacts (5, 6) and a second surface (23) facing the moving contacts (5, 6) and - the insulating element (7) has two second areas (15) projecting from the first surface (21), between which first sections (25) of all fixed contacts (3) are arranged. [2] Switching arrangement (1) according to claim 1, wherein the insulating element (7) has third areas (17) projecting from the second surface (23), between each of which a second section (27) of a fixed contact (3) is arranged, on which at least one moving contact (5, 6) is in its on position. [3] Switching arrangement (1) according to claim 1 or 2, wherein the fixed contacts (3) are arranged in mutually parallel planes (9) and the first region (13) of the insulating element (7) is perpendicular to these planes (9). [4] Switching arrangement (1) according to claims 2 and 3, wherein the third areas (17) of the insulating element (7) are each plate-shaped and parallel to the planes (9) in which the fixed contacts (3) are arranged. [5] Switching arrangement (1) according to claim 3 or 4, wherein the second areas (15) of the insulating element (7) are each plate-shaped and perpendicular to the planes (9) in which the fixed contacts (3) are arranged and to the first area (13) of the insulating element (7). [6] Switching arrangement (1) according to one of the preceding claims, wherein the first region (13) and the second regions (15) of the insulating element (7) form a U-profile. [7] Switching arrangement (1) according to one of the preceding claims, wherein the insulating element (7) is made of a plastic. [8] Switching arrangement (1) according to one of the preceding claims, wherein the insulating element (7) is made of a polycarbonate or a polyamide. [9] Switching arrangement (1) according to one of the preceding claims, wherein the movement of each moving contact (5, 6) between its off position and on position is a pivoting movement about a pivot axis (11, 12). [10] Disconnect switch for three-phase alternating current with a switching arrangement (1) according to one of the preceding claims. [11] Disconnect switch according to claim 10, wherein the switching arrangement (1) is arranged in a gas chamber of the disconnect switch which is filled with an insulating gas during operation of the disconnect switch.

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