Vacuum Interrupter Fuse

Abstract

A CutOut, comprising a first electrical connection rod; a second electrical connection rod; a first contact; a second contact; and a fuse wire; wherein the first contact is mounted to the first electrical connection rod; wherein the second contact is mounted to the second electrical connection rod; wherein when a current below a threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the vacuum-based fuseCutOut is configured to hold the first contact a fixed distance from the second contact and the fuse wire is configured to electrical connect the first electrical connection rod to the second electrical connection rod; and wherein when a current at or above the threshold flows through the vacuum-based fuseCutOut the fuse wire is configured to electrically disconnect the first electrical connection rod from the second electrical connection rod.

Claims

1. A vacuum-based fuseCutOut, comprising: a first electrical connection rod; a second electrical connection rod; a first contact; a second contact; and a fuse wire; wherein the first contact is mounted to the first electrical connection rod; wherein the second contact is mounted to the second electrical connection rod; wherein when a current below a threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the vacuum-based fuseCutOut is configured to hold the first contact a fixed distance from the second contact and the fuse wire is configured to electrical connect the first electrical connection rod to the second electrical connection rod; and wherein when a current at or above the threshold flows through the vacuum-based fuseCutOut the fuse wire is configured to electrically disconnect the first electrical connection rod from the second electrical connection rod.

2. The vacuum-based fuseCutOut according to claim 1, wherein when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the vacuum-based fuseCutOut is configured to move the second contact away from the first contact.

3. The vacuum-based fuseCutOut according to claim 2, wherein when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the vacuum-based fuseCutOut is configured to move the second electrical connection rod away from the first electrical connection rod.

4. The vacuum-based fuseCutOut according to claim 2, wherein the second contact is fixedly mounted to the second electrical connection rod.

5. The vacuum-based fuseCutOut according to claim 2, wherein the vacuum-based fuseCutOut comprises a release spring, and wherein when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the release spring is configured to move the second contact away from the first contact.

6. The vacuum-based fuseCutOut according to claim 1, wherein the first contact is a transverse magnetic field, TMF, contact, and wherein the second contact is a TMF contact.

7. The vacuum-based fuseCutOut according to claim 1, wherein the first contact is an axial magnetic field, AMF, contact, and wherein the second contact is an AMF contact.

8. The vacuum-based fuseCutOut according to claim 1, wherein the first contact is a transverse magnetic field, TMF, contact, and wherein the second contact is an AMF contact.

9. The vacuum-based fuseCutOut according to 1, wherein the first contact is an AMF contact, and wherein the second contact is a TMF contact.

10. The vacuum-based fuseCutOut according to claim 1, wherein the vacuum-based fuseCutOut comprises a steel wire, and wherein when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the first contact is held the fixed distance from the second contact at least in part by the steel wire.

11. The vacuum-based fuseCutOut according to claim 1, wherein when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the first contact is held the fixed distance from the second contact at least in part by the fuse wire.

12. The vacuum-based fuseCutOut according to claim 1, wherein the vacuum-based fuseCutOut comprises an outer body (110), and wherein the outer body is configured to maintain a vacuum within the body when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut.

13. The vacuum-based fuseCutOut according to claim 12, wherein the vacuum-based fuseCutOut comprises an insulation part (120) located within the outer body, and wherein the insulation part surrounds the first contact and the second contact when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut.

14. Vacuum-based fuseCutOut according to claim 13, wherein the insulation part surrounds the first contact and the second contact during movement of the second contact away from the first contact when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod.

15. A vacuum interrupter device, comprising: a vacuum-based fuseCutOut, comprising: a first electrical connection rod; a second electrical connection rod; a first contact; a second contact; and a fuse wire; wherein the first contact is mounted to the first electrical connection rod; wherein the second contact is mounted to the second electrical connection rod; wherein when a current below a threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuse - CutOut the vacuum-based fuseCutOut is configured to hold the first contact a fixed distance from the second contact and the fuse wire is configured to electrical connect the first electrical connection rod to the second electrical connection rod; and wherein when a current at or above the threshold flows through the vacuum-based fuseCutOut the fuse wire is configured to electrically disconnect the first electrical connection rod from the second electrical connection rod; a first electrical connector connected to the first electrical connection rod of the vacuum-based fuseCutOut; a second electrical connector connected to the second electrical connection rod of the vacuum-based fuseCutOut; and at least one insulation structure surround at least part of the first electrical connector.

16. The vacuum interrupter device according to claim 15, wherein when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the vacuum-based fuseCutOut is configured to move the second contact away from the first contact.

17. The vacuum interrupter device according to claim 16, wherein when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the vacuum-based fuseCutOut is configured to move the second electrical connection rod away from the first electrical connection rod.

18. The vacuum interrupter device according to claim 16, wherein the second contact is fixedly mounted to the second electrical connection rod.

19. The vacuum interrupter device according to claim 16, wherein the vacuum-based fuseCutOut comprises a release spring, and wherein when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the release spring is configured to move the second contact away from the first contact.

20. The vacuum interrupter device according to claim 15, wherein the vacuum-based fuseCutOut comprises a steel wire, and wherein when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the first contact is held the fixed distance from the second contact at least in part by the steel wire.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

[0019] FIG. 1 is an outline view from a side perspective of a complete vacuum-based fuseCutOut device that has a vacuum interrupter fuse in accordance with the disclosure.

[0020] FIG. 2 is an enlarged section view of the vacuum-based fuseCutOut as shown in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

[0021] As discussed above currently used expulsion fuse CutOut fuses have the advantage to interrupt load- or short circuit current. The clear drawback is the release of chemical components during load- and short circuit current interruption and the plasma flame to the surrounding which might be damage nearby components. In addition, and especially during the short circuit current interruption it's noisy and sounds like an explosion.

[0022] Presently available current limiting fuses have full functionality but are bulky and the performance is quite limited and costly compared to the expulsion fuse CutOut device and can be close to a factor of 10 times higher in cost.

[0023] To overcome these disadvantages a new vacuum-based fuseCutOut and vacuum interrupter device having such a vacuum-based fuseCutOut were developed.

[0024] FIGS. 1-2 relate to the new vacuum-based fuseCutOut and vacuum-based fuseCutOut having such a vacuum fuse.

[0025] An exemplar vacuum-based fuseCutOut 40 comprises: a first electrical connection rod 230; a second electrical connection rod 210; a first contact 100; a second contact 130; and a fuse wire 220.

[0026] The first contact is mounted to the first electrical connection rod. The second contact is mounted to the second electrical connection rod. When a current below a threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the vacuum-based fuseCutOut is configured to hold the first contact a fixed distance from the second contact and the fuse wire is configured to electrical connect the first electrical connection rod to the second electrical connection rod. When a current at or above the threshold flows through the vacuum-based fuseCutOut the fuse wire is configured to electrically disconnect the first electrical connection rod from the second electrical connection rod.

[0027] In an example, when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the vacuum-based fuseCutOut is configured to move the second contact away from the first contact.

[0028] In an example, when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the vacuum-based fuseCutOut is configured to move the second electrical connection rod away from the first electrical connection rod.

[0029] In an example, the second contact is fixedly mounted to the second electrical connection rod.

[0030] In an example, the vacuum-based fuseCutOut comprises a release spring 180, and when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the release spring is configured to move the second contact away from the first contact.

[0031] In an example, the first contact is a transverse magnetic field, TMF, contact, and the second contact is a TMF contact.

[0032] In an example, the first contact is an axial magnetic field, AMF, contact, and the second contact is an AMF contact.

[0033] In an example, the first contact is a transverse magnetic field, TMF, contact, and the second contact is an AMF contact.

[0034] In an example, the first contact is an AMF contact, and the second contact is a TMF contact.

[0035] In an example, there is hybrid contact installed with combination of AMF/TMF or TMF/TMF.

[0036] In an example, the vacuum-based fuseCutOut comprises a steel wire, and wherein when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the first contact is held the fixed distance from the second contact at least in part by the steel wire.

[0037] In an example, when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the first contact is held the fixed distance from the second contact at least in part by the fuse wire.

[0038] In an example, the vacuum-based fuseCutOut comprises an outer body 110, and the outer body is configured to maintain a vacuum within the body when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut.

[0039] In an example, the vacuum-based fuseCutOut comprises an insulation part 120 located within the outer body, and wherein the insulation part surrounds the first contact and the second contact when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut.

[0040] In an example, the insulation part surrounds the first contact and the second contact during movement of the second contact away from the first contact when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod.

[0041] A complete vacuum-based fuseCutOut comprises a vacuum-based fuseCutOut 40 as described in any of the examples above. The device also comprises a first electrical connector 20 connected to the first electrical connection rod 230 of the vacuum-based fuseCutOut; a second electrical connector 50 connected to the second electrical connection rod 210 of the vacuum-based fuseCutOut; and at least one insulation structure 10, 30 surrounds at least part of the first electrical connector 20.

[0042] The new vacuum-based fuseCutOut is described in specific detail below, where again reference is made to FIGS. 1-2.

[0043] The vacuum-based fuseCutOut in accordance with the disclosure is a one-time use vacuum device, which has two current carrying terminals inside the vacuum environment inside the vacuum device. The new vacuum-based fuseCutOut has the function of a fuse CutOut and will be very similar in the function to an expulsion fuse CutOut.

[0044] The new vacuum-based fuseCutOut has the following functionally. The fuse wire will short circuit both installed contacts used in the vacuum device. In case of fuse current interruption, the wire between both the contacts will melt when a threshold current is reached, and a spark or arc will occur between both the contacts and will be interrupted or quenched as well. In the case of overcurrent interruption functionality, the full-range function is given because due to the vacuum insulation around the wire the fuse-wire will melt a bit above the rated fuse current and the full range characteristic will be achieved. At short circuit current conditions, the fuse-wire instantly melts and the short circuit current is established/ignited and a vacuum arc is created. This arc is however steered, like in today's vacuum interrupter technology, between both contacts and finally be interrupted at current zero. The arc will be kept inside the vacuum device, and after interruption the part (fuse wire) can be completely exchanged/replaced like the solutions we have today in current limiting fuse. On one side of the device an elastic lid or a bellows is provided, which allows a movement of a pin to get a striker function: After the interruption of the fuse, a CutOut automatically drops out to show it's visible cut off operation and showing a separation/insulation distance. The new technique provides a vacuum device, which has two transverse magnetic field. (TMF)Butt, axial magnetic field (AMF) or hybrid (TMF-AMF) contacts with a fixed contact gap between the contact pair.

[0045] A fuse wire is installed between the 2?TMF contacts and/or on the electrical rods to which the contacts are mounted to let the current flow through the device. The wire is installed freely in the vacuum atmosphere or can be covered to achieve specific melting characteristics (known from standard fuse technology).

[0046] Furthermore, a steel wire can be placed in addition to the fuse-wire to provide mechanical support from top side in situation when a spring force on the striker side is utilized to release mechanical energy on CutOut mechanism that aids in keeping the contacts at a fixed separation until the fuse-wire melts. The main advantage is the comparable low cost of such a technology, with the providing of a green and safe interruption, with no sparking and no gas or plasma release to the environment. Furthermore, the noise while interruption is quite limited and silent.

[0047] Because of the superior dielectric behaviour of the interruption device, the part as such can be small. The dielectrically performance in air (or the surrounding atmosphere) is being provided by an insulation material, like silicone or other outdoor material. To have a corrosion protection and UVlight resistance this material can be applied to elongate the creepage length and to avoid flashover along the interruption device at the time of load or short circuit interruption.

[0048] FIG. 1 shows an outer view of the new vacuum-based fuseCutOut device coated with embedding material, and FIG. 2 shows a cross section of the vacuum-based fuseCutOut.

[0049] The vacuum-based fuseCutOut allows the required fuse functionality purely based on the melting of the fuse wire 220. The fuse wire can be inserted as shown in FIG. 1 and elongated in length by providing a hollow structure inside the contact and connection part, not shown here.

[0050] Both shown contact parts 110 and 130 are used in case a short circuit interruption current must be done. Rated current interruption is possible even with only Butt-contacts. Due to the vacuum technology a high transient recovery voltage (TRV) can be accommodated, without the risk of failing current interruption at current zero. This means that the different required TRV values in the markets around the world can be met with the same new fuse.

[0051] In the situation when interruption is required, the fuse-wire 220 will melts with a foreseeable melting characteristic. The rated- and short circuit current interruption is done in the gap distance between the contact 100 and 130. Only a slight movement of the so-called movable side (the contact 130 and/or the electrical connection rod 210) is needed to get the striker functionality to release the drop-out function of the fuse CutOut in case that will be needed. The fuse-wire can be supported by a steel wire which is installed in parallel to the fuse-wire 220 to keep the mechanically pre-loaded spring 180 in position and provide the potential energy to get the striker moving functionality.

[0052] To get a certain movement for the striker a movement inside the vacuum fuse 40 is facilitated using a membrane or a simple bellows 150; only one single operation is needed. The insulation and to keep the vacuum device sealed is given by the insulation part 120, to insulate for example the support lid 140 and the electrical connection rod 230 in case of current interruption.

[0053] An outer insulation can be achieved by an over moulding of the device using silicone 10 for example, as shown FIG. 1. This provides the needed insulation distance to take the voltage while current interruption and providing corrosion protection as well. On or more parts, and indeed the full CutOut vacuum device 40, can be covered with the insulation material.

[0054] In summary the following advantages are provided by the new vacuum-based fuseCutOut: Spark-free and a so-called green current interruption technology; Low cost for the device based on the well-developed vacuum technology; Use of known TMF/AMF or hybrid contact(s); Less type testing required based on vacuum technology steep TRV requirements will be taken easily.

[0055] The number of required variants can be limited because the TRV needs can be covered based on the vacuum technology via smaller number of variants. Specific high short circuit interruption performanceless volume neededdimensions comparable low. Dimensions can fit to today's CutOut holder and mechanism and the electrical insulation for each rating, and can be smaller than today's technology.

LIST OF REFERENCE NUMERALS

[0056] 10 Outer insulation material or surrounding insulation [0057] 20 Electrical connection rod, or connector, one side of connection to the CutOut current connection circuit [0058] 30 Insulation structures with creepage ribs [0059] 40 Vacuum-based fuseCutOut in the current loop [0060] 50 Electrical connection rod, or connector, the side with striker to release the CutOut mechanism to get drop out functionality [0061] 100 Contact disc TMF type (as one possibility), fixed side [0062] 110 Outer insulation material or surrounding insulation, shown silicone coated/embedded [0063] 120 Vacuum ceramic cylinder/insulation device [0064] 130 Contact disc TMF type, slightly moving side to get striker functionality to release dropout function, (drop out function as per today's technology) [0065] 140 Support and lid part of vacuum device [0066] 150 Flexible elements to allow limited movement, striker function (shown bellows) but can be also an elastic membrane [0067] 160 Support lid to cover the components [0068] 170 Bellows connection part or membrane to allow movement for striker functionality [0069] 180 Release spring to operate striker after current interruption [0070] 190 Connection part to support/fixation of the release spring [0071] 200 Electrical connection rod with movement to allow striking function [0072] 210 Electrical connection rod made of copper or another conductive material [0073] 220 Fuse wire/and if needed in addition steel wire [0074] 230 Electrical connection rod

[0075] In an example, when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the vacuum-based fuseCutOut is configured to move the second contact away from the first contact.

[0076] In an example, when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the vacuum-based fuseCutOut is configured to move the second electrical connection rod away from the first electrical connection rod.

[0077] In an example, the second contact is fixedly mounted to the second electrical connection rod.

[0078] In an example, the vacuum-based fuseCutOut comprises a release spring, and when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod the release spring is configured to move the second contact away from the first contact.

[0079] In an example, the first contact is a transverse magnetic field, TMF, contact, and the second contact is a TMF contact.

[0080] In an example, the first contact is an axial magnetic field, AMF, contact, and the second contact is an AMF contact.

[0081] In an example, the first contact is a transverse magnetic field, TMF, contact, and the second contact is an AMF contact.

[0082] In an example, the first contact is an AMF contact, and the second contact is a TMF contact.

[0083] In an example, the first contact is a hybrid contact with the known technology of AMF/TMF or TMF/AMF combination.

[0084] In an example, the vacuum-based fuseCutOut comprises a steel wire, and wherein when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the first contact is held the fixed distance from the second contact at least in part by the steel wire.

[0085] In an example, when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut the first contact is held the fixed distance from the second contact at least in part by the fuse wire.

[0086] In an example, the vacuum-based fuseCutOut comprises an outer body, and wherein the outer body is configured to maintain a vacuum within the body when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut.

[0087] In an example, the vacuum-based fuseCutOut comprises an insulation part located within the outer body, and the insulation part surrounds the first contact and the second contact when the current below the threshold levels flows through the vacuum-based fuseCutOut or no current flows through the vacuum-based fuseCutOut.

[0088] In an example, the insulation part surrounds the first contact and the second contact during movement of the second contact away from the first contact when the fuse wire electrically disconnects the first electrical connection rod from the second electrical connection rod.

[0089] In a second aspect, there is provided a vacuum interrupter device, comprising: a vacuum-based fuseCutOut according to the first aspect; a first electrical connector connected to the first electrical connection rod of the vacuum-based fuseCutOut; a second electrical connector connected to the second electrical connection rod of the vacuum-based fuseCutOut; and at least one insulation structure surrounds at least part of the first electrical connector.

[0090] The above aspects and examples will become apparent from and be elucidated with reference to the embodiments described hereinafter.

[0091] All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

[0092] The use of the terms a and an and the and at least one and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term at least one followed by a list of one or more items (for example, at least one of A and B) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B), unless otherwise indicated herein or clearly contradicted by context. The terms comprising, having, including, and containing are to be construed as open-ended terms (i.e., meaning including, but not limited to,) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., such as) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0093] Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.