Method and shielding arrangement for shielding connection portion of cable at power converter comprising frame or bracket, and power converter

Abstract

A method and a shielding arrangement (100) for shielding a connection portion of a cable (10) at a power converter (200) comprising a frame or bracket (19). The method comprises obtaining (310) an electrically conductive mesh member (12), arranging (320) the electrically conductive mesh member (12) around and along a cable gland (13) on the connection portion and the cable, thereby forming a mesh tube around the connection portion and the cable gland (13), and clamping (330) the electrically conductive mesh member (12) in a first position along a connection portion between the first clamp (14) and the cable (10) and in a second position along a connection portion between the second clamp (20) and the cable gland (13), wherein the electrically conductive mesh member (12) is connected to the frame or bracket (19) via at least one of the first clamp (14) and the second clamp (20). A power converter (200) is also disclosed.

Description

Technical Field

[0001] The present invention generally relates to methods and devices for shielding cables. However, particularly but not exclusively, the present invention relates to shielding the connection portions of cables at power converters such as frequency converters, inverters or rectifiers. Background Art

[0002] Solutions for providing shielding for cables are known to be developed. It is well known that a cable itself may include a shielding cover as a common conductive layer around its conductors for electromagnetic shielding / interference (EMC / EMI). This shielding cover may then be connected to a ground potential, such as at the power converter to which it is connected. However, at the connection portion of the cable for connection to the power converter, the shielding cover is stripped from around the conductors, thus exposing the connection portion to potential electromagnetic compatibility (EMC / EMI) related interference. Therefore, there is still a need to develop shielding solutions for use at electrical equipment. Summary of the Invention

[0003] An object of the present invention is to provide a method and a shielding arrangement for shielding the connection portion of a cable at a power converter including a frame or a bracket and the power converter such as a frequency converter, an inverter or a rectifier. Another object of the present invention is that the method and the shielding arrangement make it easier to provide or upgrade shielding for the power converter, such as EMI / EMC shielding.

[0004] The object of the present invention is achieved by a method and a shielding arrangement for shielding the connection portion of a cable at a power converter including a frame or a bracket and the power converter such as a frequency converter, an inverter or a rectifier as defined in the corresponding independent claims.

[0005] According to a first aspect, there is provided a method for shielding the connection portion of a cable at a power converter including a frame or a bracket. The method includes: holding a conductive mesh member and arranging the conductive mesh member around and along the connection portion and a cable gland on the cable, so as to form a mesh tube around the connection portion and the cable gland. The method further includes: clamping the conductive mesh member at a first position along the connection portion between the first clamp and the cable and at a second position along the connection portion between the second clamp and the cable gland, wherein the conductive mesh member is connected to the frame or the bracket via at least one of the first clamp and the second clamp.

[0006] The method may further include arranging the cable to pass through the cable gland such that the connection portion is on one side of the cable gland while the remaining portion of the cable is on the opposite side of the cable gland.

[0007] In addition, both the first clamp and the second clamp may be coupled to the frame or the bracket.

[0008] The cable gland can be a cable grommet attached to a frame or bracket, such as a rubber or silicone cable grommet. Accordingly, the method can include attaching the cable grommet to the frame or bracket.

[0009] The first position can be closer to the cable end of the connection portion than the second position. The term "cable end" refers to the portion of the connection portion having (a plurality of) exposed conductors for connection to (a plurality of) connectors (such as the (a plurality of) connectors of a power converter).

[0010] The electrically conductive mesh member can be tubular. Accordingly, the method can include arranging the connection portion through the tubular electrically conductive mesh member before connecting the cable to one or more connectors of the power converter.

[0011] The method can include winding the electrically conductive mesh member around and along the connection portion, for example, if the electrically conductive mesh member is planar, at least after being straightened, i.e., before clamping the electrically conductive mesh member with the first clamp and the second clamp. The winding should be such that multiple portions of the electrically conductive mesh member overlap so as to completely enclose the cable in its transverse direction.

[0012] There can be a clamping arrangement including a first clamp and a screw for fastening the clamp portion to the cable, the clamping arrangement being configured for a cable sheath of the cable within a wide diameter range, such that the cable sheath can still be tightened by the clamping arrangement within the wide diameter range.

[0013] According to a second aspect, there is provided a shielding arrangement for a connection portion of a cable at a power converter, the power converter including a frame or bracket. The shielding arrangement includes an electrically conductive mesh member for arranging around and along the connection portion and a cable gland on the cable to form a mesh tube around the connection portion and the cable gland. The shielding arrangement further includes a first clamp and a second clamp, the first clamp being for clamping the electrically conductive mesh member at a first position along the connection portion between the first clamp and the cable, and the second clamp being for clamping the electrically conductive mesh member at a second position along the connection portion between the second clamp and the cable gland. The electrically conductive mesh member is connected to the frame or bracket via at least one of the first clamp and the second clamp.

[0014] Both the first clamp and the second clamp can be coupled to or at least coupleable to the frame or bracket.

[0015] The cable gland can be a cable grommet attached to a frame or bracket, such as a rubber or silicone cable grommet.

[0016] The first position can be closer to the cable end of the connection portion than the second position.

[0017] The electrically conductive mesh member can be tubular. Accordingly, the method can include arranging the connection portion through the tubular electrically conductive mesh member before connecting the cable to one or more connectors of the power converter.

[0018] For example, if the electrically conductive mesh member is planar, then at least after straightening, the electrically conductive mesh member can be wound around and along the connection portion.

[0019] According to a third aspect, there is provided a power converter. The power converter includes: a frame or support, a plurality of switching devices for converting one or more currents and / or voltages, one or more connectors for the cable, and a shielding arrangement according to the second aspect.

[0020] Optionally, the power converter includes a cable gland as a strain relief, such as a rubber or silicone strain relief.

[0021] The present invention provides a method and a shielding arrangement for shielding a connection portion of a cable at a power converter including a frame or support, and a power converter. The present invention provides advantages over known solutions because it provides 360-degree shielding for the connection portion of the cable at the power converter. Since a single electrically conductive mesh member is sufficient to provide the shielding, the cost is very low. In addition, the electrically conductive mesh member can be easily used for new devices or for upgrading existing devices.

[0022] Based on the following detailed description, various other advantages will be apparent to those skilled in the art.

[0023] Herein, the phrase "the number of..." can refer to any positive integer starting from one (1).

[0024] The phrase "a plurality of" can respectively refer to any positive integer starting from two (2).

[0025] Terms such as "first" and "second" are used herein to distinguish one element from another and are not intended to give them a particular precedence or order unless otherwise expressly stated.

[0026] The exemplary embodiments of the present invention presented herein should not be construed as limiting the applicability of the appended claims. The verb "comprising" is used herein as an open limitation and does not exclude the presence of all unrecited features. Unless otherwise expressly stated, the features recited in the appended patent claims can be freely combined with one another.

[0027] The novel features considered to be characteristic of the invention are particularly set forth in the appended claims. However, the invention itself, as well as its construction and method of operation, together with additional objects and advantages thereof, will best be understood from the following description of specific embodiments when read in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Some embodiments of the present invention are shown by way of example and not limitation in the accompanying drawings.

[0029] Figures 1 - 6 A shielding arrangement is schematically shown.

[0030] Figure 7 A conductive mesh member is shown.

[0031] Figure 8 A flowchart of a method is shown.

[0032] Figures 9A - 9C A power converter is schematically shown. Detailed Description

[0033] Figures 1 - 6 A shielding arrangement 100 is schematically shown. The shielding arrangement 100 is for a connection portion of a cable 10 at a power converter including a frame or bracket 19. The connection portion means that some layers of a part of the cable 10 are stripped, if necessary, to expose the conductor. The frame or bracket 19 is preferably located at or connected to the ground potential of the power converter and / or the housing, and / or the electrical ground or land on the grid side.

[0034] The shielding arrangement 100 includes a conductive mesh member 12 arranged to surround and along the connection portion and a cable gland 13 on the cable 10 to form a mesh tube around the connection portion and the cable gland 13. The shielding arrangement 100 further includes a first clamp 14 and a second clamp 20. The first clamp 14 is for clamping the conductive mesh member 12 at a first position along the connection portion between the first clamp and the cable 10 (such as its cable sheath 10A), and the second clamp 20 is for clamping the conductive mesh member 12 at a second position along the connection portion between the second clamp 20 and the cable gland 13. In addition, the conductive mesh member 12 is connected to the frame or bracket 19 via at least one of the first clamp 14 and the second clamp 20.

[0035] Optionally, the length of the conductive mesh member 12 (i.e., the dimension in the longitudinal direction of the cable 10 around which the conductive mesh member 12 is arranged or will be arranged) is at least 3 cm, preferably in the range of 5 - 35 cm, more preferably in the range of 10 - 25 cm, for example about 20 cm.

[0036] The distance between the first clamp 14 and the second clamp 20 can be, for example, in the range of 2 - 30 cm.

[0037] In some cases, both the first clamp 14 and the second clamp 20 are coupled or can be coupled to the frame or bracket 19.

[0038] In addition, the cable gland can be a cable grommet attached to the frame or bracket 19, such as a rubber or silicone cable grommet or a cable grommet of other electrically insulating materials.

[0039] The first position can be closer to the cable end of the connection portion than the second position, as Figures 1 - 5 shown, with the first clamp 14 above the second clamp 20 shown in the figure.

[0040] In some examples, the electrically conductive mesh member 12 is tubular. Thus, it forms a mesh tube that can be arranged around the connection portion and the cable gland 13. Therefore, before connecting the cable to one or more connectors of the power converter, the cable 10 or at least its connection portion may need to be arranged through the tubular electrically conductive mesh member 12.

[0041] In alternative examples, the electrically conductive mesh member 12 can be planar at least after being straightened. Thus, the electrically conductive mesh member 12 can be wound around and along the connection portion.

[0042] In addition, Figures 1 - 6 shown with respect to the frame or bracket 19, which can include two plate-like portions connected to the bracket link 19A. A base plate 22 having an opening for arranging the cable 10 passing through it can be included in the frame or bracket 19.

[0043] In addition, the first clamp 14 can include a first clamp portion, such as having a U shape, which can be attached to the frame or bracket 19 from the ends of the U shape (it can also have other shapes, such as V shape or C shape or more complex shapes). Figure 4 Shown from the side opposite to Figure 1 the shielding arrangement 100, the clamp attachment portion 14A or the clamp lock is shown, such as including openings to which the first clamp portion can be attached. In addition, the first clamp 14 can also include a second clamp portion 16, which can be tightened by a screw 15 having a shaft 17, such as tightened against the thread 18 of the clamp 14, or tightened to the cable 10 through a similar adjustment mechanism, so as to clamp the electrically conductive mesh member 12 between them in the first position. Therefore, the first clamp 14 can include multiple parts and an adjustment mechanism. The clamping arrangement of the clamp 14, the screw 15, and the clamp portion 16 ensures a wide range of diameters of the cable sheath 10A, which can be tightened by the clamping arrangement.

[0044] Therefore, in some embodiments, preferably a clamping arrangement is configured for the cable sheath 10A of the cable 10 within a wide diameter range, which can include the first clamp 14, a screw 15 for fastening the clamp portion 16 to the cable 10, such that the electrically conductive mesh member 12 is arranged between them, and this clamping arrangement can fasten the cable sheath 10A within a wide diameter range.

[0045] Regarding the second clamp 20, according to some embodiments, it may be a plate-like clamp that can be arranged on the bottom portion of the cable gland 13, thereby pressing the conductive mesh member 12 against the cable gland 13, as Figures 1 - 5 clearly visible. The fastening means, such as screws, bolts or clips, etc., marked with reference numeral 21 are used to lock the second clamp 20 in its position to clamp the conductive mesh member 12 on the cable gland 13.

[0046] Figure 6 The cable sheath 10A of the cable 10 is shown. In addition, Figure 6 it is shown how the first clamp 14 has a portion extending through the opening in the frame or bracket 19.

[0047] Figure 7 The conductive mesh member 12 is shown, preferably a wire mesh. The conductive mesh member 12 is as Figure 7 shown, in the form of a mesh roll, and the member 12 can be cut from the mesh roll to show a suitable size. The material of the conductive mesh member 12. Figure 7 The mesh roll in it includes a tubular mesh or a planar mesh. The material of the conductive mesh member 12 can be (stainless) steel. However, alternatively, it can be some other conductive materials, such as copper, silver, aluminum or some metal alloys. The length of the conductive (wire) mesh member 12 can be as described above.

[0048] Figure 8 A flowchart of a method is shown.

[0049] Item or step 300 refers to the starting phase of the method. Suitable equipment and components can be obtained and the system can be assembled.

[0050] Item or step 310 involves obtaining the conductive mesh member 12.

[0051] Item or step 320 refers to arranging the conductive mesh member 12 around and along the connecting portion and the cable gland 13 on the cable 10, thereby forming a mesh tube around the connecting portion and the cable gland 13.

[0052] Item or step 330 refers to clamping the conductive mesh member 12 at a first position along the connecting portion between the first clamp 14 and the cable 10, such as its cable sheath 10A, and at a second position along the connecting portion between the second clamp 20 and the cable gland 13, wherein the conductive mesh member 12 is connected to the frame or bracket 19 by at least one of the first clamp 14 and the second clamp 20.

[0053] The method execution can stop at item or step 399.

[0054] The method may further include arranging the cable 10 to pass through a cable gland 13 such that the connection portion is on one side of the cable gland 13 and the remainder of the cable 10 is on the opposite side of the cable gland 13.

[0055] In addition, both the first clamp 14 and the second clamp 20 may be coupled to a frame or support 19.

[0056] The cable gland 13 may be a grommet attached to the frame or support 19, such as a rubber or silicone grommet. Thus, the method may include attaching the grommet to the frame or support 19.

[0057] The first position may be closer to the cable end of the connection portion than the second position.

[0058] The electrically conductive mesh member 12 may be tubular. Thus, the method may include arranging the connection portion through the tubular electrically conductive mesh member 12 before connecting the cable to one or more connectors of the power converter.

[0059] The method may further include winding the electrically conductive mesh member 12 around and along the connection portion, for example, at least after straightening if the electrically conductive mesh member is planar.

[0060] Figures 9A - 9C A power converter 200 is schematically illustrated. The power converter 200 may be, for example, a frequency converter as Figure 9A schematically illustrated, an inverter as Figure 9B shown, or a rectifier as Figure 9C shown. The power converter 200 preferably includes one or more connectors 210 for connecting the cable 10. The power converter 200 may be, for example, a single-phase or three-phase converter device 200, as Figures 9A - 9C shown.

[0061] As will be understood by those skilled in the art, the power converter 200 may include various components not shown herein but will be described in detail. For example, the power converter 200 may include a controller and various sensors for measuring the (plural) current and (plural) voltage to control the operation of the device 200.

[0062] The power converter 200 includes a frame or support 19, a plurality of switching devices for converting one or more currents and / or voltages ( Figures 9A - 9C not shown, however, as is known to those skilled in the art, it is included in the AC / DC or DC / AC symbol) and one or more connectors 210 for the cable 10. In addition, as described above, the power converter 200 further includes a shielding arrangement 100 or any of its embodiments.

[0063] In various embodiments, the power converter 200 includes a cable gland 13, which is a grommet such as rubber or silicone and is attached, for example, to a frame or bracket 19.

Claims

1. A method for shielding a connection portion of an electrical cable (10) at a power converter (200) comprising a frame or bracket (19), wherein the method comprises: obtaining (310) a conductive mesh member (12), Arranging (320) the conductive mesh member (12) around and along the connecting portion and the cable gland (13) on the cable, thereby forming a mesh tube around the connecting portion and the cable gland (13), and The conductive mesh member (12) is clamped (330) at a first position along the connection between a first clamp (14) and the cable (10) and at a second position along the connection between a second clamp (20) and the cable gland (13), wherein the conductive mesh member (12) is connected to the frame or bracket (19) via at least one of the first clamp (14) and the second clamp (20).

2. The method of claim 1, comprising arranging the cable (10) through the cable gland (13) so that the connection portion is located on one side of the cable gland (13) and the remainder of the cable (10) is located on the opposite side of the cable gland (13).

3. The method of claim 1 or 2, wherein the first clamp (14) and the second clamp (20) are both coupled to the frame or bracket (19).

4. The method according to any one of claims 1-3, wherein the cable gland (13) is a grommet attached to the frame or bracket (19).

5. The method of any one of claims 1-4, wherein the first position is closer to a cable end of the connecting portion than the second position.

6. The method according to any one of claims 1 to 5, wherein the conductive mesh member (12) is tubular.

7. The method according to any one of claims 1 to 5, comprising winding the conductive mesh member (12) around and along the connecting portion.

8. The method according to any one of claims 1 to 7, wherein: A clamping arrangement comprising the first clamp (14), a screw (15) for fastening a clamp part (16) to the cable (10), is configured for a cable jacket (10A) of the cable (10) over a wide diameter range, such that the cable jacket (10A) can be fastened by the clamping arrangement.

9. A shielding arrangement (100) for a connection portion of a cable (10) at a power converter (200), the power converter comprising a frame or a support (19), wherein the shielding arrangement (100) comprises: a conductive mesh member (12) arranged around and along the connecting portion and the cable gland (13) on the cable (12) to form a mesh tube surrounding the connecting portion and the cable gland (13); a first clamp (14) for clamping the conductive mesh member (12) at a first position along the connection portion between the first clamp (4) and the cable (10), and a second clamp (20), the second clamp being used to clamp the conductive mesh member (12) at a second position along the connection portion between the second clamp (20) and the cable gland (13), The conductive mesh member (12) is connected to the frame or bracket (19) via at least one of the first clamp (14) and the second clamp (20).

10. The shielding arrangement (100) of claim 9, wherein the first clamp and the second clamp are both coupled or coupleable to the frame or bracket.

11. The shielding arrangement (100) of claim 9 or 10, wherein the cable gland is a grommet attached to the frame or support.

12. The shielding arrangement (100) of any one of claims 9-11, wherein the first position is closer to a cable end of the connecting portion than the second position.

13. The shielding arrangement (100) of any one of claims 9-12, wherein the conductive mesh member (12) is tubular.

14. The shielding arrangement (100) of any one of claims 9-13, wherein the conductive mesh member (12) is planar.

15. A power converter (200), comprising: Frame or bracket (19), a plurality of switching devices for converting one or more currents and / or voltages, one or more connectors (210) for the cable (10), and A shielding arrangement (100) according to any one of claims 8 to 13.

16. The power converter (200) of claim 15, comprising a cable gland (13) as a grommet.

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