SE2050904A1 - Manufacturing of electrical conductors - Google Patents

Abstract

Provided is a method for manufacturing a conductor comprising the steps of choosing a desired dimension D of the conductor, determining a first percentage P1 and a second percentage P2 of a respective first and second component of the conductor and assembling the first and second components corresponding to the determined first and second percentages into a conductor having the chosen dimension D, characterized in that that determining the first percentage P1 and second percentage P2 comprises making two consecutive calculations according to a first and a second formulation: P1 = 12.20 - D * 12.20/75, P2 = 100 - P1.

Description

MANUFACTURING OF ELECTRICAL CONDUCTORS Technical field 1. 1. id="p-1" id="p-1"

[0001] The present invention relates generally to electrical conductors and cables.More specifically, it relates to methods for manufacturing conductors and cables that radiate a low electromagnetic field.

Background art 2. 2. id="p-2" id="p-2"

[0002] Electrical conductors come in many different forms. Typically, it is theintended use of the conductor that determines the design of an electrical conductor.Some conductors are designed for power distribution, others are designed fortransmission of signals such as telecommunications signals as well as for otherpurposes. Furthermore, electrical conductors can be manufactured from wires ofdifferent materials such as copper, aluminum, steel or nickel. Typically, two or moreconductors are joined to form a cable. 3. 3. id="p-3" id="p-3"

[0003] An electrical current running through a conductor causes it to radiate anelectromagnetic field. This electromagnetic field can negatively affect equipment orother conductors in the proximity of the conductor, which can limit for example howclosely together conductors or cables can be arranged. Therefore, regardless of thetype of conductor, it is typically desired that the radiated electromagnetic field is low.Often, this is achieved by providing shielding components which surround the entire length of the conductor. 4. 4. id="p-4" id="p-4"

[0004] An alternative to providing shielding components is disclosed in US Patent9,953,737. The patent discloses a conductor and a cable having an aluminum coresurrounded by copper wires which has the effect of reducing the electromagneticfield. . . id="p-5" id="p-5"

[0005] Commonly, standardized dimensions of electrical conductors are used. Butwith the fast evolution of technology, conductors may need completely differentdimensions, than those that are industry standard today. lt remains to be solved howto obtain a conductor emitting a low electromagnetic field at any given dimension ofthe conductor. 6. 6. id="p-6" id="p-6"

[0006] Therefore, there is still a need for a method for providing an electricalconductor which displays a reduction of the electromagnetic field to a desired level at any given dimension of the conductor.

Summary of invention 7. 7. id="p-7" id="p-7"

[0007] lt is an object of the invention to address at least some of the problemsand issues outlined above. lt is possible to achieve these objects and others byproviding a method for manufacturing an electrical conductor and a method formanufacturing a cable comprising such conductors, which display a desired reductionof the electromagnetic field at any given dimension of the conductor according to the present invention. 8. 8. id="p-8" id="p-8"

[0008] The invention is based on the insight, that the electromagnetic field can bereduced to a desired amount for a given dimension of a conductor when a relationbetween cross-sectional areas of aluminum and copper is a relation specified for thatgiven dimension. When reference is made to the dimension of the conductor, itshould be understood as the cross-sectional area of the conductor, which isessentially equal throughout the length of the conductor. 9. 9. id="p-9" id="p-9"

[0009] According to the invention, there is provided a method for manufacturing aconductor comprising the steps of choosing a desired dimension D of the conductor,determining a first percentage P1 and a second percentage P2 of a respective firstand second component of the conductor and assembling the first and secondcomponents corresponding to the determined first and second percentages into aconductor having the chosen dimension D, characterized in that that determining thefirst percentage P1 and second percentage P2 comprises making two consecutivecalculations according to a first and a second formulation: P1 = 12.20 - D * 1220/75,P2 = 100 - P1. . . id="p-10" id="p-10"

[0010] The technical effect provided by a method according to the invention is thatthe percentage of each component can be calculated based on a desired dimensionof the manufactured conductor. Having a combination of a certain dimension with itscorresponding calculated percentages of each component, causes the manufacturedconductor to emit a reduced electromagnetic field, compared to having otherpercentages of each component combined with that desired dimension. 11. 11. id="p-11" id="p-11"

[0011] ln an exemplary embodiment of the invention, the first component is aluminum wire and the second component is copper wire. 12. 12. id="p-12" id="p-12"

[0012] ln an exemplary embodiment of the invention, the first percentage and thesecond percentage are percentages of the cross-sectional area of the conductor. 13. 13. id="p-13" id="p-13"

[0013] ln an exemplary embodiment of the invention, wherein the dimension Dcorresponds to the cross-sectional area of the conductor. 14. 14. id="p-14" id="p-14"

[0014] ln an exemplary embodiment of the invention, the first component is one single aluminum wire and second component is a plurality of copper wires. . . id="p-15" id="p-15"

[0015] ln an exemplary embodiment of the invention, the aluminum wire is a central wire surrounded by the plurality of copper wires. 16. 16. id="p-16" id="p-16"

[0016] ln an exemplary embodiment of the invention, the first and secondpercentages include a tolerance of 101%. 17. 17. id="p-17" id="p-17"

[0017] According to the invention, there is also provided a method formanufacturing a cable comprising the steps of providing at least one conductormanufactured according to any of the exemplary embodiments, providing the at leastone conductor with at least one of a jacket, a filling material, a binder and a coating. 18. 18. id="p-18" id="p-18"

[0018] According to the invention, there is also provided a conductor manufacturedaccording to the exemplary embodiments. 19. 19. id="p-19" id="p-19"

[0019] According to the invention, there is also provided a cable manufacturedaccording to the exemplary embodiments.

Brief description of drawinqs . . id="p-20" id="p-20"

[0020] The invention is now described, by way of example, with reference to theaccompanying drawings, in which: Fig. 1 shows a conductor comprised by aluminum and copper wires.Fig. 2 shows a cable with two conductors.

Fig. 3 shows a cable with one conductor.

Description of embodiments 21. 21. id="p-21" id="p-21"

[0021] ln the following, a detailed description of a method for manufacturing aconductor and cable is disclosed. ln Fig 1, a cross-sectional view of an electrical conductor 1 in accordance with a firstembodiment is shown. A conductor is defined as an assembly of a plurality ofconducting wires, and a wire is defined as a single conducting metal thread. Theelectrical conductor1 has a central core comprising an aluminum wire 11.Surrounding the central core comprising the aluminum wire 11, one or more copperwires 12 are provided. Further, the electrical conductor 1 has a dimension D whichcan be any desired dimension that is suitable for the intended use of the conductor.The dimension D corresponds to the cross-sectional area of the conductor, which inturn is given by the sum of the cross-sectional areas of the aluminum wire 11 and thecopper wires 12. Surprisingly, it has been found that the magnitude of theelectromagnetic field radiated from the electrical conductor 1 depends on what areapercentage of the dimension D comprises the aluminum wire 11 and what areapercentage comprises the copper wires 12. Furthermore, it has been found that it ispossible to achieve a greater reduction of the electromagnetic field from theconductor 1 using certain relations between the area percentages of aluminum wire11 and copper wires 12, compared to others. Even more surprisingly, it has beenfound that for a given dimension D there are corresponding relations between thearea percentages which most sufficiently reduce the electromagnetic field for that given dimension.

A first and a second formulation are therefore provided which allow a first and asecond cross-sectional area percentage to be calculated. The first percentagecorresponds to the area of the aluminum wire 11 and the second percentagecorresponds to the sum of the areas of the copper wires 12. For a given dimension,the first and second formulations can be used to calculate a first and a second areapercentage which to a desired extent reduces the electromagnetic field radiated from the electrical conductor 1 having that given dimension.

Since the electrical conductor 1 only comprises the aluminum wire 11 and copperwires 12, the first and second area percentages have a sum equal to 100%.

Naturally, for a given length of the conductor, the area percentages also representthe volume percentages of the aluminum wire 11 and the copper wires 12.

The first formulation results in the first percentage, PAi, namely the area percentageof aluminum wire 11. lt is calculated by firstly determining a desired dimension D forthe conductor 1 and subsequently making a calculation according to the firstformulation: PA] = 12.20 - (D »f 12.20 10.75 100 22. 22. id="p-22" id="p-22"

[0022]The second formulation results in the second percentage, Pcu, namely thearea percentage of the copper wires 12. This is the remaining area of thedimension D up to 100%, and is thus obtained by subtracting the first percentagefrom 100%: PCu:100_PAl. 23. 23. id="p-23" id="p-23"

[0023] Following are some examples where the first and second formulations areemployed. The examples should not be seen as limiting to the scope of the invenfion.

Example 1: D = 1.0 mm2 24. 24. id="p-24" id="p-24"

[0024] An electrical conductor 1 with a dimension D of 1 mm2 is desired.Furthermore, a low electromagnetic field radiated from the electrical conductor 1 isdesired. ln order to reduce the electromagnetic field to a desired extent, a relationbetween the cross-sectional area percentage of the aluminum wire 11 and thecopper wires 12 is sought. The percentage of the aluminum wire 11 is calculatedthrough the first formulation: 12.20 * I 0.75 100 . . id="p-25" id="p-25"

[0025] PA, = 12.20 - (1 ȧ 26. 26. id="p-26" id="p-26"

[0026] The obtained percentage 12.04 % aluminum. The remaining area of thedimension D is calculated through the second formulation: 27. 27. id="p-27" id="p-27"

[0027] Pcu = 100 - 12.04 = 87.96 28. 28. id="p-28" id="p-28"

[0028] The obtained percentage is 87.96 % copper. 29. 29. id="p-29" id="p-29"

[0029] The relation is thus 12.04 % of the aluminum wire 11 and 87.96 % of the copper wires 12.

Example 2: D = 2.5 mm2 . . id="p-30" id="p-30"

[0030] An electrical conductor 1 with a dimension D of 2.5 mm2 is desired.Furthermore, a low electromagnetic field radiated from the electrical conductor 1 isdesired. ln order to reduce the electromagnetic field to a desired extent, a relationbetween the cross-sectional area percentage of the aluminum wire 11 and thecopper wires 12 is sought. The percentage of the aluminum wire 11 is calculatedthrough the first formulation: 12.20 * I 0.75 100 31. 31. id="p-31" id="p-31"

[0031] PA] = 12.20 - (2.5 * 32. 32. id="p-32" id="p-32"

[0032] The obtained percentage 11.79 % aluminum. The remaining area of thedimension D is calculated through the second formulation: 33. 33. id="p-33" id="p-33"

[0033] Pcu = 100 - 11.79 = 88.21 34. 34. id="p-34" id="p-34"

[0034] The obtained percentage is 88.21 % copper. . . id="p-35" id="p-35"

[0035] The relation is thus 11.79 % of the aluminum wire 11 and 88.21 % of thecopper wires 12.

Example 3: D = 16.0 mm2 36. 36. id="p-36" id="p-36"

[0036] An electrical conductor 1 with a dimension D of 16 mm2 is desired.Furthermore, a low electromagnetic field radiated from the electrical conductor 1 isdesired. ln order to reduce the electromagnetic field to a desired extent, a relationbetween the cross-sectional area percentage of the aluminum wire 11 and thecopper wires 12 is sought. The percentage of the aluminum wire 11 is calculatedthrough the first formulation: 12.20 * I 0.75 100 [mm] PA] = 12.20 - (16 ȧ 38. 38. id="p-38" id="p-38"

[0038] The obtained percentage is 9.06 % aluminum. The remaining area of thedimension D is calculated through the second formulation: 39. 39. id="p-39" id="p-39"

[0039] Pcu = 100 - 9.06 = 91.40 40. 40. id="p-40" id="p-40"

[0040] The obtained percentage is 91.40 % copper. 41. 41. id="p-41" id="p-41"

[0041] The relation is thus 9.06 % of the aluminum wire 11 and 91.40 % of the copper wires 12.

Manufacturing method 42. 42. id="p-42" id="p-42"

[0042] The invention relates to a method for manufacturing the electricalconductor. The method comprises four steps: 1. Determining a desired dimension D, 2. Making a calculation according to the first formulation, 3. Making a calculation according to the second formulation, 4. Assembling an electrical conductor 1 having the desired dimension D andcomprising the aluminum wire 11 and the copper wires 12 such that the relationbetween the cross-sectional area percentages correspond to those calculated in theprevious steps i 1%, more preferably i 0.5 %, even more preferably 0.1 %. 43. 43. id="p-43" id="p-43"

[0043] The individual wires which are arranged to be assembled into the electricalconductor 1 can be any number and have any cross-sectional area. The appearanceof the individual wires depends on what is suitable to arrive at a conductor havingboth the desired dimension and the corresponding relation between the areapercentages. For example: The aluminum wire 11 and the individual copper wires 12can have different or the same cross-sectional area, the cross-sectional area of thealuminum wire can be larger or smaller than that of the individual copper wires 12,the individual copper wires 12 can each have the same or different cross-sectionalareas, the copper wires 12 can be any amount of wires, the copper wires 12 can be arranged around the aluminum wire 11 in one or a plurality of layers. 44. 44. id="p-44" id="p-44"

[0044] The invention also relates to a method for manufacturing a cable 6comprising one or more of the electrical conductor 1. An exemplary embodiment ofthe cable 6 can be seen in Fig 2. The method of manufacturing the cable 6 comprises providing at least one electrical conductor 1 and providing each of the at least oneelectrical conductor 1 with a jacket 2 of insulation wherein the jacket 2 can be of anytype used for cables and of any suitable material such as a polymer-based material,for example TPS 130. Furthermore, the method comprises providing a filling material3. The filling material 3 can be of any type used in cables and of any suitable materialsuch as a polymer-based material. Surrounding the at least one insulated electricalconductor1 and the filling material 3, a binder 4 is provided. Surrounding the binder 4, an outer coating 5 is provided. 45. 45. id="p-45" id="p-45"

[0045] A possible version of the cable 6, namely the cable 6', can be seen in Fig 3.The cable 6' comprises only one of the electrical conductor 1. The method ofmanufacturing the cable 6' comprises providing one electrical conductor 1 andproviding it with a jacket 2. Surrounding the insulated electrical conductor 1, an outer coating 5 is provided. 46. 46. id="p-46" id="p-46"

[0046] A method of manufacturing an electrical conductor and a method for manufacturing a cable have been shown and described. lt will be realized that theinventive idea is not limited to the embodiments disclosed herein but can be variedwithin the scope of the appended claims without departing from the inventive idea.

Claims (10)

1. A method for manufacturing a conductor (1) comprising the steps of:- choosing a desired dimension D of the conductor (1 ), - determining a first percentage P1 and a second percentage P2 of a respectivefirst (11) and second (12) component of the conductor (1), - assembling the first (11) and second (12) components corresponding to thedetermined first and second percentages into a conductor (1) having the chosen dimension D, c h a ra cte r i z e d in th at determining the first percentage P1 and secondpercentage P2 comprises making two consecutive caicuiations according to a first and a second formulation:P1 = 12.20 - D *12.20/75P2 = 100 - P1.

2. A method according to c|aim 1, wherein the first component is aiuminum wire and the second component is copper wire.

3. A method according to any of the preceding c|aims, wherein the first percentageand the second percentage are percentages of the cross-sectional area of theconductor (1 ).

4. A method according to any of the preceding c|aims, wherein the dimension D corresponds to the cross-sectional area of the conductor (1 ).

5. A method according to any of the preceding c|aims when depending on c|aim 2,wherein the first component is one single aiuminum wire and second component is a p|ura|ity of copper wires.

6. A method according to c|aim 5, wherein the aiuminum wire is a central wire surrounded by the p|ura|ity of copper wires.

7. A method according to any of the preceding claims, wherein the first and secondpercentages include a tolerance of 101%.

8. A method for manufacturing a cable comprising the steps of: - providing at least one conductor (1) manufactured according to any of the preceding claims, - providing the at least one conductor (1) with at least one of a jacket (2), a filling material (3), a binder (4) and a coating (5).

9. A conductor manufactured according to any of the claims 1 - 7.

10.A cable manufactured according to claim 8.