Insulated composite power cable and method of making and using same
An insulated composite power cable having a wire core defining a common longitudinal axis, a multiplicity of composite wires around the wire core, and an insulative sheath surrounding the composite wires. In some embodiments, a first multiplicity of composite wires is helically stranded around the wire core in a first lay direction at a first lay angle defined relative to a center longitudinal axis over a first lay length, and a second multiplicity of composite wires is helically stranded around the first multiplicity of composite wires in the first lay direction at a second lay angle over a second lay length, the relative difference between the first lay angle and the second lay angle being no greater than about 4°. The insulated composite cables may be used for underground or underwater electrical power transmission. Methods of making and using the insulated composite cables are also described.
1. A composite power cable, comprising:
a first composite wire defining a common longitudinal axis;
a plurality of second composite wires helically stranded around the first composite wire about the common longitudinal axis;
an insulative sheath individually surrounding the first composite wire and an insulative sheath individually surrounding each of the second composite wires, wherein the insulative sheaths comprise a thermoplastic polymeric material; and
a first plurality of aluminum or aluminum alloy wires helically stranded around and surrounding the plurality of second composite wires;
wherein the first composite wire and each of the second composite wires comprise a plurality of carbon fibers in a polymeric matrix; and
wherein the insulative sheaths are distinct from the polymeric matrices of the first and second composite wires.
2. The composite power cable of claim 1 , wherein at least a portion of the plurality of second composite wires is arranged around the first composite wire defining the common longitudinal axis in at least one cylindrical layer formed about the common longitudinal axis when viewed in a radial cross section.
3. The composite power cable of claim 1 , wherein the plurality of second composite wires is arranged in at least two cylindrical layers defined about the common longitudinal axis when viewed in a radial cross section.
4. The composite power cable of claim 3 , wherein each cylindrical layer is stranded at a lay angle in a lay direction that is the same as a lay direction for each adjoining cylindrical layer.
5. The composite power cable of claim 4 , wherein a relative difference between lay angles for each adjoining cylindrical layer is greater than 0° and no greater than about 4°.
6. The composite power cable of claim 1 , wherein the composite wires have a cross-sectional shape selected from the group consisting of circular, elliptical, and trapezoidal.
7. The composite power cable of claim 1 , wherein the polymer matrix comprises a (co)polymer selected from the group consisting of an epoxy, an ester, a vinyl ester, a polyimide, a polyester, a cyanate ester, a phenolic resin, a bis-maleimide resin, polyetheretherketone, and combinations thereof.
8. A method of making the composite power cable of claim 1 , comprising:
providing a wire core defining a common longitudinal axis;
arranging a plurality of composite wires around the wire core; and
surrounding the plurality of composite wires with a sheath.
9. The composite power cable of claim 1 , wherein each of the plurality of second composite wires has a diameter of at least 1.0 mm and at most 5 mm.
10. The composite power cable of claim 1 , wherein the first composite wire has a diameter of at least 1.0 mm and less than 5 mm.
11. The composite power cable of claim 1 , wherein the plurality of second composite wires is stranded to have a lay factor of from 10 to 150.
12. The composite power cable of claim 1 , wherein the first composite wire and each of the second composite wires has cross-sectional shape that is generally circular.
13. The composite power cable of claim 1 , wherein the power cable comprises polyetheretherketone.
14. The composite power cable of claim 1 , further comprising a first plurality of aluminum or aluminum alloy wires helically stranded around the plurality of second composite wires.
15. The composite power cable of claim 14 , wherein the first plurality of aluminum or aluminum alloy wires is stranded in a lay direction opposite to that of the plurality of second composite wires.
16. The insulated composite power cable of claim 14 , wherein the first plurality of aluminum or aluminum alloy wires have a cross-sectional shape that is generally circular or trapezoidal.
17. The composite power cable of claim 14 , wherein the first plurality of aluminum or aluminum alloy wires comprises aluminum wires.
18. The composite power cable of claim 17 , wherein the aluminum wires have a tensile breaking strength between 41 MPa and 83 MPa.
19. The composite power cable of claim 17 , wherein the aluminum wires have a tensile breaking strength of at least 138 MPa.
20. The composite power cable of claim 14 , wherein the first plurality of aluminum or aluminum alloy wires comprises aluminum alloy wires.
21. The composite power cable of claim 20 , wherein the aluminum alloy wires comprise aluminum-zirconium alloy wires.
22. The composite power cable of claim 14 , further comprising a second plurality of aluminum or aluminum alloy wires helically stranded around the first plurality of aluminum or aluminum alloy wires.