Electrical transmission cables with composite cores

1. An electrical cable comprising:

(a) a cable core comprising at least one composite core, the composite core comprising:

(i) at least one rod comprising a plurality of consolidated thermoplastic impregnated rovings, the rovings comprising continuous carbon fibers oriented in the longitudinal direction and a thermoplastic matrix that embeds the carbon fibers, the carbon fibers having a ratio of ultimate tensile strength to mass per unit length of greater than about 1,000 MPa/g/m, wherein the thermoplastic matrix comprises a polyphenylene sulfide, and wherein the rod comprises from about 30 wt. % to about 75 wt. % carbon fibers and from about 25 wt. % to about 70 wt. % thermoplastic matrix; and

(ii) a capping layer surrounding the at least one rod, wherein the capping layer comprises a polyether ether ketone and contains less than 5 wt. % of continuous carbon fibers;

wherein the composite core has a flexural modulus of from about 15 to about 200 GPa; and

(b) a plurality of conductive elements surrounding the cable core, wherein the conductive elements comprise aluminum or an aluminum alloy.

2. The cable of claim 1 , further comprising a partial or complete layer of a tape or a coating between the cable core and the plurality of conductive elements.

3. The cable of claim 1 , wherein the cable core comprises two or more composite cores.

4. The cable of claim 1 , wherein the cable core comprises from 2to 37 composite cores.

5. The cable of claim 1 , wherein the cable comprises 7, 19, 26, or 37 conductive elements.

6. The cable of claim 1 , wherein the cable comprises from 2 to about 50 conductive elements.

7. The cable of claim 1 , wherein:

the cable core is a stranded core comprising 7 composite cores; and

the cable comprises 26 conductive elements arranged in 2 layers around the cable core.

8. The cable of claim 7 , wherein the composite cores have a density in a range from about 1.3 g/cc to about 1.7 g/cc.

9. The cable of claim 1 , wherein the cable has:

a 10-year creep value at 15% RBS (rated breaking stress) of less than about 0.2%; and

a 10-year creep value at 30% RBS (rated breaking stress) of less than about 0.25%.

10. The cable of claim 1 , wherein the capping layer has a thickness in a range from about 0.02 mm to about 5 mm and contains less than about 1 wt. % of continuous carbon fibers.

11. The cable of claim 1 , wherein the capping layer contains 0 wt. % of continuous carbon fibers.

12. The cable of claim 1 , wherein the cable has:

a sag, at rated temperature of 180° C., for a 300-meter level span with a NESC light loading, in a range from about 3 m to about 9.5 m; and

a sag, at rated temperature of 180° C., for a 300-meter level span with a NESC heavy loading, in a range from about 3 m to about 7.5 m.

13. The cable of claim 1 , wherein the cable passes an Aeolian vibration test at 100 million cycles.

14. The cable of claim 1 , wherein the capping layer has a thickness in a range from about 0.01 mm to about 10 mm.

15. The cable of claim 1 , wherein the composite core has:

a bending radius in a range from about 1 cm to about 50 cm; and

a void fraction of about 6% or less.

16. The cable of claim 15 , wherein the composite core has a flexural modulus in a range from about 20 to about 150 GPa.

17. The cable of claim 15 , wherein the composite core has a density in a range from about 1.2 g/cc to about 1.8 g/cc.

18. The cable of claim 15 , wherein the composite core has a bending radius in a range from about 3 cm to about 40 cm.

19. The cable of claim 1 , wherein the composite core has a void fraction of about 4% or less.

20. The cable of claim 1 , wherein the composite core has:

a flexural modulus of from about 20 to about 150 GPa;

a density from about 1.3 g/cc to about 1.7 g/cc; and

a void fraction of about 3% or less.