ACCC Conductor on:
[Wikipedia]
[Google]
[Amazon]
ACCC (Aluminum Conductor Composite Core) is a registered trade mark for a type of "high-temperature low-sag" (HTLS)
It does this by replacing the steel core in ACSR cable with a 
The remaining capacity increase is provided by an increased operating temperature of continuous and emergency, compared to continuous and emergency for ACSR.
The manufacturers rate the cable for continuous operation at 180 °C surface temperature,
Operation at these temperatures implies high line losses, which may be uneconomical, but the ''ability'' to carry such current contributes to the redundancy of the electric grid (the high overload capacity can stop a potential
* The primary disadvantage is cost; ACCC costs 2.5–3 times as much as ACSR cable.
* Although ACCC has significantly less thermal sag than even other HTLS conductor designs, it has a lower axial stiffness. Therefore, it sags ''more'' than other designs under ice load, although an "ultra-low-sag" (higher modulus) version is available at a cost premium. Also, other aluminium alloys with an increased strength at the expense of electrical conductivity can be used to improve ice load sag. Ice load can also lead to the loosening of outer layer strands because of plastic deformation by the attached weight.
* Annealed aluminium is extremely soft and makes the conductor prone to surface damage.
* The conductor has a larger minimum bend radius, requiring extra care during installation.
* The conductor requires special fittings and stringing equipment that are more expensive.
overhead power line
An overhead power line is a structure used in electric power transmission and distribution to transmit electrical energy across large distances. It consists of one or more uninsulated electrical cables (commonly multiples of three for three-p ...
conductor manufactured by 34 international (and authorized) conductor manufacturers.
Invention
CTC Global (formerly Composite Technology Corporation) developed the patented technology. The ACCC conductor's composite core is manufactured according to ASTM B987 / B987M - 20 “Standard Specification for Carbon Fiber Thermoset Polymer Matrix Composite Core (CFC) for use in Overhead Electrical Conductors.” CTC Global manufactures ACCC core in the US and with partners in China and Indonesia. Finished ACCC conductor is produced by 34 conductor manufacturers worldwide under license. As of May 2021, the ACCC Conductor has been selected by over 250 utilities in 60 countries for more than 1,000 projects ranging from 11kV (AC) to 1,100kV (DC).Advantages
It is able to carry approximately twice as much current as a traditionalaluminium-conductor steel-reinforced cable
Aluminium conductor steel-reinforced cable (ACSR) is a type of high-capacity, high-strength stranded conductor typically used in overhead power lines. The outer strands are high-purity aluminium, chosen for its good conductivity, low weight, lo ...
(ACSR) cable of the same size and weight, making it popular for retrofitting an existing electric power transmission
Electric power transmission is the bulk movement of electrical energy from a generating site, such as a power plant, to an electrical substation. The interconnected lines that facilitate this movement form a ''transmission network''. This i ...
line without needing to change the existing towers and insulators.
In addition to the labor and materials savings, such an upgrade can be performed as a "maintenance and repair" operation, without the lengthy permitting process required for new construction.
It does this by replacing the steel core in ACSR cable with a carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes ...
and glass
Glass is a non-Crystallinity, crystalline, often transparency and translucency, transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most ...
fiber
Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorpora ...
strength member formed by pulltrusion. This composite strength member provides several advantages:
* It is lighter. The weight saved can be used for more aluminium conductor. ACCC cable uses trapezoid
A quadrilateral with at least one pair of parallel sides is called a trapezoid () in American and Canadian English. In British and other forms of English, it is called a trapezium ().
A trapezoid is necessarily a convex quadrilateral in Eucli ...
al strands to fit more aluminium into the same cable diameter.
* Softer, fully annealed aluminium can be used for the conductors. ACSR cable uses stronger non-annealed commercially pure aluminium which contributes to the cable's tensile strength and improves sag and pull-out under ice load, but has about 3% less electrical conductivity
Electrical resistivity (also called specific electrical resistance or volume resistivity) is a fundamental property of a material that measures how strongly it resists electric current. A low resistivity indicates a material that readily allows ...
and limits the maximum operating temperature.
* It has a much lower coefficient of thermal expansion
Thermal expansion is the tendency of matter to change its shape, area, volume, and density in response to a change in temperature, usually not including phase transitions.
Temperature is a monotonic function of the average molecular kinetic ...
(CTE) () than ACSR (). This lets the cable be operated at a significantly higher temperature without excessive sag between poles.
The first two factors result in roughly 30% greater conductivity than an equivalent ACSR conductor, allowing 14% more current to be carried at equal temperature. For example, diameter ACCC "Drake" conductor at 75 °C has an AC resistance of 106 mΩ/mile, while equivalent ACSR conductor has an AC resistance of 139 mΩ/mile, 31% higher.
The remaining capacity increase is provided by an increased operating temperature of continuous and emergency, compared to continuous and emergency for ACSR.
The manufacturers rate the cable for continuous operation at 180 °C surface temperature,
Operation at these temperatures implies high line losses, which may be uneconomical, but the ''ability'' to carry such current contributes to the redundancy of the electric grid (the high overload capacity can stop a potential cascading failure
A cascading failure is a failure in a system of interconnected parts in which the failure of one or few parts leads to the failure of other parts, growing progressively as a result of positive feedback. This can occur when a single part fails, in ...
) and thus can be valuable even when rarely used directly. Even at higher operating temperatures, the ACCC conductor's added aluminum content and lower electrical resistance offers reduced line losses compared to other conductors of the same diameter and weight.
Disadvantages
* The primary disadvantage is cost; ACCC costs 2.5–3 times as much as ACSR cable.
* Although ACCC has significantly less thermal sag than even other HTLS conductor designs, it has a lower axial stiffness. Therefore, it sags ''more'' than other designs under ice load, although an "ultra-low-sag" (higher modulus) version is available at a cost premium. Also, other aluminium alloys with an increased strength at the expense of electrical conductivity can be used to improve ice load sag. Ice load can also lead to the loosening of outer layer strands because of plastic deformation by the attached weight.
* Annealed aluminium is extremely soft and makes the conductor prone to surface damage.
* The conductor has a larger minimum bend radius, requiring extra care during installation.
* The conductor requires special fittings and stringing equipment that are more expensive.
References
{{Reflist, 30em Power cables