Aluminum power cables for wind turbines took a giant leap forward with the introduction of Helukabel’s Heluwind WK Powerline ALU. This power cable is made of finely-stranded aluminum and is highly flexible, providing the performance capabilities of a standard copper cable, but at a fraction of the cost.
“Because the Powerline ALU is made of aluminum its weight is reduced by nearly 50%, it is quicker and easier to install, as well as being less expensive than comparable copper power cables,” says Uwe Schenk, Global Segment Manager – Wind at Helukabel. “Given the uncertainty of the PTCs and the need for reducing turbine costs (manufacturing, installation and maintenance), the Powerline ALU is our attempt to further development of the industry in the U.S. and Canada by making wind turbines more affordable.”
Conventional aluminum power cables are stiff and unable to bend, which prevents the installation of a single cable length. Wind turbine installers are forced to interrupt the cable by splicing it up to 80 times in four tower sections to connect the stiff aluminum cable across the length of the down tower. Once the base is reached, an additional interruption in the cable is needed to make the flex connection to the inverter. This installation process takes two to three days.
The installation advantage of the flexible the aluminum cable is that one length can run from behind the drip loop in the down tower area directly to the inverter in the tower base. It requires only one splice, between the copper loop cable and the power line, and a crimp cable lug to connect the power line to the inverter. This enhanced installation procedure takes only four to six hours.
Additionally, reducing the splice count to one improves the safety and protection of the turbine’s power cable because most technical failures are caused by bad splices.
Constructing the cable with a finely-stranded aluminum core and wrapping it with specially-formulated, heat-resistant insulation, and outer jacket, make it highly flexible and extremely durable with resistance to UV-light, oil and fire. Additional characteristics include:
- Broad operating temperature range: –20°C (flexing) and -40°C (fixed) to +105°C for both.
- Tight bending radius: 10x cable diameter for flexing, 4x cable diameter for fixed applications
- Recyclable (ROHS)
- Halogen-free (LSZH)
The cable comes in two standard types, 0.6/1 kV and 1.8/3 kV, and can be ordered in bulk or pre-assembled (includes tube connector and crimped cable lug). Both types are available in a more durable version which feature an abrasion-resistant and cut-resistant outer jacket.