Trends in cables

摘要

Cables span the wind industry from work in the nacelle, throughout the wind farm and substations, and then across the country in several grids, and all at various voltages. The power cable in a nacelle may have the toughest job on a wind farm. In a nacelle, the cable from a generator may have to tolerate millions of twists, dripping oil, and cold winter temperatures. An improving tolerance to each of these conditions describes cable trends. Wind turbines transmit power from their generators to ground-based equipment through large cables capable of handling many Amps. But there are no slip rings to get this power out of a turning nacelle. To accommodate the necessity of yaw, the cable is run up the side of a tower, over a 180° strain relief, into about 3-m long loop and then into the nacelle. This "slack" accommodates nacelle motion. But as you can imagine, in cold weather, cables stiffen, so the stranded copper conductors and insulation should be of a composition that stays flexible. "Tests conducted in Europe involve 5 million twists at about five rpm," says Lapp USA Senior Product Manager Rick Orsini.