Energy kites are increasingly being looked at as an alternative to wind turbine power generation technology. By replacing the massive steel towers of conventional wind turbines with lightweight hardware and smart software, energy kite developers hope to unlock access to wind resources too expensive or impractical to access with traditional wind technologies.
Since 1952, United Equipment Accessories (UEA) has provided solutions for many complex applications that require rotational electrical transfer using slip rings. UEA is a leading global supplier of pitch control slip rings in traditional wind turbine applications, with its slip rings installed in more than 35,000 wind turbines installed globally. Using our traditional wind technology background, our engineering team has applied its decades of slip ring design knowledge to design a slip ring for such unique kite energy applications.
The wind energy kite technology typically consists of a kite tethered to a ground station. The ground station has a ground side gimbal to handle the de-twist of the tether associated with the continuous circular or oval flight paths of the kite. The ground station can have up to two slip rings, one slip ring behind the drum used to reel in the tether, and one slip ring behind the de-twist required during the continuous circular or oval flight paths. The graphic below shows the kite design with two types of slip rings needed for the application.
Because of the limited space in the ground station gimbal barrel, the challenge was to develop a high voltage slip ring capable of handling two electrical phases rated for approximately 200 Amps continuous currents @ 7500 VDC with hi-pot resistance between the phases of up to 16,500 VDC. To fulfill these electrical requirements within the ground station's very tight form factor (< 170 mm inner diameter, < 380 mm length, and a 19 mm through-bore) presents a unique challenge for such a kite slip ring application. Risk priority evaluations rank slip rings as a highly critical component, and identifying slip ring capable of at least 50 million revolutions are a vital risk mitigation strategy for kite developers.
UEA's core value of creative problem solving is on clear display by developing such a unique solution for energy kites. We are consistently adding to our vast knowledge base to be even better prepared to assist customers with similar challenges! Contact us for your custom rotary solution!