Featured Research

from universities, journals, and other organizations

Superconducting current limiter guarantees electricity supply of the Boxberg power plant

Date:
January 13, 2012
Source:
Helmholtz Association of German Research Centres
Summary:
For the first time, a superconducting current limiter based on YBCO strip conductors has now been installed at a power plant. At the Boxberg power plant of Vattenfall, the current limiter protects the grid for own consumption that is designed for 12,000 volts and 800 amperes against damage due to short circuits and voltage peaks.

Superconducting coils are cooled with liquid nitrogen and have zero resistance to current flow.
Credit: Martin Lober, KIT

For the first time, a superconducting current limiter based on YBCO strip conductors has now been installed at a power plant. At the Boxberg power plant of Vattenfall, the current limiter protects the grid for own consumption that is designed for 12 000 volts and 800 amperes against damage due to short circuits and voltage peaks. The new technology co-developed by Karlsruhe Institute of Technology and made by Nexans SuperConductors enhances the intrinsic safety of the grid and may help reduce the investment costs of plants.

"For a long time, high-temperature superconductors were considered to be difficult to handle, too brittle, and too expensive for general industrial applications," explains project manager Wilfried Goldacker from Karlsruhe Institute of Technology. "The second generation of high-temperature superconductor wires based on YBCO ceramics is much more robust. Properties have been improved." Superconducting current limiters work reversibly. In case of current peaks after short circuits in the grid, no components are destroyed. The limiter automatically returns to the normal state of operation after a few seconds only. Consequently, the power failure is much shorter than in case of conventional current limiters, such as household fuses, whose components are destroyed and have to be replaced with a high time and cost expenditure.

"Superconducting current limiters have a number of advantages for the stability of medium- and high-voltage grids," explains Mathias Noe, Head of the Institute of Technical Physics of Karlsruhe Institute of Technology. Reliable, compact current limiters enhance the operation stability of power grids and allow for a simplification of the grid structure. As they are protected against current peaks, decentralized energy generators, such as wind and solar systems, can be integrated much better in grids. Expensive components in the existing grid are protected efficiently, components in future grids can be designed for smaller peak currents, and transformers will no longer be necessary. Investment costs of power plants and grids will be reduced. Moreover, superconducting current limiters on the basis of YBCO can also be applied in high-voltage grids of more than 100 kilovolts for better protection against power failures in the future.

YBCO stands for the constituents of the superconductor: Yttrium, barium, copper, and oxygen. An YBCO crystal layer of about 1 micrometer in thickness is grown directly on a stainless steel strip of a few millimeters in width that gives the ceramics the necessary stability. Below a temperature of 90 Kelvin or minus 183 Celsius, the material becomes superconductive. However, superconductivity collapses abruptly when the current in the conductor exceeds the design limits. This effect is used by the current limiter. In case of current peaks in the grid, the superconductor loses its conductivity within fractions of a second and the current will flow through the stainless steel strip only, which has a much higher resistance and, thus, limits the current. The heat arising is removed by the cooling system of the superconductor. A few seconds after the short circuit, it is returned to normal operation in the superconducting state. YBCO superconducting layers on stainless steel strips are more stable and operation-friendly than first-generation superconductors based on BSCCO ceramics. Moreover, their production does not require any noble metals, such as silver, and will presumably be cheaper.

The superconducting current limiter was developed in the past two years under the ENSYSTROB project. The project partners are Karlsruhe Institute of Technology, Nexans SuperConductors, TU Dortmund, and BTU Cottbus. The field test will be carried out at the user, the Vattenfall utility company. The project was funded with about EUR 1.3 million by the Federal Ministry of Economics. The results of the project are of high relevance, as the functionality of current limitation may be integrated in superconducting transformers and energy cables in the future.


Story Source:

The above story is based on materials provided by Helmholtz Association of German Research Centres. Note: Materials may be edited for content and length.


Cite This Page:

Helmholtz Association of German Research Centres. "Superconducting current limiter guarantees electricity supply of the Boxberg power plant." ScienceDaily. ScienceDaily, 13 January 2012. <www.sciencedaily.com/releases/2012/01/120113102048.htm>.
Helmholtz Association of German Research Centres. (2012, January 13). Superconducting current limiter guarantees electricity supply of the Boxberg power plant. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2012/01/120113102048.htm
Helmholtz Association of German Research Centres. "Superconducting current limiter guarantees electricity supply of the Boxberg power plant." ScienceDaily. www.sciencedaily.com/releases/2012/01/120113102048.htm (accessed July 30, 2014).

Share This




More Matter & Energy News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Climate Change Could Cost Billions, According To White House

Climate Change Could Cost Billions, According To White House

Newsy (July 29, 2014) A report from the White House warns not curbing greenhouse gas emissions could cost the U.S. billions. Video provided by Newsy
Powered by NewsLook.com
Stranded Whale Watching Boat Returns to Boston

Stranded Whale Watching Boat Returns to Boston

Reuters - US Online Video (July 29, 2014) Passengers stuck overnight on a whale watching boat return safely to Boston. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Baluchistan Mining Eyes an Uncertain Future

Baluchistan Mining Eyes an Uncertain Future

AFP (July 29, 2014) Coal mining is one of the major industries in Baluchistan but a lack of infrastructure and frequent accidents mean that the area has yet to hit its potential. Duration: 01:58 Video provided by AFP
Powered by NewsLook.com
Easier Nuclear Construction Promises Fall Short

Easier Nuclear Construction Promises Fall Short

AP (July 29, 2014) The U.S. nuclear industry started building its first new plants using prefabricated Lego-like blocks meant to save time and prevent the cost overruns that crippled the sector decades ago. So far, it's not working. (July 29) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins