What’s commercially offered, today

Today, only ABB offers off-the-shelf equipment – its “Is-Limiter” – intended to limit fault currents, and thus their damage, before circuit breakers can act or when they are overwhelmed and fail to act. ABB describes its fault current limiter (FCL) as suitable for lines at voltages not exceeding 40.5 kV; the firm describes its mechanism thus:

The Is-limiter consists of two parallel conductors. The main conductor carries the high rated normal current (up to 5000 A). After tripping, the parallel fuse limits the short-circuit current during the first current rise (in less than 1 ms). …we use an electronically triggered charge as the switching mechanism.

(see http://www05.abb.com/global/scot/scot235.nsf/veritydisplay/8fb94bb3948fa74fc1257720003ebfb9/$file/2243%20Is-Limiter_EN.pdf).

The Is-Limiter, being a fuse, cannot restore the line to operation after the fault has ended. Instead, someone must go to the Is-Limiter and reset/replace it. Many utilities find this undesirable, especially when the limiter is to be located outside a substation.

Even when the limiter is to be placed within a substation, a fuse does not satisfy all utilities. Rather, many desire a device that will restore the network to working order seconds after the fault has ended, because many faults are transient (e.g., a momentary arc to a tree limb). The ability to limit fault currents in lines with higher voltages than 40.5 kV is also much desired; in fact, limiters that can handle 138-kV transmission lines and higher are sought.

These desires, together with the extraordinarily high cost of conventional alternatives (e.g., upgrading circuit breakers or splitting the grid into sub-grids that are electrically isolated from each other or adding air-core reactors)1, stimulate organizations around the world to develop and commercialize new kinds of fault current limiters. In the sections below, we list the organizations (including collaborations among organizations) that are currently developing FCLs for future adoption by electric utilities. Each entry includes a sentence or two about the development effort, followed by one or more URLs and/or citations by which the reader can access the organization’s most current account of its work.

What’s being developed and demonstrated now

Listed below are the world’s teams that are now working to advance Fault Current Limiters (almost all using superconductors) to the point where they will be an economic choice for electric utilities. For each team, a link is provided to what it has recently reported. Because some teams have not yet posted their most recent reports, citations to forthcoming papers may also appear.

A2A-RSE (utility)

This collaboration will test a resistive FCL on a 9.3-kV line in the greater metropolitan area of Milano, Italy.

http://cired.ir/CIRED2011/papers/CIRED2011_0339_final.pdf

L. Martini, M. Bocchi, M. Ascade, A. Valzasina, C. Ravetta, Development, testing and installation of a Superconducting Fault Current Limiter for medium voltage distribution networks, EUCAS2011

AMSC (for profit)

This firm offers a cable that it states can serve as an FCL. The voltage would be proportional to cable length (e.g., a 230-m cable is recommended for 4 kV and a 13,280-m cable for 230 kV).

http://www.AMSC.com/products/FaultBlocker/index.html?parent=2

Bruker (for profit) with Schneider Electric (for profit)

This collaboration is developing a shielded core FCL.

http://www.bruker-est.com/faultcurrent-limiters.html

Budapest University of Technology and Economics (academia)

This group has worked on shielded core FCLs in collaboration with Bruker and Areva.

http://www.supertech.vgt.bme.hu/

Chinese Academy of Sciences, CAS (R&D organization)

Recently, this group has built an all-superconducting substation that includes an FCL that the CAS had already helped build and test elsewhere on China’s grid.

http://iopscience.iop.org/1742-6596/43/1/188
http://www.asl.ee.meisei-u.ac.jp/hoshino/conference/asc06/index.html

Guomin Zhang, Shaotao Dai, Naihao Song, Zhiqin Zhu, Jingye Zhang, Wenyong Guo, Dong Zhang, Zhifeng Zhang, Liye Xiao, and Liangzhen Lin, “The Construction Progress of a High-Tc Superconducting Power Substation in China,” to appear in IEEE Trans. on Applied Superconductivity.

ECCOFLOW

Nexans leads a European consortium that includes five European utilities and many of Europe’s active HTS R&D centers. The consortium plans to test its FCL on Majorca and then in Slovakia.

http://www.eccoflow.org/
http://cired.ir/CIRED2011/papers/CIRED2011_1162_final.pdf

A. Hobl, J. Bock, J. Schramm, S. Krämer, C. Jänke, S. Elschner, M. Noe, A. Kudymov, W. Goldacker, B. Dutoit, L. Martini, M. Bocchi, P. Stoeber, P. Tixador,

Superconducting fault current limiter development based on coated conductors within the project ECCOFLOW – system aspects

, EUCAS2011

GridON with Wilson Transformer (for profit)

GridON claims to have refined the saturated core idea to the point where it can be implemented either with or without HTS components.

http://www.gridon.com/
http://www.wtc.com.au/
http://www.energytechnologies.co.uk/Home/news/11-07-11/ETI_invests_%C2%A38m_in_projects_to_enable_evolution_of_UK%E2%80%99s_electricity_distribution_networks.aspx

InnoPower (for profit)

This firm is developing a saturated core FCL for high-voltage transmission. A 220-kV demonstration is scheduled to begin soon.

http://www.innopower.com/english/product.htm?COLLCC=2858452796&

Z. L. Chen, W. Z. Gong, A. L. Ren, M. R. Zi, Z. Q. Xiong, D. J. Si, and F. Ye,

Prospective of Applications of Superconducting Fault Current Limiters in Chinese Power Grids

, EUCAS 2011

Y.Xin, W.Z.Gong, H.Hong, Y.Q.Gao, X.Y.Niu, J.Y.Zhang, J.Z.Wang, Y.W.Sun, A.L.Ren, H.Z.Wang, L.F.Zhang, Q.Li, Z.Q.Wei, L.Z.Wang, J.B.Cui, G.J.Niu, and Z.Q.Xiong,

Development of 220kV/300MVA superconductive fault current Limiter,

EUCAS 2011

KEPRI (R&D arm of KEPCO, a utility) and LS (for profit)

This collaboration has developed a fast resistive FCL that is now being tested in KEPCO’s Icheon substation.

http://www.KEPRI.re.kr/

(English>R&D Support>R&D Activity>Transmission&Distribution Laboratory> Applied Superconductivity and Underground Transmission Lab)

http://cired.ir/CIRED2011/papers/CIRED2011_0801_final.pdf

Hye-Rim Kim, Seong Eun Yang, Seung-Duck Yu, Heesun. Kim, Woo-Seok Kim, Choong-Yeol Park, Seong-Woo Yim, Kwon-Bae Park, Jungwook Sim, Young-Geun Kim, and Ok-Bae Hyun,

Fabrication of an SFCL for demonstration in a real grid,

EUCAS 2011

Krzhizhanovsky Power Engineering Institute (ENIN) and Lebedev Physical Institute (R&D organizations)

At the bench-scale, the partners are exploring the use of YBCO coated conductor as a nonlinear resistor connected across the transformer secondary terminals in order to make an FCL.

http://ewh.ieee.org/tc/csc/europe/newsforum/pdf/2010-ASC/ST250.pdf

Kurchatov Institute (R&D organization) and Russian Superconductor Corp. (for profit)

This collaboration designed and tested a low-power, resistive FCL. Little has appeared in the public domain.

http://www.cca2010.org/PDF/overview.pdf

Kyushu Electric (utility)

This utility and its partners (Kyusho Univ, ISTEC, Fujikura and Showa) are developing a REBaCuO transformer that also limits fault currents. A recent test confirmed the design’s FCL capacity.

http://www.istec.or.jp/web21/pdf/11_Winter/E3.pdf

Lenin Energy Institute, VEI (R&D organization)

VEI is investigating a resistive FCL with a fast-acting vacuum interrupter switch.

http://ewh.ieee.org/tc/csc/europe/newsforum/Contents11.html

Nagoya University (academic) and CRIEPI (R&D arm of utility industry)

This collaboration is now developing a 2-MVA, 22-kV/6.6-kV transformer incorporating REBaCuO coils. Both numerical simulation and laboratory tests have shown that this device can limit fault currents.

https://ewh.ieee.org/tc/csc/europe/.../abstract-ASC2010-ST220.html

Nexans (for profit)

This firm has recently demonstrated its resistive FCLs (incorporating Bi-2212) in the grid in both Germany and the UK. More demonstrations are scheduled.

http://www.nexans.de/eservice/navigation/NavigationPublication.nx?publicationId=-24471&navigationId=251736
http://www.nexans.de/eservice/navigation/NavigationPublication.nx?publicationId=-30414&navigationId=148777
http://cired.ir/CIRED2011/papers/CIRED2011_0352_final.pdf

Rolls-Royce and HyperTech (for profit)

This collaboration is developing a resistive FCL that incorporates MgB2 wire because it is much, much less expensive than today’s REBaCuO tape.

http://www.hypertechresearch.com/page5.html
http://www.cired.be/CIRED09/round_tables/RT1b/Dr%20P%20D%20Hopewell%20RT1b.pdf
http://www.energytechnologies.co.uk/Home/news/11-07-11/ETI_invests_%C2%A38m_in_projects_to_enable_evolution_of_UK%E2%80%99s_electricity_distribution_networks.aspx

M. Majoros, M. D. Sumption, M. A. Susner, C. Myers, E. W. Collings, M. Tomsic, M. Rindfleisch, J. Phillips, D. Lyons and J. Yue,

Current limiting properties of a superconducting coil wound noninductively using a wind-and-react MgB2 cable – experiments and FEM modeling.

EUCAS2011

Shanghai Jiaotang University (academic) and Gan-Shan Shanghai (for profit)

With funding from Gan-Shan Shanghai, members of the Power Engineering Dept. are working with members of the Physics Dept. to build a 10-kV, resistive FCL that incorporates REBaCuO tape.

http://english.seiee.sjtu.edu.cn/Research.aspx
http://en.cnki.com.cn/Article_en/CJFDTOTAL-JSDQ201005006.htm
http://en.cnki.com.cn/Article_en/CJFDTOTAL-DLZD200804005.htm
http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5668899

Siemens-Nexans-AMSC (for profit)

This group’s effort recently culminated in a successful test at Power Tech of a 138-kV, single-phase resistive FCL.

IEEE Transactions onApplied Superconductivity

, 19(3):1950-1955 (June 2009) [ISSN: 1051-8223; Digital Object Identifier: 10.1109/TASC.2009.2017902; Date of Current Version: July 17, 2009] Hans-Peter Kraemer, Wolfgang Schmidt, Hong Cai, Bruce Gamble, David Madura, Tim MacDonald, Joe McNamara, Walther Romanosky, Greg Snitchler, Nicolas Lallouet, Frank Schmidt, Syed Ahmed,

Superconducting Fault Current Limiter for Transmission Voltage,

EUCAS2011

SuperPower, Inc., and Waukesha Electric (for profit)

The partners are working to build a power transformer that will also limit fault currents.

http://www.waukeshaelectric.com/transformers/tech_leadership.html
http://www.superpower-inc.com/content/hts-transformer-and-sfcl-transformer
http://www.superpower-inc.com/content/fault-current-limiters

Zenergy (for profit)

This firm continues to refine its designs for a saturated core FCL. Currently, it is shipping medium-voltage FCLs to the UK. Next year, it plans to demonstrate a 138-kV system on the grid in the United States. http://www.zenergypower.com/index.php/en/products/fault-current-limiter

http://cired.ir/CIRED2011/papers/CIRED2011_0680_final.pdf

The following organizations’ efforts also merit attention:

Applied Superconductor Ltd

This firm supplies others’ FCLs to utilities. Its expertise is in eliciting the differing needs within a utility and putting together equipment to meet those needs. By doing so, it has made England a center for in-grid FCL demonstrations.

http://www.appliedsuperconductor.com/
http://cired.ir/CIRED2011/papers/CIRED2011_0456_final.pdf

Energy Technologies Institute

This firm is owned by both the UK government and privately held firms. Its goal is to develop and commercialize technology that will enable the UK to rely more on renewables. To that end, the firm is financing two FCL demonstrations in the English grid.

http://www.energytechnologies.co.uk/Home/news/11-07-11/ETI_invests_%C2%A38m_in_projects_to_enable_evolution_of_UK%E2%80%99s_electricity_distribution_networks.aspx

Developers Of Fault Current Limiters That Do Not Incorporate Superconductors

GridON with Wilson Transformer (for profit)

The collaborators state they have refined the saturated core idea to the point where it can be implemented either with or without HTS components. With support from ETI, the collaborators have announced a UK demonstration of the design without HTS.

http://www.gridon.com/
http://www.wtc.com.au/
http://www.energytechnologies.co.uk/Home/news/11-07-11/ETI_invests_%C2%A38m_in_projects_to_enable_evolution_of_UK%E2%80%99s_electricity_distribution_networks.aspx

Innovative Technomics (for profit)

This firm makes equipment, embodying conventional materials, to protect motors. The firm recently announced plans for a dedicated FCL.

http://www.innovativetechusa.com/DFCL.html
http://perso.numericable.fr/~jlmichel/e_DFCL.htm
http://www.ieee-pes.org/images/pdf/isgt2010/january_21_2010/6-power-energy/10SG0125-Innovative-DFCL-Prafulla-Deo-Final.pdf

Silicon Power (for profit)

This firm is working closely with EPRI to build 15-kV and 69-kV (modular) FCLs that incorporate power electronics.

http://www.siliconpower.com/Systems.asp

Zenergy (for profit)

This firm recently announced its intent to build upon its experience, gained from developing superconducting FCL, to use only conventional materials within an FCL that could operate on 4kV – 15kV lines.

http://www.zenergypower.com/images/press_releases/2011/2011-10-18-fcl-testing-update.pdf

Professional Groups Working to Draft Standards

The committees listed below are drafting FCL standards and developing a common FCL vocabulary.

CIGRE WG D1.38 Emerging Test Techniques Common to High Temperature Superconducting (HTS) Power Systems

Convenor: Mathias Noe (KIT) E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

CIGRE WGA3.23 Application and Feasibility of Fault Current Limiters in Power Systems

Convenor: Heino Schmitt (Siemens) E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

IEEE WG C37.302 Fault Current Limiter Testing

Convenor: Mischa Steurer (CAPS) E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Secretary: Frank C. Lambert (NEETRAC) E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it