The Design to Downsize a Conduction-Cooled LTS Pulse Coil for UPS-SMES as Protection From Momentary Voltage Drops

• Published in: IEEE Transactions on Applied Superconductivity Vol. 17; no. 2; pp. 1963 - 1966
• Main Authors: Kawagoe, A., Tsukuda, S., Sumiyoshi, F., Mito, T., Chikaraishi, H., Hemmi, T., Baba, T., Yokota, M., Morita, Y., Ogawa, H., Abe, R., Nakamura, A., Okumura, K., Kuge, A., Iwakuma, M.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2007; Institute of Electrical and Electronics Engineers (IEEE); Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Aluminum base alloys; Applied sciences; Coiling; Coils; Coils (windings); Conduction cooling; Conductors; Direct energy conversion and energy accumulation; Disturbances. Regulation. Protection; Electric potential; Electrical engineering. Electrical power engineering; Electrical power engineering; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Energy accumulation; Exact sciences and technology; Finite element methods; LTS; Niobium compounds; Power electronics, power supplies; Power networks and lines; Protection; pulse coil; SMES; Spacers; Stability; Stability analysis; Thermal analysis; Thermal conductivity; Thermal stability; Titanium compounds; Voltage; Voltage drop; Thermal stress; Stability margin; Thermal management (packaging); Electric stress; Voltage fall; Temperature effect; Power system stability; Conduction cooling; Power supply; LTS; Stability criterion; Voltage stability; Power system load; Fibre reinforced plastics; Superconducting magnet energy storage; Machine windings; Negative bias temperature instability; Cooling; pulse coil; Power electronics; Two dimensional model; SMES; Overload; Uninterruptible power supply; Spacer; Cooling system; Maximum temperature; Thermal analysis; Miniaturization; Reliability; AC losses; Energy storage
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2007.898394

The stability margin of a conduction-cooled LTS pulse coil with stored energy of 1 MJ, which is used for UPS-SMES as protection from momentary voltage drops, is estimated from thermal analyses using the two-dimensional finite elementary method. How much the 1 MJ coil is able to be downsized is discussed. The winding conductor of this coil is a NbTi/Cu Rutherford cable, which is extruded with aluminum. Dyneema FRP and Litz wires are used as the spacers of this coil. In the design of this 1 MJ coil, the effects of spacers were neglected. In order to estimate the stability margin, thermal analyses was carried out by taking into account the thermal effects of spacers, for the coil during overload operation. And it was checked whether the maximum temperature The results showed that the 1 MJ coil has a large stability margin of 8 times the rated ac loss. In addition, new coils with a stability margin of about two times were designed. Possibilities for reducing the size and the cost of a 1 MJ LTS pulse coil are also shown.