Superconducting magnetic energy storage and superconducting self-supplied electromagnetic launcher

Abstract

Abstract. Superconductors can be used to build energy storage systems called Superconducting Magnetic Energy Storage (SMES), which are promising as inductive pulse power source and suitable for powering electromagnetic launchers. The second generation of high critical temperature superconductors is called coated conductors or REBCO (Rare Earth Barium Copper Oxide) tapes. Their current carrying capability in high magnetic field and their thermal stability are expanding the SMES application field. The BOSSE (Bobine Supraconductrice pour le Stockage d'Energie) project aims to develop and to master the use of these superconducting tapes through two prototypes. The first one is a SMES with high energy density. Thanks to the performances of REBCO tapes, the volume energy and specific energy of existing SMES systems can be surpassed. A study has been undertaken to make the best use of the REBCO tapes and to determine the most adapted topology in order to reach our objective, which is to beat the world record of mass energy density for a superconducting coil. This objective is conflicting with the classical strategies of superconducting coil protection. A different protection approach is proposed. The second prototype of the BOSSE project is a small-scale demonstrator of a Superconducting Self-Supplied Electromagnetic Launcher (S3EL), in which a SMES is integrated around the launcher which benefits from the generated magnetic field to increase the thrust applied to the projectile. The S3EL principle and its design are presented. Motivation SMES principle [1]Superconductors have the property to lose their electrical resistivity when they are cooled under a critical temperature T C . Even if energy dissipation occurs in a superconductor submitted to variable electrical current or magnetic induction (B), there is no energy dissipation in a steady state. If a superconducting winding is supplied, then short-circuited current is not dissipated by Joule effect and magnetic energy is conserved almost indefinitely. This is the principle of inductive storage with superconductors, generally called SMES (Superconducting Magnetic Energy Storage).The stored energy E mag can be expressed as a function of inductance L and current I or as the integral over space of the product of magnetic field H by induction B, following (1):Once the SMES has been charged and short-circuited, the energy is available and can be used by opening the short circuit and connecting the SMES to a load. It can be connected to the load either directly as in the case of direct supply of an electromagnetic launcher, or through a voltage adaptation system if the discharge has to be controlled. SMES have low energy density compared to batteries, but high power densities. Furthermore, they can have high cycling yield (97%), with the cycling yield being defined as the recovered energy divided by the energy provided to the SMES, including the energy spent to cool the system, after one cycle. They are direct electricity storage devices such as capacitors. Nevertheless, ...

Essential Material Knowledge and Recent Model Developments for REBCO-Coated Conductors in Electric Power Systems

“…As a matter of fact, some large-scale applications have already demonstrated the reliability of using kilometers of tapes relying on metal-to-metal electrical connection or splices [ 77 ]. However, the main issue is the variability of the critical current along the length of the conductor (inhomogeneity) and its anisotropy concerning the direction of the magnetic field [ 78 , 79 ]. The manufacturers provide some statistics on the critical current along the tape length, which has not been exploited yet.…”

Generation of 25 T with an all-superconducting magnet system: field profile and field quality measurements of a layer-wound 4 T REBCO insert coil for a 21 T LTS magnet

“…Due to higher minimum quench energies [16,17] and significantly lower normal zone propagation velocities [18,19], HTS coils are challenging to operate safely. In contrast to LTS magnets, a localized normal conducting region can develop into a hotspot leading to the thermal degradation or the destruction of the conductor.…”

Influence of “Productive” Impurities (Cd, Na, O) on the Properties of the Cu2ZnSnS4 Absorber of Model Solar Cells

“…Note that various options have already been proposed and successfully developed for energy converters, such as solar batteries [1]- [3], wind generators [4], [5], geothermal converters [6], as well as for different energy storage devices, such as a superconducting inductive storage [7]. To improve the performance of these systems, new properties of solar radiation absorbers [8]- [10], quasi-two-dimensional materials [11]- [13], superconductors [14]- [16] and others are being searched.…”