Stability and quench test results of the kA class conductor for a /spl mu/SMES coil

We are developing the small-sized superconducting magnetic energy storage (/spl mu/SMES) coil with the storage capability of 3 megajoules, which provides electric power with high quality to sensitive electric loads. As the initial step in fabrication of the /spl mu/SMES coil, a kA class conductor with a high copper to superconductor ratio was selected as a candidate conductor. The conductor was tested in two points of view, which are important in development of the stable /spl mu/SMES coil. First, the stabilities of the conductor against localized disturbances such as wire motions were measured by using a wire heater. Second, the quench current characteristics for different charge rates were also tested. The stability data showed that the short heat pulses made the conductor more unstable. The conductor had relatively high recovery currents ranging between 40% and 50% of its critical currents, compared with the conductors with a low copper ratio. The quench tests indicated that the quench currents of the conductor were independent of current ramp rates up to 3000 A/s and nearly equal to its critical current data.