MgB2 wires have been provided by several manufacturers, showing enough critical current (Ic) for practical applications in relatively low-field. Because the MgB2 has critical temperature above boiling temperature of hydrogen, dc power distribution system with low carbon emission using MgB2 superconducting magnetic energy storage (SMES), named advanced superconducting power conditioning system has been proposed. For the system, the MgB2 coil production technology obtaining 30 kJ stored energy the investigation about the SMES coil consists of 600 A, 1.7-T Rutherford-type conductors made of commercially-available MgB2 wires. Due to strain sensitivity before/after heat treatment for MgB2 production, the proper designs of the large-scale twisted conductors both in wind and react, react and wind methods are needed, choosing optimized twist pitches and cable compaction factors. To demonstrate the SMES coil performance, we have been carried out the test campaign of conductors and small prototype coils in various temperature and background field conditions. These results are used for a computer simulation for estimating full size double pancake coil performance of the system, based on the non-steady state heat conduction analysis. The calculated result seems to be a good tool for predicting coil performance for the large capacity energy storage operation.
- Large-scale conductor
- MgB strand
- rutherford cable
- superconducting magnetic energy storage (SMES)