Feedback Control of No-Insulation High Temp. Superconductor Magnet

An active feedback control system to operate a no-insulation (NI) high temperature superconductor (HTS) magnet. The NI HTS winding technique is effective in building an extremely compact, stable, and mechanically robust HTS magnet. However, the presence of the "partially shorted radial" current path, in addition to the designed spiral path, produced by the turn-to-turn contacts causes a substantial charging delay, and the charging delay produces a non-linear "magnet constant." An active control of the field by active control of the power supply current provides operational solutions for these challenges and is critical for application of the NI HTS technique to actual high field user magnets.