Active control of current distribution and stability of superconducting magnet by subdividing the conductor

Non-uniform current distribution in super-conducting magnet conductor causes serious deterioration of stability and increase in pulse field loss especially in large-scale conductors. To clear those problems we proposed the parallel sub-conductor system in which the main conductor was subdivided into sub-conductors arranged in parallel. Each of the sub-conductors is electrically insulated from the others and connected to an individual power supply. With this arrangement the current of each sub-conductor can be controlled separately and the current distribution in the sub-conductors can be actively controlled. We performed an experiment using a magnet wound of four-parallel sub-wires and demonstrated that the current distribution was quickly controlled and the magnet was actively stabilized by transferring the current from quenching sub-wire to the other sub-wires.