Recent experimental results of reversed field pinch (RFP) and ultra-low safety factor q (ULQ) configurations have been achieved with preionization, air core transformer power crowbar, vacuum chamber discharge cleaning, carbonization and titanium gettering. The plasma properties were improved. A plasma current flat-top appeared, and the plasma current value was increased. The impurities were controlled effectively, and the plasma temperature was increased by carefully controlling the wall conditions. A stable confinement RFP configuration was obtained. Stable and relaxation ULQ discharges have been aachieved in different q value operations. An increase in the toroidal flux was generated by a dynamo effect, with the plasma current rising for ULQ discharges.
展开▼
