Validation of plasma shape reconstruction by the method of Cauchy-condition surface in KSTAR

Miyata, Yoshiaki; Hahn, S.-H.*; Suzuki, Takahiro; Ide, Shunsuke

The accurate plasma shape reconstruction is essential for plasma equilibrium control and analysis. Various methods to reconstruct a plasma shape have been developed for constructions of tokamak devices. A plasma shape has been reconstructed by the method of Cauchy condition surface (CCS) from the magnetic measurements in JT-60U. The CCS calculation can reconstruct the outermost magnetic surface, and calculate the quantities related to plasma shape such as the Shafranov lambda, the safety factor, and so on. It was found that the plasma shape reconstructed by CCS calculation agreed well with the measurements in KSTAR. CCS is robust at Ip ramp up/down even with small Ip. In this presentation, the result of first application of CCS to the KSTAR plasma is discussed.