Observation of poloidal current flowed to the vessel after failure of vertical position feedback control in EAST Tokamak

Plasmas with vertically elongated cross-sections tend to be unstableto an axis-symmetric instability. This paper studies themagnetohydrodynamic equilibria in elongated plasmas after failure ofvertical feedback control by using magnetic data for EAST device.Vertical forces on the vessel due to the induced polodial andtoroidal currents are evaluated. The maximum force of the Fz_pol in vertical displacement events for EAST designed parametersis given.