The pedestal structure of the high-confinement mode (H-mode) operation strongly impacts global confinement and fusion performance in tokamak devices. Studies of the pedestal structure also play an important role in better understanding the characterization of H-mode plasma discharges with type-I edge localized modes on the Experimental Advanced Superconducting Tokamak (EAST). The EPED model has been widely validated to predict the pedestal structure of several tokamak devices. The mean pedestal width Δ ψ correlates with the square root of the poloidal pedestal beta β p , p e d 1 / 2 and is in good agreement with Δ ψ = 0.12 β p , p e d 1 / 2 from experimental observations. It is also found that the scaling coefficients of Δ ψ and β p , p e d 1 / 2 may have no dependence on the heating schemes. The comparison of predictions with measurements indicates that the REPED model could be used to predict the pedestal height for a range of experimental pedestal pressures (

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Helium (He) plasmas will be used to test the operationally relevant systems and plasma diagnostics during the ITER non-nuclear phase. Analyses of pedestal width and height in recent DIII-D H-mode experiments in He plasmas find good agreement with between the pedestal width Δ ψ and the square root of the poloidal pedestal beta from experimental observations. The EPED/REPED pedestal model is found to be applicable to predict the pedestal structure of the He plasma from comparison of predictions with experiments. Furthermore, it indicates that the pedestal height of He and deuterium (D) plasmas are similar from the REPED predictions with the same global parameters, and the pedestal width of He is approximately 6% larger than that of D.