Study of the poloidal beta and internal inductance by solving the simplest Grad–Shafranov equation for a tokamak with a circular cross section

In this work, we present the poloidal beta $\beta_p$ and internal inductance $l_i$ by solving the simplest Grad–Shafranov equation (GSE), using the Solov'ev assumption for an HT-7 tokamak with a circular cross section. The poloidal beta and internal inductance are measured by using diamagnetic and compensation loops, combined with poloidal magnetic probe array signals. In this paper, theoretical and experimental results of determining $\beta_p$ and $l_i$ are presented. The calculated poloidal beta and internal inductance are demonstrated to depend on the kind of the discharge or plasma current.