EFIT Equilibrium Fitting code#
EFIT (Equilibrium Fitting) is a computer code developed to translate measurements from plasma diagnostics into useful information like plasma geometry, stored energy, and current profiles. The measuremnts are obtained from diagnostics such as external magnetic probes, external poloidal flux loops, and the Motional Stark Effect (MSE), which measures the direction of the magnetic field lines inside the plasma. The Grad-Shafranov equilibrium equation, which describes the force balance in a plasma, is solved using the available measurements as constraints on the toroidal current density. Since the current also depends on the solution of the equation, the poloidal flux function, this is a nonlinear optimization problem. The equilibrium constraint allows the two-dimensional current density to be represented by two one-dimensional stream functions (functions only of flux), which significantly reduces the complexity of the problem.
The version of the code described here is machine independent, portable, and has better performance than the original GA version. It is also being designed with the goal of connecting to other components of the EFIT-AI project.
EFIT-AI documentation#
EFIT is part of the larger EFIT-AI project.
Documentation on other project can be found at:
User documentation#
Developer documentation#
EFIT-AI documentation#
EFIT is part of the EFIT-AI project.
Related documentation from this project:
Search#
Bibliography#
- LJS+85
L L Lao, H St John, R D Stambaugh, A G Kellman, and W Pfeiffer. Reconstruction of current profile parameters and plasma shapes in tokamaks. Nuclear Fusion, 25(11):1611, 1985.
- LKA+22
L L Lao, S Kruger, C Akcay, P Balaprakash, T A Bechtel, E Howell, J Koo, J Leddy, M Leinhauser, Y Q Liu, S Madireddy, J McClenaghan, D Orozco, A Pankin, D Schissel, S Smith, X Sun, and S Williams. Application of machine learning and artificial intelligence to extend EFIT equilibrium reconstruction. Plasma Physics and Controlled Fusion, 64(7):074001, jun 2022. URL: https://doi.org/10.1088/1361-6587/ac6fff, doi:10.1088/1361-6587/ac6fff.
- LJP+05
LL Lao, HE St John, Q Peng, JR Ferron, EJ Strait, TS Taylor, WH Meyer, C Zhang, and KI You. Mhd equilibrium reconstruction in the diii-d tokamak. Fusion science and technology, 48(2):968–977, 2005.