Multidimensional system of cascaded control of plasma form and current in tokamak with channel decoupling and H∞-controller

Consideration was given to the development and numerical modeling of the multidimensional cascaded system with H∞-controller in the external cascade for control of the plasma form and current in tokamak. For controller design, the problem of mixed sensitivity was solved by selecting the weight functions in the composite matrix of the performance criterion. The internal loop was intended for decoupling the current control channels in the magnetic coils of the tokamak poloidal fields and following the given scenario currents. Linearized models obtained from the nonlinear plasma-physical DINA code by linearizing the ITER scenario at different points were used to design the controllers. The robust stability margin was estimated in the frequency domain using singular numbers of the matrix transfer functions of the closed-loop control system. The designed cascaded system was modeled in the DINA code.