This paper proposes a system-level approach suitable to analyze the performance of a dynamic Wireless Power Transfer System (WPTS) for electric vehicles, accounting for the uncertainty in the vehicle trajectory. The key-point of the approach is the use of an analytical behavioral model that relates mutual inductance between the coil pair to their relative positions along the actual vehicle trajectory. The behavioral model is derived from a limited training data set of simulations, by using a multi-objective genetic programming algorithm, and is validated against experimental data, taken from a real dynamic WPTS. This approach avoids the massive use of computationally expensive 3D finite element simulations, that would be required if this analysis were performed by means of look-up tables. This analytical model is here embedded into a system-level circuital model of the entire WPTS, thus allowing a fast and accurate analysis of the sensitivity of the performance as the actual vehicle trajectory deviates from the nominal one. The system-level analysis is eventually performed to assess the sensitivity of the power and efficiency of the WPTS to the vehicle misalignment from the nominal trajectory during the dynamic charging process.
The self-consistent electromagnetic integration of tokamak plasma magnetohydrodynamic (MHD) models with external conductors is considered in this manuscript. We integrate the extended MHD code JOREK and the eddy current code CARIDDI, via a scheme based on the virtual casing principle enabling two-way coupled fully implicit simulations. The robustness of this new integrated tool is validated against JOREK-STARWALL and CarMa0NL simulations for vertical displacement events in a simplified ASDEX Upgrade-like geometry and for n = 1 tearing modes in a circular high-aspect-ratio tokamak. The impact of 3D wall structures on the plasma evolution is highlighted introducing ports at different locations of a simplified axisymmetric wall and characterizing its effect on the plasma evolution. In addition to realistically capturing the 3D interactions between plasma and wall structures, the coupled codes will allow in the future 1:1 comparisons to experiments using virtual magnetic diagnostics that capture screening effects accurately.
The possibility of generation of the rotating sideways force on the wall by the kink modes is analytically investigated. The approach is basically the same as that developed earlier in (Mironov and Pustovitov 2017 Phys. Plasmas24 092508) for the locked modes, but now their rotation is allowed. Its main elements are ∂b/∂t ≠ 0 (described by the growth rate γ and angular rotation frequency ω of the magnetic perturbation b), resistive dissipation in the wall, and the requirement of zero sideways force on the plasma. These make the approach greatly different from those resulting in the so-called Noll’s formula. The result is also different; it predicts a force an order of magnitude smaller. Nevertheless, such a force can be dangerous at the resonance frequency of the vacuum vessel. The derived relations show that the rotating force must be maximal at ωτw = O(1), where τw is the resistive wall time. For the faster modes it decreases roughly as ∼1/ω.
COMPASS addressed several physical processes that may explain the behaviour of important phenomena. This paper presents results related to the main fields of COMPASS research obtained in the recent two years, including studies of turbulence, L–H transition, plasma material interaction, runaway electron, and disruption physics: Tomographic reconstruction of the edge/SOL turbulence observed by a fast visible camera allowed to visualize turbulent structures without perturbing the plasma. Dependence of the power threshold on the X-point height was studied and related role of radial electric field in the edge/SOL plasma was identified. The effect of high-field-side error fields on the L–H transition was investigated in order to assess the influence of the central solenoid misalignment and the possibility to compensate these error fields by low-field-side coils. Results of fast measurements of electron temperature during ELMs show the ELM peak values at the divertor are around 80% of the initial temperature at the pedestal. Liquid metals were used for the first time as plasma facing material in ELMy H-mode in the tokamak divertor. Good power handling capability was observed for heat fluxes up to 12 MW m−2 and no direct droplet ejection was observed. Partial detachment regime was achieved by impurity seeding in the divertor. The evolution of the heat flux footprint at the outer target was studied. Runaway electrons were studied using new unique systems—impact calorimetry, carbon pellet injection technique, wide variety of magnetic perturbations. Radial feedback control was imposed on the beam. Forces during plasma disruptions were monitored by a number of new diagnostics for vacuum vessel (VV) motion in order to contribute to the scaling laws of sideways disruption forces for ITER. Current flows towards the divertor tiles, incl. possible short-circuiting through PFCs, were investigated during the VDE experiments. The results support ATEC model and improve understanding of disruption loads.
In this paper, experimental growth rates are positively compared to numerical predictions for the new geometry of the Experimental Advanced Superconducting Tokamak (EAST) and for a wide variety of plasma equilibrium configurations, hence significantly extending the validation range as compared to previous works. The general result that the CarMa0 code is adequate to reproduce the experimental situation in EAST is confirmed. In addition, we investigate the effects of different assumptions on the plasma response model, on the structures and on plasma boundary.
About Me
Fabio Villone (PhD in Electrical Engineering) works at the University of Naples Federico II, Naples, Italy.
Fabio Villone (PhD in Electrical Engineering) works at the University of Naples Federico II, Naples, Italy.