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Multiseeded YBaCuO bulk crystallized by melt growth process is usually employed as the levitated magnet in high-temperature superconducting (HTS) maglev system. However, to the state of art, the intergrain supercurrent between different domains in the multiseeded bulk superconductor is much harder to simulate than the intragrain supercurrent in the single-seeded bulk, hindering the numerical study of multiseeded bulks. In this paper, we first discussed how to simulate the electromagnetic response of multiseeded bulk superconductor levitated above permanent magnetic guideway (PMG) through treating the multiseeded bulk as magnetically coupling but electric uncoupling domains, discriminating from assuming it as a single-seeded bulk superconductor. This model was validated through experiments of a three-seeded bulk levitated at different positions above a Halbach-derived PMG, comparing with a single-seeded bulk with the same geometrical dimensions. To realize a heavy-load HTS maglev system that can carry over a ton per meter length of levitation constituent, we introduced the feasible paths to increase the load, increasing the volumes of superconductors and PMs. We also optimized the selective configurations of the HTS maglev system by the genetic algorithm to reduce the total cost. The final summarized rules for designing the heavy-load HTS maglev system applied multiseeded bulk superconductors and Halbach-derived PMGs are deemed important to industrial-level application. [ABSTRACT FROM AUTHOR]

In this paper, the 3-D model proposed in Part I of this study is verified in detail on the basis of a levitation/suspension system composed of a rectangular single-domain Y-Ba-Cu-O and a cylindrical Nd-Fe-B magnet or a permanent magnet guideway (PMG) assembled by the Nd-Fe-B magnets. The magnetic forces along the vertical direction perpendicular or the transverse direction parallel to the surface of the PMG(or magnet) were calculated and compared well with the measured data under vertical and transverse displacements. The computed results of the induced current distribution within the Y-Ba-Cu-O domain, as well as the magnetic field profiles in the Y-Ba-Cu-O and its vicinal region, were also presented and discussed. [ABSTRACT FROM AUTHOR]

A magnetic levitation technique with high-Tc superconductor (HTS) has received significant interest for a wide range of applications after its discovery due to its unique inherent stability, which gives a fundamental significance to evaluate the HTS magnetic levitation in both experiment and calculation. To numerically investigate the HTS magnetic levitation, a 3-D model describing the electromagnetic property of the HTS, including its anisotropic behavior, was established by incorporating the current vector potential and Helmholtz's theorem. In addition to the commonly considered nonlinear E--J characteristic in the reported calculation, we introduce an elliptical model to formulate the angular dependence of the critical current density Jc resulting from the anisotropic behavior of the HTS. To numerically resolve the governing equations of the 3-D model, Galerkin's finite-element method and the Crank--Nicolson-θ method were employed to discretize the governing equations in space and time domains, respectively. The obtained algebraic equations were firstly linearized by the Newton--Raphson method, and then an extended format of the incomplete Cholesky-conjugate gradient method was applied to solve the linear algebraic equations. The 3-D model was implemented by a self-written numerical program based on a VC++ platform to calculate the magnetic force of a bulk HTS exposed to applied field generated by a permanent magnet guideway (PMG) assembled by the Nd-F-e-B magnets. In this paper, we present the numerical results of the levitation force of a moving bulk HTS above the PMG with different mesh densities and number of time steps. This presents a preliminary validation of the 3-D model proposed in this paper. [ABSTRACT FROM AUTHOR]