| Based on the intrinsic magnetic flux pinning characteristics a high temperature superconductor (HTS) exhibits when exposed to a magnetic field, its levitation properties has unique advantages such as self-stability without any control equipment needed and exhibiting no pollution when compared to other conventional electric and magnetic levitation systems. Aside from the application of HTS on a maglev vehicle, it can be employed in many other applications such as HTS flywheels for storing energy, electric motor in the rotary and linear forms, current fault limiters and high field laboratory magnets. A lot of research on HTS maglev vehicle system have been done since the first man-loading HTS maglev test vehicle has been developed successfully in 2000. Now, in the study of superconducting levitation, the experimental researches are more than the theoretical ones, the researches on static or quasi-static characteristics are more than these on dynamic ones and also the levitation performance researches are more than these on guidance performance ones. Especially, because of nonlinear of E-J relation, electromagnetic coupling characteristics and anisotropic property of HTS materials, the theoretical researches on HTS maglev vehicle system are very difficult.For a maglev vehicle system its guidance performance is of vital importance, so it is necessary to study the guidance characteristics of the HTS maglev system both theoretically and experimentally. In this dissertation, for a typical superconducting levitation style which is composed of a bulk superconductor suspended above a permanent magnet guideway (PMG), the guidance characteristics of the system was investigated computationally followed by experimental work. Based on the proposed 3D-modeling numerical solutions of electromagnetic behavior of a HTS bulk sample, grid multiplexing technology which the meshing nodes within the HTS bulk were used to represent the center of pinning to simulate flux pinning of HTS bulk is used. if solution area lies in the interior of the HTS bulk and the meshing nodes is within the HTS bulk, the each meshing node is defined as a pinning center to simulate pinning characteristic of flux, and an applied field value just the position is forced to the node as an initial value which the value is to solute at field cooling position when initial unit stiffness matrix is obtained. That is the fields cooling sense has been done.The resolved code of the 3D-modeling of high temperature Maglev was developed with FORTRAN language. Comparisons between the experimental and numerical results indicated the effectiveness of the method utilized in the thesis.On this basis of analyzings the electromagnetic field of the studied HTSC, monitoring of the guidance force charactericstics of the HTS bulk over a PMG by experiment and 3D simulation was carried out. Firstly, matrix arraies which consist of FH (Field Cooling Height) and WH(Working Height) were established to study numerically the relationship between guidance force and lateral displacement at the same FH the different WH or the same WH the different FH, and the relationship between guideforce hysteresis curves and FH or WH was studied numerically taking into considerations when employing two types of PMG, ones of them being the Halbach PMG. It was found there was a little different when the trend of changes of the guidance characteristics was same seemly at different applied fields, and the change of the guideforce characteristics above the Halbach PMG was more completed than the peak PMG. The relationship of the lateral reversible regions and the FH and WH of the HTS bulk over two types of PMGs were studied experimentally. Results show that the lateral reversible region of the HTS bulk was not only proportional to the magnitude of the guidance force or guideforce hysteresis, but was closely related to the external applied magnetic field structure, FH, WH, and the size and shape of the HTS bulk. A conclusion that the lateral reversible region of HTS bulk over the single peak symmetrical PMG prior to multi-peak Halbach PMG was obtained. Several methods to increase the lateral reversible region are proposed in order to improve the stability of the system.To further investigate existing complications of the guidance characteristics of the HTS maglev system, the time evolution of the levitation and guidance force at different lateral displacements and the influence of approaching speeds on the time evolution of levitation force and guidance force of an HTS bulk above two types of NdFeB guideways were investigated experimentally. The results obtained indicated that the time evolution of the levitation varied faster than the guidance force during the lateral displacement and the approaching speeds had no observable effect on the time evolution of forces.Lastly, on the basis of investigating the complications of the guidance characteristics in this report, the curve route levitation performance of the HTS maglev system was studied computationally with the use of different magnetic fields to simulate the dynamics of the vehicle when it shifts to a new equilibrium position. From the beginning of the simplest line route of HTS bulk, levitation characteristics of HTS bulk which has different curves route were studied, especially, the levitation characteristics of HTS bulk when it passed a quadratic para-curve were discussed detailed. Results show that different curve routes, the dependence of guideforce on route is little, the magnitude of guideforce is depend on FH, but the change of levitation force at different curve route is large. This provides important scientific theories for the numerical simulation of HTS Maglev vehicle.
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