| With the unique characteristic of self-stable levitation, High Temperature Superconducting (HTS) levitation system has caused worldwide concern, and many organizations engage in its research. HTS Maglev vehicle, represented by Century which is the first man-load one, is based on this novel self-stable levitation. HTS Maglev vehicle is energy conservation, environmental, safe, high speed and comfortable, so that it would be an important choice for the high and new technology of rail transit in our way to sustainable development.Equilibrating the gravity field of the Earth is a fundamental premise for HTS Maglev vehicle system design and application. By contrast, the dynamic stability of the system in running condition would be much more crucial, which includes the dynamic load capacity (motional levitation force and guidance force) and dynamic parameters (resonance frequency, dynamic stiffness and damping coefficient). Therefore, the thesis considered the operating dynamic characteristics of the HTS Maglev vehicle system as below.The hammer produced occasional perturbations; then vibrational measurements of multiple arranging bulks arrays over a new Halbach type Permanent Magnet Guideway (PMG) were made to discuss the free response. The experimental results show:horizontal dynamic stiffness is not apparently affected by the location of the bulk; vertical dynamic stiffness is bigger when all the bulks located in potential-well field area; damping coefficient is nonlinear with Field-Cooling-Height (FCH) and horizontal damping coefficient is bigger while FCH is lower than 15 mm.Eddy current damper in multiple thicknesses had been applied in the vibrational measurements for the interest of the damping improvement. We discussed the free response of the bulk arrays located both in potential-well field area and magnetic field peak area with eddy current damper. We also took the quasi-static levitation characteristic into consideration and finally found a recommended thickness of eddy current damper applied in HTS Maglev vehicle system.In HTS Maglev dynamic measurement system (SCML-03), by the means of operation mode setting and PMG rotating speed controlling, the levitation force oscillation and attenuation due to magnetic field inhomogeneous of PMG were investigated under the different relative motion state, which mainly include:different field history from cooling to working, magnetic field inhomogeneous caused by cooling location, acceleration and then deceleration repeatedly, accelerating step by step and then decelerating step by step, the different working height (WH) or FCH and etc. It was found that the levitation force tends to attenuate less in faster running in the speed range between 0 and 238 km/h which is the experimental velocity record at present, which reflected that the shielding current internal of bulk would decay less in higher velocity. The different field history from cooling to working would not affect the levitation force saturating value although their tendency is a little different. The levitation force attenuating occurred mainly in early period and saturated faster in higher velocity, which would be benefit for long-term operation of the HTS Maglev system.Finally, the levitation force oscillating characteristic with different FCH and WH was investigated and we compared the dynamic stability of the levitation force and suspension force. It was found that the suspension force decay dramatically, which would indicate relatively bad load capacity compare to levitation force.The main innovation of this thesis is that the dynamic parameters of four bulk arrays on new Halbach PMG are compared and several complicated field history situation has been considered by varying PMG rotating mode and changing cooling condition.The conclusions provided scientific basis for the dynamic stability of HTS Maglev vehicle system, and would help for further investigation on HTS Maglev vehicle experimental line.
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