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This study tries to observe the aerodynamics of a moving coil linear motor (MCLM) under the conditions of high frequency and high speed, a three-dimension aerodynamics analysis and experimental investigation of the designed MCLM provided with different thrust coil bobbins (TCBs) based on dynamic meshes technique using computational fluid dynamics (CFD) are proposed. Results show that with the increase of moving frequency and speed, the air damping of TCB subassembly is nearly proportional to the square of the speed. Punching a number of holes on the end face of the TCB could greatly improve the air flow capacity and enhance the distribution of pressure and velocity of the flow field around. Compared with proposal 1, the air damping of proposal 2 and proposal 3 is decreased by 64.3% and 97.1%, respectively. Simulation results show that the response time and frequency of the designed MCLM with proposal 3 is better than those with proposal 1 and proposal 2. In addition, the experimental frequency and response time of the designed MCLM with proposal 3 are 300Hz at 3dB and 4ms, respectively. As evident in this study, analysis and experimental results show that the air damping can be decreased by the structural optimization of the MCLM, and the designed MCLM with proposal 3 can realize good performance of high frequency and rapid response. [ABSTRACT FROM AUTHOR]

The force-speed relationship of a bulk YBCOmoving above a permanent magnetic guideway was studied. The experiments show that the levitation forces at the lowest position Fmax increase with the increment of descending speed and tend to approach a certain levitation force FS. max. Calculations based on a simplified superconducting ring and flux flow model show that the force variations can be ascribed to the resistive electric field produced by flux motion. Further calculation reveals that, by increasing the descending speed, the thermo-dissipation inside the superconducting ring immediately after the descending process exponentially declines, approaching zero while the speed approaches infinity, and Fmax reaches FS. max. Therefore, the thermo-dissipation inside the bulk YBCO can be defined as a parameter for evaluating levitation force losses. Those results might be useful in pragmatic design of high-Tc superconducting levitation devices and magnetization of type-II superconductors. [ABSTRACT FROM AUTHOR]

The high-Tc superconductive (HTS) hybrid Maglev with the auxiliary permanent magnet (PM) is a useful method to improve the system load density and stiffness. The auxiliary PM changes the magnetic circuits and increases the instability of the Maglev system. To investigate the levitation performance, different HTS hybrid Maglev arrangements involving PM and bulk HTS were tested above the permanent magnet guideway. Some useful conclusions and reference for relative design can be found from the experimental results and analyses. [ABSTRACT FROM AUTHOR]

High temperature superconducting (HTS) bulk sample acts as quasi-permanent magnet when it traps magnetic field, and the superconducting bulk magnet can substitute the traditional permanent magnet in the engineering of the linear motor for the purpose of achieving higher efficiency. The electromagnetic forces between the HTS bulk magnets and the ac magnetic field are the most important parameters to consider for the engineering of a motor. We measured the static vertical and thrust forces of an HTS magnet subject to a sinusoidal traveling magnetic field at different trapped fields and at different current amplitude and frequencies. The force relaxation of the HTS bulk magnet was also compared with that of a traditional permanent magnet. The feasibility of replacing the conventional magnet in the ac application machines by HTS bulk ones was preliminary validated experimentally. [ABSTRACT FROM AUTHOR]

A novel high-temperature superconducting (HTS) magnetic helix transmission mechanism is introduced to overcome the inevitable friction and wear of a traditional mechanical helix transmission mechanism. It is based on the principle that a high-temperature superconductor can move in one direction with a uniform magnetic field without any resistance. The mechanical property of this mechanism is theoretically studied. Results show that the driving torque and axial carrying capacity are closely dependent on the lead angle of the magnetic bolt. [ABSTRACT FROM AUTHOR]

A high-temperature superconducting (HTS) magnetic transmission device is introduced. The key part of the transmission device is an HTS magnetic helix transmission mechanism, which consists of a magnetic bolt and an HTS nut, and its strong points are being frictionless and having high efficiency. The transport platform is driven along the direction of the magnetic bolt. All moving parts of the device do not come into contact with the load that is transported by the transport platform. The basic mechanical properties of this device are studied. The position precision and angle precision of the transport platform are discussed. [ABSTRACT FROM AUTHOR]