A permanent magnet linear synchronous motor （PMLSM） for a high temperature superconducting （HTS） maglev system has been studied, including the motor structure, control strategy, and analysis techniques. Finite ele...A permanent magnet linear synchronous motor （PMLSM） for a high temperature superconducting （HTS） maglev system has been studied, including the motor structure, control strategy, and analysis techniques. Finite element analysis （FEA） of magnetic field is conducted to accurately calculate major motor parameters. Equivalent electrical circuit is used to predict the drive＇s steady-state characteristics, and a phase variable model is applied to predict the dynamic performance. Preliminary experiment with a prototype has been made to verify the theoretical analysis and the HTS-PM synchronous driving technology.展开更多
In order to improve the overall performance of high temperature superconducting （HTS） motor, a radial connection torque tube with high strength and low thermal leakage has been designed. Firstly, fiberglass epoxy co...In order to improve the overall performance of high temperature superconducting （HTS） motor, a radial connection torque tube with high strength and low thermal leakage has been designed. Firstly, fiberglass epoxy composite is chosen as con- struction material. The structural size of the torque tube is obtained by means of load analysis and theoretical calculation. Secondly, thermal leakage of the torque tube is calculated with both theo- retical method and 3D finite-element analysis （FEA）. According to the result of the thermal analysis and mechanical loads, the struc- tural stresses of the torque tube are also obtained by FEA method. Lastly, a low temperature test platform is developed to verify the strength and the thermal leakage of the torque tube. The results show that the maximal shear stress of the torque tube is 24.3 MPa and thermal leakage of torque tube is 10.5 W, which satisfy the design requirements of the HTS motor. The torque tube also works in good condition at full-power and full-torque testing of the motor. The design method is also applicable for other similar design of torque tube in other applications.展开更多
The development of high temperature superconducting(HTS)tapes has recently made great progress,and Bi-based tapes(1 G) and YBCO coated conductor(2 G)are commercially fabricated with practical length.Application of HTS...The development of high temperature superconducting(HTS)tapes has recently made great progress,and Bi-based tapes(1 G) and YBCO coated conductor(2 G)are commercially fabricated with practical length.Application of HTS in electric power apparatuses made important achievement,various superconducting devices were demonstrated in grid,laying solid foundation for their commercialization.However,since their intrinsic microscopic defects such as weak-link,granularity,small second phase likely exist,critical current and index n value of the HTS tapes in practical length are impossible homogeneous,which have significant influences on safety,stability and efficiency of the HTS apparatuses.Therefore,critical current and index n value are two important parameters describing inhomogeneity of HTS tapes,thus two important indices for evaluating quality of practical long HTS tapes.This paper focuses on main progresses in inhomogeneity of critical current and index n value measurements on HTS tapes using contact-free methods.The statistical analytical methods evaluating the inhomogeneity of critical current and index n value are suggested.They can provide essential references for design and operation of HTS apparatuses.展开更多
文摘A permanent magnet linear synchronous motor （PMLSM） for a high temperature superconducting （HTS） maglev system has been studied, including the motor structure, control strategy, and analysis techniques. Finite element analysis （FEA） of magnetic field is conducted to accurately calculate major motor parameters. Equivalent electrical circuit is used to predict the drive＇s steady-state characteristics, and a phase variable model is applied to predict the dynamic performance. Preliminary experiment with a prototype has been made to verify the theoretical analysis and the HTS-PM synchronous driving technology.
基金Supported by the High Technology Research and Development Program of China(863 Program)(2008AA030601)
文摘In order to improve the overall performance of high temperature superconducting （HTS） motor, a radial connection torque tube with high strength and low thermal leakage has been designed. Firstly, fiberglass epoxy composite is chosen as con- struction material. The structural size of the torque tube is obtained by means of load analysis and theoretical calculation. Secondly, thermal leakage of the torque tube is calculated with both theo- retical method and 3D finite-element analysis （FEA）. According to the result of the thermal analysis and mechanical loads, the struc- tural stresses of the torque tube are also obtained by FEA method. Lastly, a low temperature test platform is developed to verify the strength and the thermal leakage of the torque tube. The results show that the maximal shear stress of the torque tube is 24.3 MPa and thermal leakage of torque tube is 10.5 W, which satisfy the design requirements of the HTS motor. The torque tube also works in good condition at full-power and full-torque testing of the motor. The design method is also applicable for other similar design of torque tube in other applications.
基金supported by the Specialized Research Fund for the Doc-toral Program of Higher Education(Grant No.D00033)the Foundation of North China Electric Power University(Grant No.KH0194)
文摘The development of high temperature superconducting(HTS)tapes has recently made great progress,and Bi-based tapes(1 G) and YBCO coated conductor(2 G)are commercially fabricated with practical length.Application of HTS in electric power apparatuses made important achievement,various superconducting devices were demonstrated in grid,laying solid foundation for their commercialization.However,since their intrinsic microscopic defects such as weak-link,granularity,small second phase likely exist,critical current and index n value of the HTS tapes in practical length are impossible homogeneous,which have significant influences on safety,stability and efficiency of the HTS apparatuses.Therefore,critical current and index n value are two important parameters describing inhomogeneity of HTS tapes,thus two important indices for evaluating quality of practical long HTS tapes.This paper focuses on main progresses in inhomogeneity of critical current and index n value measurements on HTS tapes using contact-free methods.The statistical analytical methods evaluating the inhomogeneity of critical current and index n value are suggested.They can provide essential references for design and operation of HTS apparatuses.
