Electromagnetic Analysis Of High Temperature Superconductor Linear Induction Motor

Linear induction motor (LIM) is widely used in the industrial fields for its simple, firm structure and linear motion feature without the translation mechanism. With the development of LIM application, LIM has promising future in the urban rail-bound transit systems. Besides, great progress has made in the technology of superconductivity recently, the fabrication process and property of Bi superconducting strips are improved greatly. It is possible to combine the LIM technology with superconductivity technology. The thesis designed a new type of high temperature superconductor linear induction motor (HTS LIM). The electromagnetic properties of the motor were analyzed.Firstly, the thesis introduced the current state of LIM using in rail-bound transit systems. The feasibility of LIM with superconductivity technology was illustrated in the thesis. The structural parameters which considered the design requirements of HTS LIM was given by the design formula of conventional LIM with copper tape winding. The fabrication process of superconducting coils winding and HTS LIM were presented.Secondly, the motor model was analyzed by 2D transient finite element method (FEM) to get the electromagnetic properties of HTSLIM. The maximum vertical magnetic field on the surface of superconducting strips caused by slot Leakage flux was analyzed, too. The maximum current of HTS LIM was obtained by contrasting the relation curve of vertical magnetic field and critical current at 77K. An experimental investigation was carried out on both copper tape winding prototype motor and HTS one. Electrical parameters were deduced from these tests and also compared with the analysis results from FEM.Lastly, an optimizing design scheme was proposed for the energy-saving model of HTS LIM. By researching the influence of slot width, slot high, tooth width, yoke high and special secondary on the properties of HTS LIM, a new model which separated the dewar from the iron core were abtained in the thesis. FEM analysis about the model was presented, too.