Computational And Experimental Studies On The Electromagnetic Properties Of Superconducting Linear Driving Motor

With the development of motor theory, control method and material performance, as well as the improvement of manufacturing capacity for high performance components, linear motor has received a rapid development. In recent years, the advantages of linear motor are more prominent over rotary motor with the pressing need of high thrust density, high precision and high speed linear driving system, which makes it an overarching concern for researchers in motor. At the same time, the development of superconducting material refreshes quickly, which inspires a new research wave of high temperature superconducting linear synchronous motor (HTS LSM). There are some defects in PM LSM, such as small fields and adsorption of ferromagnetic material. To solve these problems, this paper designed a HTS LSM with four superconducting coils as its secondary.To study the feasibility and superiority of the HTS LSM with four superconducting coils as secondary, this paper built an equation based on the HTS constitutive relationship between E and J to consider the strongly non-linearity of HTS resistance. Besides, to solve the problems caused by traditional power supply mode, the simulation model and experimental devices of wireless power supply system were constructed.As to the HTS LSM simulation analysis, this paper studied it’s performance parameter, such as the field distribution, relationship between thrust and height of air gap, the maximum load capacity and start frequency on the premise that the motor can start directly. The variable frequency start of HTS LSM was also studied.Concerning the feasibility of finite element analysis method, supportive experiment was designed and related comparison was made between experimental result and simulation result, for example, the relationship between thrust and height of air gap. Besides, the validity of constant acceleration start based on constant ratio of voltage and frequency was also confirmed by this experiment.For wireless power transfer system, the field distribution and received voltage of linear array structure was analyzed based on finite element software COMSOL, whose authority was tested by relevant experiment. This research showed that when the antenna coils were placed as a linear array with an appropriate separation distance, the received voltage could keep stable in the quasistatic process.