Abstract
Large electric superconducting machines are being sought to solve emissions challenges in aircraft and provide a solution to >12 MW wind turbine electricity generation. Superconducting motors with only high temperature superconducting (HTS) armatures can offer advantages of high reliability, high power density, and high efficiency compared with conventional superconducting motors. In this paper, a novel HTS squirrel-cage induction motor is proposed for high speed operation, which adopts the structure of HTS windings with a certain inclination angle in the stator slots. Due to the limitation of curvature radius of superconducting tapes, the pitch of HTS windings can be only set to 1 and adopt the short pitch arrangement structure, which such design details of the HTS motor would ensure the superconducting coils can undertake larger current and reduce AC losses. In order to keep the HTS windings in superconducting state and larger current density, a special fixed cryogenic cooling system below 70 K with the method of gas extraction and decompression, which is made of aramid fiber, has been fabricated and the whole structure of the stator is placed in liquid nitrogen. According to the motor control principles and electromagnetic field theory, the electrical performances of the novel designed stator-HTS motor, which driven by the variable-voltage variable-frequency (VVVF) inverter, are analyzed including the flux density distributions, the torque, the induced electromotive force, losses and efficiency by using the finite element method. Finally, the components of HTS squirrel-cage induction motor have been manufactured according to the designed parameters. Next step, the motor will be assembled and tested.
Highlights
The continuous improvement of the properties of high temperature superconducting materials creates more opportunities for high power superconducting motors [1]
Compared with the conventional machines of same power, high temperature superconducting (HTS) motors have the advantages of small volume, light weight, high power density and being less expensive to operate because of their high current density, ironless design, high magnetic field, and high operating temperature [2,3,4,5,6,7]
We have focused on the HTS induction motor [19,20,21,22], in which the superconducting material is only applied to the stator part
Summary
The continuous improvement of the properties of high temperature superconducting materials creates more opportunities for high power superconducting motors [1]. Most superconducting machines adopt superconducting material as the rotor poles for the field to supply high air-gap magnetic flux density, the HTS motor has high power density and has been studied by many researchers and institutions, but this structure brings some problems such as cooling, maintenance, mechanical speed and manufacture cost, etc., and this technology is complex [15,16,17,18]. Because the superconducting magnets face an air gap with a high flux density at all times, the magnetic flux density in the superconducting coils is high This will affect the critical current of the superconducting tapes, so the operation temperature of superconducting magnets must decrease to 20–30 K to eliminate this influence. According to the design parameters, the components of HTS squirrel-cage induction motor have been manufactured and the motor will be assembled and tested in the stage
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
