Magnetization reduction by varying normal field in stacks of composite superconductors in an electrical motor

Trapped field magnets of superconducting stacks could be an alternative to conventional magnets in electrical machine applications. A conceptual design of an electrical motor using these stacks was proposed in [1,2]. Superconducting stacks offer many advantages; however, they can be demagnetized when exposed to the varying field present in electrical motors during operation. This varying field can be generated by salient magnetic circuit or generated from the armature winding as harmonics. To study this demagnetization effect, we carried out an experiment on a superconducting stack in an electrical machine, exposing it to different levels of varying cross and normal fields. The experimental measurements recorded a demagnetization of the stack. In this work, the analyses of the reduction of magnetization of the superconducting stack by an alternating normal field and the comparison of the results with experimental measurements in the electrical motor are presented.

MEASURING INSTALLATION FOR DETERMINING CURRENT-VOLTAGE CHARACTERISTICS OF COMPOSITE SUPERCONDUCTORS IN THE PRODUCTION OF CRYOGENIC TECHNIQUE

The method and measuring installation for determining the actual critical current values in superconductors, at helium temperatures, coming to the market from domestic and foreign manufacturers of composite wire, round or rectangular section, based on the Nb-Ti alloy, are considered.