Electromechanical Analysis of HTS Cage Rotors for Induction-Synchronous Machines

A recent promising solution to expand the current limits of electrical machines is using High-Temperature Superconductor (HTS) tapes in the rotor of induction-synchronous machines (HTS-ISM). These machines present the co-existence of synchronous and slip modes due to the resistive and superconducting behaviors of HTS tapes. To evaluate the electromechanical performance of HTS tapes in this type of machine, a magnetic circuit prototype was made to mirror the operating conditions of the HTS-ISM. First, AC loss measurements were carried out with 1G BSCCO and 2G YBCO tapes in an air-core LN
₂
environment, and obtained experimental results were used to calibrate each tape E-J power law. Once characterized and validated, the HTS-calibrated model was used to study the HTS-ISM machine via Finite Element Modelling and Analysis. In this paper, special focus is given to the machine's start-up conditions. These were replicated using the magnetic circuit prototype, where AC losses have been evaluated for different tape configurations.