NbTi foil thermally controlled switches for superconducting converters with operation frequency up to 50 Hz. Part 1: Experiment

The increase of the operation frequency of superconducting converters up to 50 Hz opens new ways to improve their parameters. Thermally controlled switches using NbTi foil are able to operate at industrial frequency with reasonable efficiency and dynamic parameters. Such switches have been developed and tested. The paper presents experimental results of static and dynamic behavior of the switches. The rectification mode was tested with different shapes of the applied voltage, with currents from 150 to 450 A, voltages from 10 mV to 2.5 V and recovery times between 1 and 10 ms. The switches presented here have experimentally demonstrated superior dynamic parameters at higher efficiency than the ones reported in literature up to now

Development of a 50-60 Hz thermally switched superconducting rectifier

A full-wave thermally switched superconducting rectifier, able to operate directly from the mains at the 50-60-Hz frequency, has been developed. Typical design output values of this device are a current of 300 A, a voltage of up to 1 V, an average power of up to 100 VA, and an efficiency better than 95%. The rectification is achieved by means of fast-response switches and an iron core transformer. A simple and reliable algorithm for the rectifier operation, based on the measured current change across the switches, was developed and tested while powering a small magnet. The new features of the rectifier allow for a simplification of the construction and a significant reduction of cost, mass, and volum

Simulation of complex electric circuits with superconducting elements

Effective computer simulation of transient and stationary processes in different power circuits with superconducting elements (SE) becomes possible due to creation of a set of user's models and available commercial analog simulation systems such as SPICE, NAP or the like with a standard set of electrotechnical elements in the library. The suggested method of simulation as compared to analytical ones is less inertial. Comparison of calculated and experimental data shows their good correspondence even in complex cases when n - s boundary in SE moves with positive or negative acceleration