Low-complexity voltage and current sources for large-scale quench detection of high-temperature superconducting cables

In this work, the design of precision voltage and current sources for a new quench detection system for the protection of superconducting power cables is proposed. The key strength of the design resides in its low complexity, which allows to obtain a low-cost and reliable hardware implementation for the new detector. The voltage source output goes from 200 mV to 800 mV, while the current source output is adjustable between 50 mA and 1 A. Experimental results from the sources characterization campaign validate the design: 24-hours time stability is demonstrated to be about 20 ppm for the voltage source, and below 1000 ppm for the minimum current of 50 mA of the current source. Furthermore, the measured superposed noise is less than -80 dBV and the Mean Time Between Failures (MTBF) is estimated to be about 20 million hours for both sources. The improvement of the quench detector features is also demonstrated through further experiments. The obtained results demonstrate the effectiveness of the proposed detection mechanism and pave the way for further research on large-scale use of high-temperature superconducting cables.