HTS-SQUIDs im Kraftwerk: Verringerung der Stoerfeldempfindlichkeit des SQUID-Systems Abschlussbericht

Abstract

The aim of the project was the development of a measurement system, based on SQUIDs (Superconducting Quantum Interference Detector) using high-temperature superconductors, which is usable for NDE (non-destructive evaluation) in industrial environment. To realize this task, both - new SQUID gradiometers and a new SQUID electronics - have been developed. The susceptibility of the SQUID structures to flux penetration by large environmental magnetic fields could be minimized by technology and layout development as well. Using a combination of gradiometer SQUID and magnetometer SQUID new sensors were developed, which are highly balanced, sensitive against magnetic field gradients and, at the same time, resistant against disturbances and movements within the Earth's field. The new SQUID electronics allows the use of bias current reversal with frequencies in the MHz range. Therewith a low-noise operation is possible also at low frequencies obtaining large bandwidth and dynamic range at the same time. The electronics has been integrated, thus allowing a robust operation. The power of the complete SQUID system could be shown exemplary with an NDE, where the SQUID was moved by hand across the workpiece in the disturbed environment of the lab. (orig.)SIGLEAvailable from TIB Hannover: F04B607 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman