Preliminary studies for the conceptual design of the quench detection system for the DTT TF superconducting magnets

摘要

The superconducting DTT magnetic system needs a quench detection systems (QDSs) fast enough to trigger the dumping of the magnetic energy in case of quench and avoid irreversible damage of the cable systems. With this aim, a primary system based on the detection of the resistive voltage associated with the quench offers the best quench detection guarantees. The tokamak environment is affected by several electromagnetic noises during plasma scenarios so that the resistive voltage detection, during normal operation, can be compromised by the presence of large voltages induced by self and mutual magnetic coupling among coils and with plasma or passive elements: the resulting inductive voltages across a TF coil, or part thereof, could be much higher than the quench voltage thresholds. Voltage compensations techniques, therefore, have necessarily to be foreseen in the QDSs conceptual design, to discriminate the resistive component associated with the quench. We present a reconnaissance of all known electromagnetic noises that could affect a TF coils QDS in DTT: this analysis is conducted by means of analytical calculations, made up with the aim to evaluate and have a prevision of the maximum extent of the voltages induced across TF coils and Double Pancakes (DPs) during, in particular, the Single Null (SN) scenario.