Characterization of the Quench Dection System for ITER _ Final Report 1995

The purpose of this study is to assess the expected response of conventional and non-conventional quench detection sensors proposed for the ITER coils, and to be tested in the QUELL experiment in SULTAN. The assessment is based on simulation of thermo-hydraulic transients in the ITER coils for various operating conditions, and a tentative definition of the transfer functions of each sensor concept. It is shown that, for the investigated conditions, the co-wound voltage tap is more accurate than other sensors investigated, i.e. the optical fiber, the Super High Frequency method, sensors based on hydraulic properties and conventional voltage balance method. The additional complication associated with the insertion of taps in the conductor is well offset by the low sensitivity to external disturbances.