Progress in the Design and Testing of In-Vessel Magnetic Pickup Coils for ITER

This paper presents the results of the RD activities recently performed to achieve the preliminary design of electromagnetic transducers for in-vessel local magnetic field measurements at low frequency (<30 kHz) for ITER. The study is based on thermoelectrical and electromagnetic bench tests performed on a batch of 40 sensor prototypes manufactured with the low temperature cofired ceramic (LTCC) technology. Also, the outcomes of a first neutron irradiation test on LTCC sensors are presented. The development of an alternative concept of a magnetic sensor for ITER, based on mineral insulated cables winding is also reported, with suitable thermomechanical and electromagnetic numerical analyses performed to assess the reliability of such sensors within the ITER operating conditions.