Comparison of two different techniques for long term magnetic measurements in nuclear fusion research

The continuous measurement of magnetic fields for long time intervals is an important issue in nuclear fusion research. High temperatures and neutron fluxes limit to inductive sensors the conventional measurement systems suitable for this application, thus requiring the use of active integrators. In the paper a new approach based on a hybrid electromechanical sensor is compared with a conventional circuit, in order to investigate advantages and drawbacks of both the systems. A series of tests have been carried out on the two sensors, to evaluate the precision attainable. A discussion on sources of error is carried out, to highlight the limits of the conventional approach and the conditions in which the hybrid sensor offers better performance