The application of parametric 3D finite element modelling techniques to evaluate the performance of a magnetic sensor system.

This paper describes the application of parametric three-dimensional (3D) finite element analysis techniques to accurately model the response of a new industrial electromagnetic sensing system. The study focuses on a magnetic transformation detector for hot steel strip, which is capable of measuring the austenite-to-ferrite phase transformation fraction of hot steel on-line as the material cools below the Curie temperature. This sensor presents several challenges with regard to modelling its response. First, small changes (0.3 mT) in the measured magnetic field must be detected against a much larger background value (160 mT). Second, the response of the sensor to variation in lift-off must be accurately determined so that changes in lift-off could be subsequently rejected using an appropriate compensation algorithm. Finally, an accurate model (error